[trader_4]

On Sunday, August 5, 2018 at 11:41:25 AM UTC-4, Arlen Holder wrote:
On 5 Aug 2018 07:31:19 GMT, Xeno wrote:

It always amazes me the dependence people place on those codes without
really understanding the *system* that is generating the codes and, in
most cases, the *limitations* of those systems.

I agree with both you and Scott that *most people* (not me, but most
people), when they see a sensor code, they replace the sensor.

It could be a temperature sensor for heaven's sake, and they replace the
sensor.

As I told Scott, I'm an EE so I know how to test a sensor, but in the case
of oxygen sensors, I've had five years' experience with the toyota and
bimmer where a bad sensor will make the FTP not set the related monitors
for hundreds of miles. IN the case of the toyota, it took about 400 miles,
and it took more than a thousand in the case of the bimmer.

In *both* cases, I took it to the smog referee and passed with flying
colors, even with the registers unset (since that's what the BAR smog
referee did in years past). They don't do that anymore, so you're stuck
now.

I know the FTP inside and out, and spoke to the BAR engineers who know it
even better than I do. I went over all the dozen conditions that an engine
must be in order for a monitor to be set.

Remember, in both cases, the bar smog referee PASSED the vehicle.

The problem is much more sinister than you seem to have experience with.
But I do agree with you that *most people* just throw parts at a problem.

What I find hilarious is what happens AFTER people throw parts at a
problem. Let's take the two corner cases, assuming, for example, that a
problem can have FIVE (for argument's sake) caususes:

1. If they guess right on the first pass, they claim that they are an utter
genius, and after that, for the rest of their lives, anyone who has that
same problem, they swear the answer is that first solution.
2. If they guess wrong, and have to replace all five parts, they swear that
the first four parts were bad, until they finally get to the right part.

Anyway, the main point here is that we all agree that throwing parts at a
problem is a crazy way to "fix things" but you have to admit a lot of car
problems are fixed that way.


It may not be that crazy if you're paying $120 an hour for diagnosis.
It could be totally logical to replace two $30 parts, instead of
spending an hour figuring out which one it is. If you're doing it
yourself and the labor is free, then it changes the equation.

[rbowman]

On 08/05/2018 01:01 AM, Arlen Holder wrote:
(Of course, the containers themselves are CARB/EPA approved so, as you're
well aware, the gas goes in and doesn't come out easily - due to the ****ty
spouts - but that's a different beast altogether which I've solved
separately by not using them).

'Repair kits' are popular around here and include a free flowing spout
and vent. Of course, they should only be used to repair older containers.

The asshole who mandated those spouts should spend eternity filling a
lawnmower with a full 5 gallon jug equipped with the monstrosity.

[Clare Snyder]

On Sun, 5 Aug 2018 07:01:48 -0000 (UTC), Arlen Holder
wrote:

On 4 Aug 2018 20:02:46 GMT, Clare Snyder wrote:

Does your insurance company know?
Long ago I checked with the local fire marshall, who told me that they're
perfectly legal as long as they're in legal containers.

I also checked with the CHP 800 number who said transport of gasoline is
perfectly legal as long as it's less than 600 pounds, which is the federal
limit on "hazardous materials" transport. (It's a felony to transport more
than 600 pounds at a time, but that's more gas than a car can carry.)

I checked with CARB who said that emissions standards don't play a role
unless any one container is over 50 gallons (that's why drums, they told
me, are technically 50 gallons but actually less) and the sum total is less
than 300 gallons.

I checked with OSHA who "recommended" a spill pan, and aired enclosure, but
who said OSHA rules don't apply to homeowners.

There are zero "zoning" rules according to the local planning department
(other than structures must be 100 feet from the road or they need a
permit, but that applies to any structure that is less than 10 by 10 (as I
recall) and 12 feet high (as I recall).

How much fuel do you keep around?

Only about 50 gallons at a time, all in legal containers.

The fire department comes by once a year, unannounced, to write up
fire-break violations - and they "see" the gasoline since it's stored in
big red jugs right out in the open. They don't even blink (and yet, they
make me clear all flammable growth 100 feet from the house and 10 feet from
the propane tanks).

In California, you can't legally fill more than 6 gallon containers at a
gas station, which is a rule that went into effect only relatively
recently, where some of my containers (the WWII style ones) are 6 gallons.

Delivery of gasoline less than 200 to 300 gallons is problematic, where my
ultimate "station" will be in 40-gallon epoxy-lined drums with an electric
pump just like the gas-station pumps. (I have plenty of room for it.)

There are very real safety issues to address - as well as hydrocarbon
emission issues.

I don't do things lightly - I plan them out - as you know. It's no less
safe than you storing a single 5-gallon can of gasoline - the only
difference being the amount - but my 50 gallons is exactly as safe as your
5 gallons. Exactly. The safety is the same. It's only the amount that is
different.

Of course, gasoline is flammable, and of course there are hydrocarbons, but
I am a thorough person, who checked with all the relevant authorities. I
leak as many hydrocarbons as you do when you fill your lawn mower (in fact,
I'm VERY WELL AWARE of hydrocarbons, so I might even leak less than you do
since my process takes them into account somewhat).

If the gas is stored in approved containers, you can keep hundreds of
gallons legally at home. You can fill every inch of your front lawn for
example. As long as each container is legal, there is no limit on numbers
of containers (if they're 5-gallon jugs).

Different rules than here in Ontario.
Up here the insurance companies would not be happy.


The Technical Standards and Safety Authority (TSSA) is responsible for
setting and enforcing the rules governing the storage of petroleum
products. For diesel and gasoline, the Liquid Fuels Handling Code
(LFHC) sets specific rules for different fuel storage facilities; gas
stations, bulk plants and private fuel outlets. Private fuel outlets
are places where petroleum products are dispensed into vehicles,
watercraft or portable containers and are owned or used by the owner
of the private fuel outlet. A private fuel outlet includes farms.

Requirements for Aboveground Farm Fuel Storage Tanks (diesel or
gasoline):

REGISTRATION – There is no requirement to register farm tanks.
However, tanks and associated equipment (pumps, hoses and supports)
must be installed by a certified Petroleum Mechanic in accordance with
the LFHC.

ACCEPTABLE TANKS – Only tanks certified by Underwriters’ Laboratories
of Canada (ULC) may be used. Approved tanks must display a ULC
sticker.

TANK LOCATION – Aboveground farm fuel storage tanks must be located in
accordance with Part IV of the Ontario Fire Code;

Diesel fuel tanks (Class II product) up to 50,000 litres (10,650
gallons) must be located at least 1.5 metres (5') from a building on
the same property and at least 3 metres (10') from the property line.
Diesel fuel tanks (Class II product) up to 2,500 litres (532.5
gallons) may be located zero metres from a building on the same
property and at least 3 metres (10') from the property line.
Gasoline tanks (Class I product) up to 250,000 litres (53,250
gallons) must be located 3 metres (10') from a building on the same
property and at least 3 metres (10') from the property line.

Aboveground farm fuel storage tanks must also be placed a safe
distance from water wells and water courses. Farm fuel storage tanks
must be no less than 15 metres (50') from a drilled well, or no less
than 30 metres (100') from a dug well or water course. Tanks must be
clearly marked (CLEAR DIESEL, COLOURED DIESEL or GASOLINE) to indicate
the product contained.

For underground farm fuel storage tanks, refer to Section 2, LFHC,
2007.

DISPENSING EQUIPMENT – The pump must be located according to ALL of
these specifications;

at least 3 metres (10') from a property line,
at least 3 metres (10') from a highway, as defined in the
Highway Traffic Act,
at least 4.5 metres (14’9?) from any opening in a
building,
at least 1 metre (3’3?) from any building, AND
all electrical hookups must comply with the Ontario
Electrical Safety Code.

DIKING & SECONDARY CONTAINMENT– Aboveground tanks are exempt from
diking and secondary containment if they have a maximum capacity of
5,000 litres (1065 gallons) and any loss or escape of product will
not;

create a hazard to public health or safety,
contaminate any fresh water source or waterway,
interfere with the rights of any person, or
enter into a sewer system, underground stream or drainage
system.

Tanks without a dike must be equipped with an approved overfill
protection and spill containment.

Double wall tanks [maximum capacity of 80,000 litres (18,480 gallons)]
are equivalent to diking.

TANK PROTECTION – Aboveground tanks must be protected from vehicle
collisions. Posts, also known as bollards, provide one option. The
Propane Storage and Handling Code contains these specifications for
bollards;

spaced not more than 54? (1350 mm) apart,
buried not less than 36? (900 mm) below grade,
extend at least 30? (750 mm) above grade,
consist of: a 4? (100 mm) capped steel pipe, a 4? (100 mm)
tube filled with concrete, an 8? (200 mm) square or round
pressure-treated wood post, or a 6? (150 mm) minimum dimension
reinforced concrete post, AND
spaced at least 3½ ft. (1 m) out from the storage tank.

ADDITIONAL REQUIREMENTS – Private fuel outlets also require at least
two (2) fire extinguishers (rated 20-BC) that are readily accessible,
AND the following signs;

NO SMOKING – TURN IGNITION OFF, and
APPROVED PORTABLE CONTAINERS

LIQUID FUELS HANDLING CODE – the code is available from CSA for $120
plus tax and shipping;



Other regulations cover the storage of quantities of flamable
materials in smaller containers.


The big question I have is WHY would you fuel your "road vehicles" at
home if you have to buy it at a regular gas station and transport it
home, - unless you live a LONG ways from the fuel station?


I keep fuel on hand for the lawn mower and snow blower (no more than
15 gallons) and generator - but my "reserve fuel" for the generator is
2 20 lb Propane tanks (it also runs off the domestic natural gas
supply)
There are no rules for how you get the gasoline OUT of the container with
respect to emissions either. But I'm very good about that too.



(Of course, the containers themselves are CARB/EPA approved so, as you're
well aware, the gas goes in and doesn't come out easily - due to the ****ty
spouts - but that's a different beast altogether which I've solved
separately by not using them).

Sure, gas is flammable. But so is the gasoline stored at everyone elses'
house too. They just don't have as much of it. Most people with three cars
in the garage have as much as I have for example, outside.

2. Habitually mount, balance & patchplug tires at home (I've done 20 now)

I "rough balanced" the tires on the '53 MGTD I'm currently babysitting
and working on - to make it smooth enough to drive while I
troubleshoot other issues - but the tires are going onto the dynamic
balance at the first oppoertunity. I will be doing the balance - but
on proffessional equipment.

Yup. I know all about it.

Let's not argue here, but at least you have balanced wheels so you're one
of the very rare people who knows what you're talking about when you say
you wouldn't do it at home (because you don't like the job).

Most people only talk bull**** when they cry that they can't mount,
balance, and properly patchplug repair tires at home.

If they've never done it, then they're just talking out of their asses.
I know you've done it - although I think you used professional equipment.

Even with harbor freight Chinese crap tools, it's a piece of cake to
unmount and mount a tire, particularly a non-SUV passenger-car tire. The
wheels don't take a beating, even on my bimmer despite the fact the
crybabies assume they will (it's far more gentle than what a shop typically
does).

Those who cry that it is too much work, or that it's too expensive, or that
it takes too much time, or that it's dangerous, etc., are all just
crybabies who are just scared of their own shadow and afraid to get their
hands dirty.

It's so easy that I can do it in 15 minutes easily, although I am never in
a rush so the time is just to explain how easy it is. I scrub the wheels. I
remove the old weights. I match mount if possible the new tire. I am aware
of the drop center (thanks!). I replace the valves (that stupid valve stem
removal tool is a waste of money and space in the tool drawer - although
the valve seat removal tool is a godsend).

Anyway, tires are so easy that anyone who says they are not just proves
that they are an idiot.

The only thing you can't do easily at home is dynamically balance, but the
test for dynamic imbalance is free as you're already well aware. You just
don't know which tire it is!

3. Remove & repair a transmission (just did my 1st clutch, thanks to you!)
============
4. Measure & align what is designed to be adjusted (that's next on my list)

As an ex professional mechanic, I'll do toe-in adjustment as part ofa
front end repair - but it will go onto a REAL alignment machine before
it gets any miles on it - because I KNOW how important it is to get it
right - and how hard it is to do it right without proper equipment

I disagree but I understand. The reason people don't do each of the six
things is different for each item, where alignment makes the brain hurt.

It's not so much that there's trig involved, but it's more that the spec is
never in the same "thing" that you're measuring. For example, the damn
bimmer spec is in degrees of toe to the centerline. WTF.

It's not too hard to find the centerline, but you generally measure in
inches, not in degrees of toe.

At least camber is usually spec'd in degrees, which is what you measure.

Just like with tire-changing tools, every year the tools to measure camber
and toe (which is all the bimmer can adjust anyway) get better and cheaper.

You can do it with a plumb bob and ruler, but I prefer to measure toe in
inches and camber in degrees.

The hard part (other than the conversions of degrees to inches) is changing
toe without having to roll the car back and forth. Also, for the bimmer,
you need about 500 pounds of weight, but that's where all those gas cans
come in handy (filled with water).

5. Prep & paint an old vehicle (that is also next on my do-b4-I-die list)

As long as you don't mind driving your screw-ups (and there WILL be
several, at the very least - for sure -) go for it. I've painted a
few - and never been truly happy with any of my paint jobs. They've
been good - but not up to "my standards".

I completely understand. Remember, these cars are two decades old. Any
paint job will be a good paint job. It's like the old saying pilots have
for what a good landing is.

I think California just recently enacted a law saying you can't paint at
home anymore - but I'd have to check up on that with CARB as I haven't
spoken to them in a year (I call them up all the time and they're actually
very helpful engineers).

6. Remove & repair an engine (haven't done this - major downtime issue)

\Go for it. Start with a lawnmower motor. Then go to a simple older
engine like a sixties chevy, ford, or Chrysler six - on a "peoject
car" - or start with an old tractor that you don't need - but can use
when it's done for plowing snow or cutting grass - - -

I've taken apart some engines but the problem with a car is that it's a LOT
of stuff that has to come out, so there is a huge downtime that most people
just can't afford.

In summary, I've thought about the six jobs for years, and I've asked
people, but very few give an answer that makes sense. Your answers make
sense except for the refueling, but the rest make sense.

The main reasons, as I see them, summarized to fit on one line, are.
1. Gas: Most people just stop at a gas station; which is easy.
2. Tires: Most people pay $20 per tire; which is easy.
3. Trans: Most people just pay a mechanic $500 to $1000; which is easy.
---------- (these below I haven't done yet) ----------
4. Align: Most people's brains would explode with all the thinking.
5. Paint: A body shop will always do a far better job.
6. Engine: Nobody can afford the downtime for a daily driver.

[Clare Snyder]

On Sun, 5 Aug 2018 15:41:21 -0000 (UTC), Arlen Holder
wrote:

On 5 Aug 2018 07:31:19 GMT, Xeno wrote:

It always amazes me the dependence people place on those codes without
really understanding the *system* that is generating the codes and, in
most cases, the *limitations* of those systems.

I agree with both you and Scott that *most people* (not me, but most
people), when they see a sensor code, they replace the sensor.

It could be a temperature sensor for heaven's sake, and they replace the
sensor.

As I told Scott, I'm an EE so I know how to test a sensor, but in the case
of oxygen sensors, I've had five years' experience with the toyota and
bimmer where a bad sensor will make the FTP not set the related monitors
for hundreds of miles. IN the case of the toyota, it took about 400 miles,
and it took more than a thousand in the case of the bimmer.

In *both* cases, I took it to the smog referee and passed with flying
colors, even with the registers unset (since that's what the BAR smog
referee did in years past). They don't do that anymore, so you're stuck
now.

I know the FTP inside and out, and spoke to the BAR engineers who know it
even better than I do. I went over all the dozen conditions that an engine
must be in order for a monitor to be set.

Remember, in both cases, the bar smog referee PASSED the vehicle.

The problem is much more sinister than you seem to have experience with.
But I do agree with you that *most people* just throw parts at a problem.

What I find hilarious is what happens AFTER people throw parts at a
problem. Let's take the two corner cases, assuming, for example, that a
problem can have FIVE (for argument's sake) caususes:

1. If they guess right on the first pass, they claim that they are an utter
genius, and after that, for the rest of their lives, anyone who has that
same problem, they swear the answer is that first solution.
2. If they guess wrong, and have to replace all five parts, they swear that
the first four parts were bad, until they finally get to the right part.

Anyway, the main point here is that we all agree that throwing parts at a
problem is a crazy way to "fix things" but you have to admit a lot of car
problems are fixed that way.

I find the funniest "throwing parts" at a problem to be "brake warp".
I'm sure the intelligent ones here know that street rotors just don't warp.
So I will assume you know that.
(Nobody ever measures warp - but it's easy to measure warp which you do
measure for a head, for example.)


I'm going to call BS on this. Brake warpage is RARE - but certainly
not impossible or unheard of.
So what do the morons do when they get a brake-related vibration at speed?
They throw rotors (& sometimes pads & even bigger calipers) at it.

Guess what?
That solves the warp!
Instantly!

They *think* they're an utter genius.
They *think* they proved they had rotor warp.

Every brake vibration for the rest of their lives, is due to "warp".
Hehhehheh ....

Q: Why does this work?
A: Because the *short term* solution is *different* than the long-term one!

While brake-related judder can be caused by many things (look up the Tire
Rack vibration flow chart as just one example), let's assume that judder
was due to uneven pad deposition.

You can't measure that stuff (not with home equipment you can't).
So the rotors measure fine (not that anyone who thinks they warp measures
anything).

What happened in the case of "warp", is that there was uneven pad
deposition (let's say for this case), and so, replacing (or machining) the
rotors "solved" the problem but - get this - the warp comes back.


Pad deposit issues are the MAJOR cause of brake shake across north
america, followed by rotor corrosion (often related to pad deposits,
but not always) - but heat related warpage or corrosion related
parallelism problems are NOT uncommon.

Here in the rust belt, the corrosion issues are more common.

I have measured warpage in excess of .050" - on vehicles with NO
brake pulsation complaints as long as the caliper slides/pins are free
floating - but USUALLY when you have warpage it is BECAUSE the caliper
is not floating properly and the rotor has become severely overheated
(and then often differentially cooled - like hitting a water puddle)
I've seen a few real TACO rotors. Not many over 50 years - but enough
to make me say categorically that claims that rotors NEVER warp are
WRONG.
The guy who *thinks* the rotors warped is dumbfounded.

The short term solution solved the "warp", but the long term solution
didn't.
Q: What's the short term solution?
A: Change your rotors (or machine them or rebed them).

Q: What's the long term solution?
A: Change your braking habits.
Or the pad materials. Toyota had a situation years back where they
changed the composition of their semi metalic pads from brass filings
to iron - and all of a sudden they were replacing rotors by the pallet
load.

Going back to the previous (brass) pads solved the problem.

On my '90 Aerostar with the OEM spec semi metalic pads, the rotors
were always scrap LONG before the pads were worn out. I switched to a
performance carbon metallic pad, and for the first time I could lock
up the front brakes at ANY speed - and the rotors outlasted 2 sets of
pads - which lasted much longer than the previous OEM brakes.

My point is that, while I'm not a mechanic, and while I only have the
experience of the cars that I own or that friends/neighbors own, I
generally troubleshoot a problem to the UNDERSTANDING of teh cause of the
problem.

And I AM a (retired) mechanic - with LOTS of experience (including
teaching the trade and competition driving)

In the case of oxygen sensors, I know, from my experience with two old
vehicles, that an o2 sensor can be just bad enough to not set codes but to
take between 400 and 1000 miles to set all the registers - even as the
emissions are perfect.

If you can diagnose *that*, you'd be my hero!
Likewise, if you can suggest a working $100 smoke machine, I'd love you!

I've got a "stage effrcts" fog machine I've been meaning to adapt as a
diagnostic smoke machine. Paid about $30 for it.

[Vic Smith]

On Sun, 5 Aug 2018 09:37:55 -0700 (PDT), trader_4 wrote:

On Sunday, August 5, 2018 at 11:41:25 AM UTC-4, Arlen Holder wrote:
On 5 Aug 2018 07:31:19 GMT, Xeno wrote:


Anyway, the main point here is that we all agree that throwing parts at a
problem is a crazy way to "fix things" but you have to admit a lot of car
problems are fixed that way.


It may not be that crazy if you're paying $120 an hour for diagnosis.
It could be totally logical to replace two $30 parts, instead of
spending an hour figuring out which one it is. If you're doing it
yourself and the labor is free, then it changes the equation.

I've had 2 cars that threw an O2 sensor code. A Chevy, and my daughter's
Mitsu. In both cases new sensors - and nothing else - was the total fix.

[Arlen Holder]

On 5 Aug 2018 12:58:49 GMT, Clare Snyder wrote:

I'm going to call BS on this. Brake warpage is RARE - but certainly
not impossible or unheard of.

I don't disagree with you Clare as anything is possible.

Rotor "warp" is the classic case though of:
a. Most who "claim" disc warp don't actually measure anything.
a. Their short-term solution makes them feel like they are a genius
b. But the long-term solution is different if they truly warped.

I've noticed that most people who "scream" their rotor's warped, are only
screaming it because it continues to happen to them (fancy that), and that
they never seem to *measure* anything. They just assume rotors warp (as in
potato chip).

Pad deposit issues are the MAJOR cause of brake shake across north
america ...

Agreed.
That's why changing braking habits is critical, IMHO.

followed by rotor corrosion (often related to pad deposits

I'm in California. If you looked at those pictures of the transmission and
underside of the chassis of a 20 year old vehicle, you'll see corrosion
isn't much of an issue here luckily. But I grew up in the rust belt, so,
yeah, corrosion is a bitch as it can change runout.

but not always) - but heat related warpage or corrosion related
parallelism problems are NOT uncommon.

I won't argue. I read all the reports. I know what they say.
I just don't have the EXPERIENCE you have.

But I don't want to hear anyone talk about warp who didn't measure the
warp, which is easy to measure, since it's the same type of measurement you
use for a head (AFAIK).

Here in the rust belt, the corrosion issues are more common.

Yup. I've literally put my fingers through rocker panels on cars in the
rust belt. Not in California though. The environment is so easy here that
people's brains are warped from life being so easy.

I have measured warpage in excess of .050" - on vehicles with NO
brake pulsation complaints as long as the caliper slides/pins are free
floating - but USUALLY when you have warpage it is BECAUSE the caliper
is not floating properly and the rotor has become severely overheated
(and then often differentially cooled - like hitting a water puddle)

Steel doesn't get all that soft until reaching VERY HIGH temperatures.
I'm never gonna say they "can't" warp though (& I never did say that).

I was just using it as the classic case of throwing parts at the problem.

If someone has uneven pad deposition, then throwing rotors at the problem
year after year after year after year after year, is NOT the long-term
solution.

I've seen a few real TACO rotors. Not many over 50 years - but enough
to make me say categorically that claims that rotors NEVER warp are
WRONG.

Never say never.
I didn't mean to say or imply that they "can't" warp.
Just that it's a classic case of throwing parts at the problem.

The people who say rotors warp all the time on them say it year after year
after year after year. They even put LARGER rotors on the 4Runners (as
you're well aware) thinking that they were warping. So they spend HUNDREDS
of dollars on the wrong solution.

Not one of them measures the warp.
They simply throw parts at the problem.

And they think they're geniuses because the short term solution always
works. But then they come back and scream that the brakes suck because they
"warped again".

C'mon Clare ... you *must* have seen these millions of threads where guys
scream year after year that their rotors keep warping on them.

Or the pad materials. Toyota had a situation years back where they
changed the composition of their semi metalic pads from brass filings
to iron - and all of a sudden they were replacing rotors by the pallet
load.

True that some say you can get "race pads" which will reputedly "screap"
the uneven pad deposits off the rotors.

But you can just "rebed" the pads and it will do the same thing from my
experiences with deposition-related brake-related vibration at speed.

Going back to the previous (brass) pads solved the problem.

We have a huge thread on brake friction materials and testing of them.

My summary, after umpteen hours of research, is that it's not likely any
individual stands any chance of being able to compare two brake pads side
by side in his hands.

All he can do is "trust" the marketing (which I don't trust - and yes - I
was in marketing for a while) and trust that the cold/hot friction
coefficients apply to his driving style, vehicle, and terrain (it's hilly
here).

Me?
I dispense with all the marketing bull****. They can put a fleck of clay
and another fleck of metal and call it anything they want at that point
(which has been confirmed by my own personal phone conversations with the
Axxis/PBR/MetalMasters (bimmer) & Centric (toyota) engineers).

IMHO, there is more marketing bull**** in brake pads and rotors than in
politics (and you never will hear me speak of politics because I hate
bull****).

Everything is "performance". It's all marketing bull****.
The difference between "metalic" & "semimetalic" is marketing bull****.

Marketing can say anything they want (and they do).
All they need to do is put a fleck into the mix & they're home free.
(I get this information DIRECTLY from both Axxis & Centric engineers.)

Everything marketing says about street pads & rotors is, IMHO, bull****.
Almost nothing that most people say about pads & rotors is, IMHO, fact.

On my '90 Aerostar with the OEM spec semi metalic pads, the rotors
were always scrap LONG before the pads were worn out.

Luckily, it's trivial to measure rotors.
They either meet the minimum spec, or they don't.

And they're cheap too, nowadays.

I switched to a
performance carbon metallic pad, and for the first time I could lock
up the front brakes at ANY speed - and the rotors outlasted 2 sets of
pads - which lasted much longer than the previous OEM brakes.

I'm not gonna even touch the words "performance" "carbon" & "metallic".
Just not gonna.

And I AM a (retired) mechanic - with LOTS of experience (including
teaching the trade and competition driving)

In my experience with you over the years, on PRACTICAL stuff, you're almost
always, if not always dead right.

On theoretical stuff (like brake pads) we differ but not materially.
I think a lot of what is "said" about pads and rotors is bull****.
You seem to believe it.

That's fine. It's OK to not agree 100%, as I will always say I don't have
the experience you have, and I never will have that experience.

We just "trust marketing" hugely differently.
That's our main difference - and that's OK.

I don't trust a single word out of marketing (& yes, I was in marketing).

I've got a "stage effrcts" fog machine I've been meaning to adapt as a
diagnostic smoke machine. Paid about $30 for it.

I know. I know. I know.
I really really really need a good smoke machine.

The problem of course is that the smoke has to be copious and yet, not
harmful when deposited on cold metal inside the engine (I'm using a diesel
glow plug in a can of mineral oil at the moment but it doesn't make enough
smoke).

Then you need a slight positive pressure well regulated at very low single
or even half-digit psi.

In summary, a good home-use $100 smoke machine must:
a. Emit tons of non-harmful-to-the-engine when condensed smoke
b. At very low well-regulated psi (I think 1/2 psi to 2psi or so, max)

Anyone who makes a $100 good home smoke machine will make millions!

[Clare Snyder]

On Mon, 6 Aug 2018 02:45:58 -0000 (UTC), Arlen Holder
wrote:

On 5 Aug 2018 12:58:49 GMT, Clare Snyder wrote:

I'm going to call BS on this. Brake warpage is RARE - but certainly
not impossible or unheard of.

I don't disagree with you Clare as anything is possible.

Rotor "warp" is the classic case though of:
a. Most who "claim" disc warp don't actually measure anything.
a. Their short-term solution makes them feel like they are a genius
b. But the long-term solution is different if they truly warped.

I've noticed that most people who "scream" their rotor's warped, are only
screaming it because it continues to happen to them (fancy that), and that
they never seem to *measure* anything. They just assume rotors warp (as in
potato chip).

Pad deposit issues are the MAJOR cause of brake shake across north
america ...

Agreed.
That's why changing braking habits is critical, IMHO.

followed by rotor corrosion (often related to pad deposits

I'm in California. If you looked at those pictures of the transmission and
underside of the chassis of a 20 year old vehicle, you'll see corrosion
isn't much of an issue here luckily. But I grew up in the rust belt, so,
yeah, corrosion is a bitch as it can change runout.

but not always) - but heat related warpage or corrosion related
parallelism problems are NOT uncommon.

I won't argue. I read all the reports. I know what they say.
I just don't have the EXPERIENCE you have.

But I don't want to hear anyone talk about warp who didn't measure the
warp, which is easy to measure, since it's the same type of measurement you
use for a head (AFAIK).

Warpage is defined as irregular runout without change in thickness

Here in the rust belt, the corrosion issues are more common.

Yup. I've literally put my fingers through rocker panels on cars in the
rust belt. Not in California though. The environment is so easy here that
people's brains are warped from life being so easy.

I have measured warpage in excess of .050" - on vehicles with NO
brake pulsation complaints as long as the caliper slides/pins are free
floating - but USUALLY when you have warpage it is BECAUSE the caliper
is not floating properly and the rotor has become severely overheated
(and then often differentially cooled - like hitting a water puddle)

Steel doesn't get all that soft until reaching VERY HIGH temperatures.
I'm never gonna say they "can't" warp though (& I never did say that).

If it glows it can warp. I;ve seen a lot of rotors glowing red - and
a few almost orange hot - - you could see the glow in daylight.

I was just using it as the classic case of throwing parts at the problem.

If someone has uneven pad deposition, then throwing rotors at the problem
year after year after year after year after year, is NOT the long-term
solution.

I've seen a few real TACO rotors. Not many over 50 years - but enough
to make me say categorically that claims that rotors NEVER warp are
WRONG.

Never say never.
I didn't mean to say or imply that they "can't" warp.
Just that it's a classic case of throwing parts at the problem.

The people who say rotors warp all the time on them say it year after year
after year after year. They even put LARGER rotors on the 4Runners (as
you're well aware) thinking that they were warping. So they spend HUNDREDS
of dollars on the wrong solution.

Not one of them measures the warp.
They simply throw parts at the problem.

And they think they're geniuses because the short term solution always
works. But then they come back and scream that the brakes suck because they
"warped again".

C'mon Clare ... you *must* have seen these millions of threads where guys
scream year after year that their rotors keep warping on them.

Or the pad materials. Toyota had a situation years back where they
changed the composition of their semi metalic pads from brass filings
to iron - and all of a sudden they were replacing rotors by the pallet
load.

True that some say you can get "race pads" which will reputedly "screap"
the uneven pad deposits off the rotors.

But you can just "rebed" the pads and it will do the same thing from my
experiences with deposition-related brake-related vibration at speed.

Not if thr rotor rots out under the deposits - which is VERY common

Going back to the previous (brass) pads solved the problem.

We have a huge thread on brake friction materials and testing of them.

My summary, after umpteen hours of research, is that it's not likely any
individual stands any chance of being able to compare two brake pads side
by side in his hands.

We were through all this before. It's NOT all marketing BS. You CAN
get a good idea of what kind of results you will get by knowing the
composition of the pads - but the friction rating basically doesn't
tell you SQUAT.

All he can do is "trust" the marketing (which I don't trust - and yes - I
was in marketing for a while) and trust that the cold/hot friction
coefficients apply to his driving style, vehicle, and terrain (it's hilly
here).

Me?
I dispense with all the marketing bull****. They can put a fleck of clay
and another fleck of metal and call it anything they want at that point
(which has been confirmed by my own personal phone conversations with the
Axxis/PBR/MetalMasters (bimmer) & Centric (toyota) engineers).

IMHO, there is more marketing bull**** in brake pads and rotors than in
politics (and you never will hear me speak of politics because I hate
bull****).

Everything is "performance". It's all marketing bull****.
The difference between "metalic" & "semimetalic" is marketing bull****.

Marketing can say anything they want (and they do).
All they need to do is put a fleck into the mix & they're home free.
(I get this information DIRECTLY from both Axxis & Centric engineers.)

Everything marketing says about street pads & rotors is, IMHO, bull****.
Almost nothing that most people say about pads & rotors is, IMHO, fact.

On my '90 Aerostar with the OEM spec semi metalic pads, the rotors
were always scrap LONG before the pads were worn out.

Luckily, it's trivial to measure rotors.
They either meet the minimum spec, or they don't.

And they're cheap too, nowadays.

You fail to get the point. It wasn't "even" wear that you would
measure to determine if they required replacement. The rotors were
furrowed like a ploughed field - basically demolished - before the
pads were half worn - and it didn't stop worth crap.

I switched to a
performance carbon metallic pad, and for the first time I could lock
up the front brakes at ANY speed - and the rotors outlasted 2 sets of
pads - which lasted much longer than the previous OEM brakes.

I'm not gonna even touch the words "performance" "carbon" & "metallic".
Just not gonna.

Youi don't have to.

And I AM a (retired) mechanic - with LOTS of experience (including
teaching the trade and competition driving)

In my experience with you over the years, on PRACTICAL stuff, you're almost
always, if not always dead right.

On theoretical stuff (like brake pads) we differ but not materially.
I think a lot of what is "said" about pads and rotors is bull****.
You seem to believe it.

I told you what you were going to find out about the brakes from what
you were looking at, didn't i??? I TOLD you buying brakes by friction
rating was a fools errand. I told you to put OEM spec friction
material on for your applicaion, and forget about trying to out-think
the automotive engineers.

That's fine. It's OK to not agree 100%, as I will always say I don't have
the experience you have, and I never will have that experience.

We just "trust marketing" hugely differently.
That's our main difference - and that's OK.

I don't trust "marketing" any more than you do.

I don't trust a single word out of marketing (& yes, I was in marketing).

I've got a "stage effrcts" fog machine I've been meaning to adapt as a
diagnostic smoke machine. Paid about $30 for it.

I know. I know. I know.
I really really really need a good smoke machine.

I've never had one, and I've found all kinds of vacuum and fuel system
leaks without. They are definitely HANDY - but not 100% NECESSARY.

The problem of course is that the smoke has to be copious and yet, not
harmful when deposited on cold metal inside the engine (I'm using a diesel
glow plug in a can of mineral oil at the moment but it doesn't make enough
smoke).

Pretty pathetic excuse for a smoke generator, isn't it????

Then you need a slight positive pressure well regulated at very low single
or even half-digit psi.

In summary, a good home-use $100 smoke machine must:
a. Emit tons of non-harmful-to-the-engine when condensed smoke
b. At very low well-regulated psi (I think 1/2 psi to 2psi or so, max)

Anyone who makes a $100 good home smoke machine will make millions!
Only if they market it right - - - - - - - -

[Clare Snyder]

On Sun, 05 Aug 2018 23:51:15 -0400, Clare Snyder
wrote:


The problem of course is that the smoke has to be copious and yet, not
harmful when deposited on cold metal inside the engine (I'm using a diesel
glow plug in a can of mineral oil at the moment but it doesn't make enough
smoke).

Pretty pathetic excuse for a smoke generator, isn't it????

Then you need a slight positive pressure well regulated at very low single
or even half-digit psi.

In summary, a good home-use $100 smoke machine must:
a. Emit tons of non-harmful-to-the-engine when condensed smoke
b. At very low well-regulated psi (I think 1/2 psi to 2psi or so, max)


Try using a glycerine solution instead of the mineral oil - more
fog/smoke at lower temperature.
The smoke point of most oils is well over 300F - about 600F for
mineral oil?
Glycerine smoke machines work at about 290F IIRC.

[Arlen Holder]

On 5 Aug 2018 12:34:29 GMT, Clare Snyder wrote:

The big question I have is WHY would you fuel your "road vehicles" at
home if you have to buy it at a regular gas station and transport it
home, - unless you live a LONG ways from the fuel station?

That's super easy to answer, but everyone weighs things differently so your
weight on what I say below may be different.

a. I live many miles from any gas station - but that's not the reason.
b. I'm retired, so I basically only use the car for food & parts trips.
c. The wife HATES going to the gas station (& she hates Costco).
d. Costco has the best prices on gasoline out here
e. I can buy lots of storageable food at Costco just once a month
f. So I buy food and gas at the same time at Costco
g. 18 gallons easily lasts me more than a month in my car
h. But the wife uses 18 gallons in just two weeks

In the end, it works out perfectly, given that it's trivial to fuel a car
(if you haven't done it, you'll never know how freaking easy it is) and
it's just as trivial to fill 10 5-gallon jugs when you're already at Costco
getting food.

The hardest part is that you have to put the food in the back seat of the
sedan because the trunk is filled with cans (on purpose - so that they
don't move around on the windy hill).

So notice three things that others may not notice:
1. The wife never has to refill her car
2. I never have to make a gasoline run (I make a food run instead).
3. It's so easy to store jugs, fill jugs, & fill car, that it's not funny.

If it wasn't so easy, I might not do it, but it's one of those things that
is so simple that I can't think of any reason why I shouldn't do it.

It's sort of like someone asking why I throw clothes in the washing machine
instead of sending them out to be dry cleaned. It's so easy to wash at
home, that it's more effort to send them to the dry cleaner.

Same with refueling at home.
It's more convenient than refueling at a gas station.

[Arlen Holder]

On 5 Aug 2018 11:28:32 GMT, rbowman wrote:

'Repair kits' are popular around here and include a free flowing spout
and vent. Of course, they should only be used to repair older containers.

The asshole who mandated those spouts should spend eternity filling a
lawnmower with a full 5 gallon jug equipped with the monstrosity.

I've spent a lot of time on the phone with CARB who says that they don't
"design" the things ... they just mandate that the gas has to stay inside
them.

I joked back that it stays inside - it just won't come out.

I know all about the gas jug mods that people do (mostly to get air to come
in while the gas is pouring out).

Me?
The only mod I make is the trivial one that makes the cap child proof.
I just cut off the tap or remove the clip.

I don't ever use the spouts though.
They are nothing, to me, other than bung caps.

All I use is a 10 foot 1/2 inch clear vinyl hose.
I have four of them so that the siphoning is always dry.
(Each hose gives me five gallons - they dry out in a few hours.)

I also put a steel pipe that is a few inches longer than the depth of the
jug, but that's just finesse to keep the bottom of the hose at the bottom
corner. I also have a wooden triangle ramp that tilts the can slightly, but
again, that's just finesse. A long funnel with a few inches of flexible
half-inch hose on the output end completes the gas-station tack.

It's so easy and trivial to refuel that it's not funny.
Filling up is also easy, since I fill the car at the same time.

The main lesson I learned is that the more gas cans you pack in the trunk
the better, because I live on a very windy hill so the trunk has to be
packed such that nothing can tilt and everything will be at a 9% grade for
a very long time.

I generally flip all the cans upside down after filling to ensure they
don't leak.

All I need, in terms of gas caps, is a bung. The simpler the better.
It just needs a cap and nothing else.

Filling a lawn mower or other equipment I do the old school way from a one
or two gallon gas can (which I don't use for the cars).

Same with a chainsaw (I keep a German coke bottle of the right size to fill
the tank of the chainsaw.)

I have it down to a science. I used to stuff a rag in the top around the
hose, but then I realized the vapors are gonna leak when I remove4 the rag
anyway. The inside of a jug is about 22psi (depending on temp) for the
vapor pressure of gasoline, as I recall.

The real problem for most people is they can't keep a dozen gas jugs on
their lawn, but I'm rural so there's nobody to be bothered by the eyesore.

I do get comments when filling up at a gas station by morons though.
They think filling a gas jug is unsafe.

I wonder how many cars have plastic gas tanks nowadays?

[Arlen Holder]

On 5 Aug 2018 21:13:02 GMT, Clare Snyder wrote:

Try using a glycerine solution instead of the mineral oil - more
fog/smoke at lower temperature.
The smoke point of most oils is well over 300F - about 600F for
mineral oil?
Glycerine smoke machines work at about 290F IIRC.

Actually, I think it was glycerine. I don't remember, I lent it out and the
guy returned it sans the oil. So I don't remember.

But I agree that a good smoke machine needs lots of smoke at low psi.

Sounds easy - but it's hard to find one that is ready made or *easily*
converted for automotive use.

The one I made was just a new paint can with the glow plug mounted at top
to the battery and a compressor plus regulator but a normal regulator is
hard to get to the level of 1/2 to 2psi.

Some say a propane regulator is better - but you have to have one to know
and I don't so we made do with what we had handy.

[Clare Snyder]

On Mon, 6 Aug 2018 05:30:15 -0000 (UTC), Arlen Holder
wrote:

On 5 Aug 2018 21:13:02 GMT, Clare Snyder wrote:

Try using a glycerine solution instead of the mineral oil - more
fog/smoke at lower temperature.
The smoke point of most oils is well over 300F - about 600F for
mineral oil?
Glycerine smoke machines work at about 290F IIRC.

Actually, I think it was glycerine. I don't remember, I lent it out and the
guy returned it sans the oil. So I don't remember.

But I agree that a good smoke machine needs lots of smoke at low psi.

Sounds easy - but it's hard to find one that is ready made or *easily*
converted for automotive use.

The one I made was just a new paint can with the glow plug mounted at top
to the battery and a compressor plus regulator but a normal regulator is
hard to get to the level of 1/2 to 2psi.

Some say a propane regulator is better - but you have to have one to know
and I don't so we made do with what we had handy.
pick up a scrap barbq from the side of the road on one of your gas
runs. Or just cut the regulator off and take it home. They are
adjustable (under the cap) and are generally 7 inches of water - or
roughly 1/4 PSI

[rbowman]

On 08/05/2018 11:30 PM, Arlen Holder wrote:
The only mod I make is the trivial one that makes the cap child proof.
I just cut off the tap or remove the clip.

But, but, but.... It's for the children...

https://www.govtrack.us/congress/bills/110/hr814

Fortunately I don't have to deal with CARB, just stupid California ideas
that escape from the state.

[Arlen Holder]

On 5 Aug 2018 20:51:15 GMT, Clare Snyder wrote:

If it glows it can warp. I;ve seen a lot of rotors glowing red - and
a few almost orange hot - - you could see the glow in daylight.

I don't take anything at face value - I look things up.

However, I am not a metallurgist, so I first admit I didn't know if a rotor
"can" or "cannot" truly warp (as in potato chip) at street speeds - so I
looked up a few things about the temperature needed to cause true warpage
of a cast-iron rotor...

Raybestos says:
"Brake rotors do not warp from heat..."
http://www.hendonpub.com/resources/article_archive/results/details?id=1787

This says:
"Rotors are cast in extreme heat ¡X three to five times greater than
the most aggressive braking situation. Physically ¡§warping¡¨ a rotor
would require a similar application of extreme heat, which is
impossible."
http://www.brakeandfrontend.com/warped-rotors-myth/

This says:
"...the temperature required to make metal that resilient soft enough to
simply bend would be tremendous."
https://www.yourmechanic.com/article/why-do-brake-rotors-warp

This says that there are adverse effects starting at 1200dF:
"When this local temperature reaches around 1200 or 1300 degrees F.
the cast iron under the deposit begins to transform into cementite
(an iron carbide in which three atoms of iron combine with one atom
of carbon). Cementite is very hard, very abrasive and is a poor heat
sink. If severe use continues the system will enter a self-defeating
spiral - the amount and depth of the cementite increases with
increasing temperature and so does the brake roughness."
https://alconkits.com/technical-info/brake-tech/56-the-myth-of-warped-brake-discs

This says:
"in more than 40 years of professional racing, including the Shelby/Ford
GT 40s ¡V one of the most intense brake development program in history
- I have never seen a warped brake disc."
http://www.stoptech.com/technical-support/technical-white-papers/-warped-brake-disc-and-other-myths

These say the myth of warped rotors started in the 1970's:
http://www.brakeandfrontend.com/brake-tech-feature-8-myths-that-could-be-holding-you-back-from-performing-the-best-brake-job/
https://www.onallcylinders.com/2017/05/19/6-biggest-brake-rotor-myths-debunked/

This non-scientific thread, which we can quickly assume isn't scientific so
let's just take it as a reasonable point of view only, says that the
surface may get to 600dF but the rest of the rotor is at a lower
temperature than the surface.
https://www.reddit.com/r/cars/comments/3dxoli/the_myth_of_brake_rotor_warping/

I know you guys hate me for "book knowledge", but the answer on temperature
seems pretty clear so I will argue no further unless actual references are
supplied, as I already know tons of people *think* rotors warp, but it
seems that anyone who has actually measured it, apparently thinks not
(where true warpage would be easy to measure if you have the equipment to
measure head warp).

[Arlen Holder]

On 6 Aug 2018 07:16:52 GMT, rbowman wrote:

But, but, but.... It's for the children...

https://www.govtrack.us/congress/bills/110/hr814

Fortunately I don't have to deal with CARB, just stupid California ideas
that escape from the state.

I do think about things, before, during, and after I do them.
Life isn't without risks (e.g., nobody would own a chainsaw, if it was).

Whenever CARB tells me I shouldn't "modify" the can, I remind them over the
phone that they shouldn't have modified the gas can, which was working just
fine.

All we're doing is making it work for the job its intended to do.

I don't mind the gas staying inside the can.
It's the fact the gas doesn't come out that I mind.

To that end, I never use the spout (it's just a cap) for filling vehicles.

Besides, hefting five or six gallons and pouring for a few minutes into a
modern day vehicle isn't as easy as one might think. The funnel has to be
deep enough to flip the spring-operated lid and you have to hold the can
well above that so that it won't drip.

What I do is a simple two-step process.
a. Using a hose, I siphon almost all the gas into the vehicle, and, then,
b. Using a modified funnel, I pour the remaining dribble into the tank.

The reason for the second step isn't so much to get the gas, as it's only a
dribble since the pipe keeps the hose in the bottom corner where the wood
ramp keeps the gas just slightly elevated to put all the liquid into that
corner.

The reason for the second step is simply emissions. All that dribble will
vaporize, at about 22 psi (depending on temperature) vapor pressure. If I
lock the cap tightly, that vapor will NOT get into the atmosphere UNTIL I
open the cap, and then virtually all of that gas WILL go into the
atmosphere.

There's no way around that, other than to pour all that dribble into the
gas tank of the car while it's still liquid.

Plus, the vapor pressure of even 22 psi will bulge out the gas can (which
they can handle with aplomb, but why bother - I just spend an extra 30
seconds per gas can shaking out the liquid droplets - as an emissions
amelioration only).

That's the only reason the wide-mouthed funnel is needed. It's modified to
be longer than most funnels are simply by the addition of a flexible hose
on the end so that it stays inside the vehicle's gas opening so that one
person can easily use it on the dribble.

It's insanely easy to refuel a vehicle at home (if you have the space).

My approach is so simple it's easier than filling at a gas station.
1. I park next to a tall retaining wall that meets with the garage.
2. A stepladder allows me to put the gas jugs in the flat spot at top.
3. An optional wood ramp slightly elevates the front of the gas jug.
4. A rigid sleeve keeps the hose at the back lowest corner of the jug.
5. By mouth, I siphon the liquid, always having plenty of safety time.
6. Generally I go about my business to come back about 5 minutes later.
7. About 4-1/2 minutes later, the siphoning has stopped, gas in the bend.
8. Lifting only the hose from the top, I drain the remaining liquid.
9. Using the modified funnel, I shake out the dribble from the gas can.
10. I loosely recap the can (allowing fumes to evaporate) for storage.

If you can think of any step to *improve* this insanely easy process, let
me know. The only improvement step that I can come up with is "delivery"
and "storage" of a few hundred gallons using an electric pump from Granger
(yes, I know gas has an oxidation lifetime which is longer than just a
month or two).

55-gallon steel drums epoxy lined:
https://www.grainger.com/category/barrels-and-drums/barrels-drums-and-covers/drums-and-drum-handling-equipment/material-handling/ecatalog/N-1574Z1yzaej6

Electric pump for the barrels:
https://www.grainger.com/category/fuel-transfer-pumps/fuel-and-oil-transfer-pumps/pumps/ecatalog/N-11t0

Safety storage for the 5-gallon jugs:
http://www.safety1industries.com/product-reviews-blog/what-to-look-for-in-a-gas-storage-cabinet
https://www.uline.com/Grp_451/Safety-Storage
http://www.usasafety.com/gas-cylinder-cabinet-c-54.html

Even though it's far more convenient to refuel at home than at a gas
station, I'm always looking for ways to improve the process.

BTW, I used to put a rag around the top of the can, but I doubt that much
gas is escaping in the 5 minutes it takes to fuel from a jug, and, even
with the rag, I doubt it prevents much, if any - since - in the end - ALL
the "wetness" of the inside of the gas jug will go into the atmosphere no
matter what you do.

[Clare Snyder]

On Mon, 6 Aug 2018 14:54:13 -0000 (UTC), Arlen Holder
wrote:

On 5 Aug 2018 20:51:15 GMT, Clare Snyder wrote:

If it glows it can warp. I;ve seen a lot of rotors glowing red - and
a few almost orange hot - - you could see the glow in daylight.

I don't take anything at face value - I look things up.

However, I am not a metallurgist, so I first admit I didn't know if a rotor
"can" or "cannot" truly warp (as in potato chip) at street speeds - so I
looked up a few things about the temperature needed to cause true warpage
of a cast-iron rotor...

Raybestos says:
"Brake rotors do not warp from heat..."
http://www.hendonpub.com/resources/article_archive/results/details?id=1787

This says:
"Rotors are cast in extreme heat ¡X three to five times greater than
the most aggressive braking situation. Physically ¡§warping¡¨ a rotor
would require a similar application of extreme heat, which is
impossible."
http://www.brakeandfrontend.com/warped-rotors-myth/

This says:
"...the temperature required to make metal that resilient soft enough to
simply bend would be tremendous."
https://www.yourmechanic.com/article/why-do-brake-rotors-warp

This says that there are adverse effects starting at 1200dF:
"When this local temperature reaches around 1200 or 1300 degrees F.
the cast iron under the deposit begins to transform into cementite
(an iron carbide in which three atoms of iron combine with one atom
of carbon). Cementite is very hard, very abrasive and is a poor heat
sink. If severe use continues the system will enter a self-defeating
spiral - the amount and depth of the cementite increases with
increasing temperature and so does the brake roughness."
https://alconkits.com/technical-info/brake-tech/56-the-myth-of-warped-brake-discs

This says:
"in more than 40 years of professional racing, including the Shelby/Ford
GT 40s ¡V one of the most intense brake development program in history
- I have never seen a warped brake disc."
http://www.stoptech.com/technical-support/technical-white-papers/-warped-brake-disc-and-other-myths

These say the myth of warped rotors started in the 1970's:
http://www.brakeandfrontend.com/brake-tech-feature-8-myths-that-could-be-holding-you-back-from-performing-the-best-brake-job/
https://www.onallcylinders.com/2017/05/19/6-biggest-brake-rotor-myths-debunked/

This non-scientific thread, which we can quickly assume isn't scientific so
let's just take it as a reasonable point of view only, says that the
surface may get to 600dF but the rest of the rotor is at a lower
temperature than the surface.
https://www.reddit.com/r/cars/comments/3dxoli/the_myth_of_brake_rotor_warping/

I know you guys hate me for "book knowledge", but the answer on temperature
seems pretty clear so I will argue no further unless actual references are
supplied, as I already know tons of people *think* rotors warp, but it
seems that anyone who has actually measured it, apparently thinks not
(where true warpage would be easy to measure if you have the equipment to
measure head warp).
Different equipment required. Just a dialindicatoraznd stand, and a
micrometer.

Check for run-out on outer face then confirm no difference in
thickness. If the runout is not linear and there is no thickness
variation, it is warped.

The "cementite" formation is a lot more common than warpage

Warpage is less common on vented rotors than on solid rotors.

You don't need to take my word for it. There have been scientific
studies done - independent of the "marketing departments" of the brake
comnpanies that confirm dimensional instability (aka warpage) of grey
iron rotors is a "significant cause" of brake judder.

Read the study - and then decide who's right and who's wrong here - -
- -

From https://link.springer.com/article/10...665-012-0397-7
Where you can see allthe diagrams and charts etc related to the tests

Journal of Materials Engineering and Performance

April 2013, Volume 22, Issue 4, pp 1129–1135| Cite as


The Effect of Residual Stress on the Distortion of Gray Iron Brake
Disks


Thermal distortion of gray iron brake disks due to residual stress and
its effect on brake vibrations were studied. The residual stress of
heat- and non-heat-treated gray iron disks was measured using neutron
scattering. Dynamometer tests were performed to measure the friction
force oscillation caused by the disk runout during brake applications.
High-temperature tensile tests were carried out to find out possible
plastic deformation due to residual stress during brake applications.
The results showed that the average residual stress of the
heat-treated disk (47.6 MPa) was lower than that of the
non-heat-treated disk (99.6 MPa). Dynamometer tests at high
temperatures (up to 600 °C) indicated that the residual stress
pronounced the runout: the increase in disk runout after the tests for
the non-heat-treated sample was more than twice that for the
heat-treated sample. This difference correlated well with the neutron
scattering results and the dimensional changes after a separate vacuum
heat treatment. The high-temperature tensile tests showed severe
reductions in yield strength at 600 °C, suggesting that disks produced
with no stress relaxation could be deformed during severe braking.




Gray iron has been used to produce brake disks (or drums) since the
early stages of vehicle development. This is because gray iron has
good material properties for brake disks, such as high thermal
conductivity, good machinability, wear resistance, good castability,
excellent damping capacity, and low cost (Ref 1, 2). On the other
hand, it also has several undesirable properties for brake disks, such
as relatively high specific gravity, dimensional instability at high
temperatures due to residual stress, and inherent casting defects.
While other materials such as aluminum-based metal matrix composites
and ceramic-based carbon fiber composites have been developed as
alternatives for brake disks, most vehicles still rely on the
tribological properties of gray iron for brake disks, and much effort
has been devoted to improving the shortcomings of gray iron disks,
such as their excessive wear and corrosion, which are known to be root
causes of brake judder (Ref 3-5).

In particular, brake judder has been an important issue in vehicle
comfort in recent years, and various methodologies for reducing this
low-frequency vibration have been used (Ref 6-8). It is known that
disk warping or uneven disk thicknesses induce pulsation during brake
applications. While it is known that the system robustness is
important for reducing the amplification of the vibration, the major
source of brake-induced vibrations is the fluctuation of the friction
torque produced at the sliding interface as a result of the
dimensional variation of the disk. When the disk temperature is
increased by friction heat during braking, the heat often causes
dimensional instability of the disk, permanently modifying the runout
or disk thickness variation (DTV) of a disk and producing brake
judder. In particular, the residual stress, which is developed in a
cast as a result of different local cooling rates, is known to be one
of the important factors for reducing a disk’s propensity for
juddering, and stress relief by heat treatment is known to be an
effective method for ensuring the dimensional stability of a disk at
high temperatures.

Residual stress can be measured using several methods, including x-ray
scattering, hole drilling, indentation, and neutron scattering (Ref
9-11). The x-ray and neutron scattering methods are nondestructive,
while the hole-drilling and indentation methods are semi-destructive.
The measuring depth of an x-ray is very small (~5 µm), and this method
is only applicable to crystalline materials (Ref 9). The hole-drilling
method measures the strain around the hole during drilling, and the
indentation method is similar to a hardness measurement (Ref 9).
However, the hole-drilling and indentation methods do not allow
precise measurement of the residual stress in gray iron. This is
because the microstructure of gray iron is a mixture of graphite
flakes in a pearlitic steel matrix, and the multiphase nature of gray
iron often produces large amounts of scattering in the data (Ref 1,
2). On the other hand, the neutron scattering method measures the
residual stress of the ferritic phase in the gray iron along three
principal directions to a depth of 10 mm with good repeatability.

The residual stress of brake disks was investigated by Ripley and
Kirstein (Ref 12). They measured the residual strain using the neutron
scattering method and showed that the relaxation of the residual
stress in the disk could lead to disk distortion. Although the
residual stress induces elastic deformation at room temperature, the
tensile strength and hardness of gray iron decrease abruptly above 450
°C, so that the maximum value of the residual stress can reach the
yield stress of the gray iron at high temperatures (Ref 13, 14),
causing plastic deformation and permanent warping of the disk. In
order to remove the residual stress of the brake disks, therefore,
heat treatment to release the residual stress can be performed at high
temperatures.

In this study, the residual stress was measured using a neutron
scattering technique (Ref 9, 15, 16), and its correlation with the
judder propensity was investigated by examining the effect of heat
treatment on the microstructure of the gray iron and on the residual
stress. Heat treatment was carried out in a vacuum to investigate the
distortion produced by the relaxation of residual stress at high
temperatures. While the disk warping during heat treatment was
measured using a static DTV measurement unit, the dimensional change
of the brake disks during braking was monitored using a dynamic DTV
measurement unit.


Experimental Procedures


In order to investigate the dimensional change (or runout) of brake
disks due to the release of residual stress, three different
experiments were carried out. First, the residual strain of as-cast
gray iron disks was measured using a neutron scattering method.
Second, the change in runout was measured after vacuum heat treatment
at 580 °C. Finally, brake dynamometer tests were carried out to
simulate the release of residual stress due to the large friction heat
produced during severe braking. By comparing the three different test
results, the effects of the residual stress on the changes in runout,
DTV, and judder propensity were examined. Detailed experimental
procedures are described in the following sections.


Gray Iron Disks

Commercial gray cast iron disks for a passenger car were used in this
study. The carbon equivalent of the gray iron was 4.03, and the
detailed composition is given in Table 1. The width of the rubbing
surface of each disk was 57 mm. Each disk had 50 straight vanes, and
the disks were 302 mm in diameter and 28 mm in thickness. The vane
size was 19 mm (W) × 10 mm (H). An undercut was produced on the disk
surface near the hat portion to prevent possible corning. Two
different types of disks were prepared: heat-treated (Disk H) and
as-cast (Disk NH) disks. To relax the residual stress, heat treatment
was carried out by heating the disks at 580 °C for 5 h, furnace
cooling them from 580 to 300 °C at a rate of 40 °C/h, and air cooling
them from 300 °C to ambient temperature. The heat treatment schedule
is shown in Fig. 1. In order to reduce the effect of machining on the
residual stress, the heat treatment was carried out on the as-cast
disks before a final machining process.




The yield strength at elevated temperatures was measured using a
tensile testing machine (Instron 5881) according to an ASTM standard
procedure (AFS-ASTM E21). The specimens were wire cut from the rubbing
surface at the outer radius of Disk NH. The diameter of the specimens
was 6.25 mm, and the gage length was 32 mm. A schematic of the
specimen is shown in Fig. 2. The tensile tests were carried out at 25,
100, 200, 300, 400, 500, and 600 °C at a crosshead speed of 0.001
mm/s.



The microstructure of the gray iron was examined using an optical
microscope (Leica DM1-LM). The graphite lengths of the disk were
measured at outer, middle, and inner positions on the disk according
to AFS-ASTM A247. The Brinell hardness test was carried out using a 10
mm diameter steel ball at a load of 3,000 kg.


Residual Stress Measurement Using Neutron Scattering

The residual stress was measured from the diffraction peaks in the
three principal orientations (i.e., radial direction [RD], hoop
direction [HD], and normal direction [ND]) from a 2 mm (W) × 5 mm (L)
× 2 mm (D) gage volume of gray iron. The measurement was carried out
using a beam of neutrons from a bent perfect crystal (BPC) Si (220)
monochromator with a wavelength of 1.50-1.80 Å. The beam was scattered
in the sample, and the scattered neutrons were collected in a
position-sensitive device (PSD). A schematic of the neutron scattering
experiment is shown in Fig. 3.



The location in the disk of the specimen analyzed by neutron
scattering is shown in Fig. 4. The figure also includes a cross
section of the disk with the exact locations to be analyzed and the
three principal orientations with respect to the specimen geometry.
The reference specimen was also cut from the same location on the disk
and heat treated to achieve a stress-free state. The heat treatment
for the reference specimen was carried out by heating the specimen at
580 °C for 10 h, after which it was slowly cooled in the furnace to
ambient temperature.

Locations (A-D) used to measure residual stresses in the gray iron
disk, along with the three principal orientations (normal, hoop, and
radial)

The interplanar spacing of the (211) plane in ferrite was measured to
compare the residual stress in the disks (Ref 12). The residual strain
of the disk was calculated from the difference between the interplanar
spacing of the target disks and that of a reference specimen using Eq
1 (Ref 9)



e=(d-d 0 )/d 0 ,
e=(d-d0)/d0,

(1)
where d is the interplanar spacing obtained from the target disk and d
0 is the interplanar spacing of the reference specimen. The residual
strain was converted into residual stress using Eq 2 (Ref 12)



s i =E1+? [e ii +?1-2? (e xx +e yy +e zz )],
si=E1+?[eii+?1-2?(exx+eyy+ezz)],

(2)
where E is Young’s modulus (135.65 GPa) and v is Poisson’s ratio for
gray iron (=0.249). The elastic modulus and Poisson’s ratio were
measured using a resonance method according to an ASTM standard
(AFS-ASTM standard E1876-07) (Ref 12, 17).

Vacuum Heat Treatment

The vacuum heat treatment was carried out to simulate the release of
residual stress via disk distortion. The heat treatment schedule
consisted of furnace heating up to 580 °C followed by air cooling. The
disks were hung on a steel rod to prevent dimensional changes caused
by their own weight. Before and after the vacuum heat treatment, the
runout and DTV were measured using a static DTV measurement unit
(Describer-S™).


Dynamometer Tests

Dynamometer tests were carried out to simulate a hot judder mode using
a single-ended brake dynamometer (Link Engineering Model 3000). The
brake assembly used in this study comprised a commercial caliper with
a single piston and was developed for a midsize passenger car. The
test consisted of a preburnish, a 1st effectiveness check, a burnish,
a 2nd effectiveness check, and juddering. The purpose of this test
mode was to heat the disk above 580 °C and measure the changes in
runout, friction coefficient, and disk temperature. The detailed
dynamometer test procedure is listed in Table 2. The runout was
measured by a static DTV measurement apparatus (Describer-S™) before
and after the dynamometer tests. During the dynamometer tests, the
runout was recorded by a dynamic DTV measurement unit (Describer-D™).


Table 2
Dynamometer test sequence used in this study to simulate severe
braking conditions








Test sequence


No. of Stop


Stop condition



Pre burnish

10

From 80 ? 2 kph, 0.3 G and 100 °C (IBT)


Effectiveness check

5

From 160 ? 80 kph, 0.4 G and 100 °C (IBT)


Burnish

200

From 80 ? 2 kph at 0.3 G and 100 °C (IBT)


Effectiveness check

5

From 160 ? 80 kph, 0.4 G and 100 °C (IBT)


Judder

15

From 160 ? 50 kph at 100/200/300/400/500 °C (IBT) and at 0.2/0.35/0.5G



IBT, initial brake temperature; G, deceleration; kph, kilometers per
hour


Results and Discussion



Mechanical Properties of the Cast Iron

It is known that the mechanical properties of gray iron are strongly
affected by the lengths of the graphite flakes, which are in turn
determined by the composition and cooling rate during casting (Ref 1).
This is because the flaky graphite in the pearlitic matrix allows
stress to be concentrated at the flake tips, so that it plays a
crucial role in determining the tensile strength. The thermal
conductivity of gray iron is also determined by the size and the
distribution of the graphite flakes. This is an important property for
brake disks, as the thermal diffusivity of the disk is critical for
avoiding brake fade (loss of friction force at high temperatures) (Ref
18). The microstructure of the disk showed typical A-type graphite
flakes (AFS-ASTM A247 designation) embedded in a pearlite matrix (Fig.
5). The maximum graphite lengths of the disk were measured at outer,
middle, and inner positions on the disk according to AFS-ASTM A247.
They were 180.5, 200.8, and 243.7 µm, respectively. There were
slightly longer flakes in the inner section of the disk because of the
difference in the cooling speed during casting. The pearlite
microstructure of the disk, however, showed little difference among
the different locations in the disk. The morphology and distribution
of the graphite flakes and the pearlite microstructure also did not
change after heat treatments. The microstructure and hardness (HB) of
Disks NH and H did not change after heat treatment. The Brinell
hardness values of Disks NH and H were 210 and 205, respectively.



The tensile strength of the gray iron was measured as a function of
temperature. Figure 6 shows a drastic decrease of the yield strength
above 600 °C: the yield strength at room temperature is 257.9 MPa, and
it decreases to 66.7 MPa at 600 °C. Particularly noteworthy is the
finding that the residual stress in the cast can plastically deform
the disk during braking at elevated temperatures, leading to permanent
distortion of the disk.



Residual Stress in the Brake Disks

The residual stress in a cast is known to be affected not only by
locally different cooling speeds during casting but also by the final
machining processes. This is because while the residual stress present
in the cast is generated by the temperature gradient in the cast, it
can be released by removing the constraint imposed by the surface when
a portion of the surface is removed by machining. In order to study
the effect of heat treatment on thermal distortion of a gray iron
disk, the residual strain of the disk before and after the heat
treatment was measured after final machining.

From the residual strain measured using a neutron scattering method
for four different locations (Fig. 4) in the disk, residual stresses
were calculated along the three principal orientations (Fig. 7). The
figure shows the residual stresses for tension (positive) and
compression (negative), and no correlation was found between the
location in the disk, the principal orientation, and the heat
treatment with respect to the nature of the stress. On the other hand,
the amount of stress was relatively small at location A, presumably
due to the undercut (rain groove) near the hat section of the disk
produced by machining. While the residual stresses were obtained from
a single location in the disk and do not represent the stress
distribution of the whole disk, they provide information about the
relative amount of stress present in the disks with and without heat
treatment.


Residual stresses measured for the four different locations (A-D)
illustrated in Fig. 5 along the three different principal orientations

To analyze the effect of residual stress on the disk distortion, the
residual stresses in the normal orientation were compared first, as
the deformation is easier along the normal orientation as it is least
constrained compared to the other two directions. Figure 7 shows that
the residual stresses along the normal orientation were reduced after
heat treatment. The maximum residual stress before heat treatment was
found at location C and was 123.5 MPa. This was reduced to 57.5 MPa
after stress relief heat treatment, indicating possible permanent
deformation along the normal orientation when Disk NH is exposed to
heat during braking. This is because the residual stress at point C of
Disk NH is greater than the yield strength of gray iron at 600 °C. On
the other hand, the plastic deformation of the disk is not likely to
occur in Disk H, as the remaining residual stress after the heat
treatment is smaller than the yield strength at high temperatures.
Figure 7 also shows an inconsistent change of the stress state for
both Disks NH and H in the radial and hoop directions, which is
attributed to the vanes in the middle of the disks.


Simulation of Thermal Distortion by Heat Treatment Using a Vacuum
Furnace

The dimensional change (warping) of the disk was monitored after the
heat treatment in the furnace. This simulation was designed to
evaluate the possibility of adopting a prescreening process for disk
selection at an initial stage of brake system development by
simulating the temperature under a severe braking condition. The
distortions of Disks NH and H after the vacuum heat treatment are
shown in Fig. 8. Among the dimensional changes, the maximum difference
was about 8 µm in Disk NH at an angular position of 150°, while 2 µm
of dimensional change was observed in Disk H after heat treatment,
suggesting that there are beneficial effects of the heat treatment
resulting from the relief of residual stress. In particular, it was
interesting to find that the vacuum heat treatment produced warping in
Disk NH, while Disk H underwent a uniform dimensional change. This
indicates that the relatively large residual stresses of Disk NH in
the normal orientation play important role in the non-uniform
distortion of a disk during the release of the residual stress at
elevated temperatures.




Dimensional Change of the Disk During Dynamometer Tests

The distortion of the brake disk during brake applications was
analyzed by in situ monitoring of the runout during the dynamometer
tests. The brake applications for disk distortion (judder test
section) were carried out using the traditional performance checks and
a burnish procedure, as shown in Table 2. The temperature of the disk
during this test segment was increased by repeated brake applications
at different decelerations and initial brake temperatures (IBT).
Figure 9 shows the change in runout, the average coefficient of
friction, and the maximum disk temperatures recorded during brake
applications with different combinations of deceleration and IBT. This
figure shows that the maximum disk temperature and the friction level
are unchanged by the heat treatment of the disks. However, the runout
of Disk NH increased a lot compared to that of Disk H: the runout
increment was 15 µm for Disk NH and 6 µm for Disk H, suggesting that
the residual stress significantly affected the permanent distortion of
the gray iron disk. On the other hand, the small increase in the
runout of Disk H indicates that some residual stresses still remain in
the disk after the stress relief heat treatment used in this study.


Coefficient of friction, maximum disk temperature, and disk runout
measured in situ under different braking conditions during the
dynamometer tests using Disks H and NH

The increase in the runout was also examined by measuring the runout
values before and after the dynamometer test using a static DTV
measurement unit. Figure 10 shows an example of the profile of the
runout, presented as a function of the angular position on the disk.
This figure shows that the runout permanently increased by
approximately 5 µm after the high-temperature dynamometer test when
Disk H was used. The change in the runout was measured at three
different circumferential locations (edge, middle, and inner
positions) on the rubbing surface of the disk using a static DTV
measurement unit. Figure 11 summarizes the increase in disk runout
measured after dynamometer tests using Disks NH and H. It clearly
indicates that the effect of the residual stress in the normal
orientation is significant and that this effect is pronounced at the
edge location. This result suggests that the residual stress can
induce thermal distortion of a gray iron brake disk and may increase
the propensity of the disk to exhibit judder phenomena during brake
applications after repeated braking at elevated temperatures.


Runout of the disks as a function of angular position before and after
the high-temperature dynamometer tests for Disk H. The arrows indicate
the increase in runout measured at the edge of the disk




Increase in runout of the disks after high-temperature dynamometer
tests for Disks H and NH. Measurements were carried out for three
different locations (edge, middle, and inner, as shown in the inset)
using a static DTV measurement unit


Conclusions


The residual stress of gray iron disks was measured using a neutron
scattering method to understand the effect of residual stress on the
disk distortion. Two disks were used: one that had been subjected a
conventional heat treatment to release the residual stress and one
that had not. The disks were also heat treated in a vacuum furnace to
simulate their possible distortion at high temperatures. Dynamometer
tests were carried out, and the main emphasis was placed on the effect
of the residual stress on the increase in runout, which is one of the
main causes of brake judder. The results showed that the residual
stress in the normal orientation produces the runout change of the
disk after dynamometer tests at elevated temperatures. They also
showed a significant increase in disk runout for the non-heat-treated
disk, while the stress-relieving heat treatment reduced the disk
distortion. The simulation of disk runout, performed by simply
increasing the disk temperature in a vacuum furnace, shed light on a
possible mechanism for prechecking the residual stress of gray iron
disks in an early selection stage of brake components. The large
increase in the runout along the circumference near the edge indicates
the necessity for a more refined design of the casting process and the
disk shape.

[Clare Snyder]

On Mon, 6 Aug 2018 14:54:13 -0000 (UTC), Arlen Holder
wrote:

On 5 Aug 2018 20:51:15 GMT, Clare Snyder wrote:

If it glows it can warp. I;ve seen a lot of rotors glowing red - and
a few almost orange hot - - you could see the glow in daylight.

I don't take anything at face value - I look things up.

However, I am not a metallurgist, so I first admit I didn't know if a rotor
"can" or "cannot" truly warp (as in potato chip) at street speeds - so I
looked up a few things about the temperature needed to cause true warpage
of a cast-iron rotor...

Raybestos says:
"Brake rotors do not warp from heat..."
http://www.hendonpub.com/resources/article_archive/results/details?id=1787

This says:
"Rotors are cast in extreme heat ¡X three to five times greater than
the most aggressive braking situation. Physically ¡§warping¡¨ a rotor
would require a similar application of extreme heat, which is
impossible."
http://www.brakeandfrontend.com/warped-rotors-myth/

This says:
"...the temperature required to make metal that resilient soft enough to
simply bend would be tremendous."
https://www.yourmechanic.com/article/why-do-brake-rotors-warp

This says that there are adverse effects starting at 1200dF:
"When this local temperature reaches around 1200 or 1300 degrees F.
the cast iron under the deposit begins to transform into cementite
(an iron carbide in which three atoms of iron combine with one atom
of carbon). Cementite is very hard, very abrasive and is a poor heat
sink. If severe use continues the system will enter a self-defeating
spiral - the amount and depth of the cementite increases with
increasing temperature and so does the brake roughness."
https://alconkits.com/technical-info/brake-tech/56-the-myth-of-warped-brake-discs

This says:
"in more than 40 years of professional racing, including the Shelby/Ford
GT 40s ¡V one of the most intense brake development program in history
- I have never seen a warped brake disc."
http://www.stoptech.com/technical-support/technical-white-papers/-warped-brake-disc-and-other-myths

These say the myth of warped rotors started in the 1970's:
http://www.brakeandfrontend.com/brake-tech-feature-8-myths-that-could-be-holding-you-back-from-performing-the-best-brake-job/
https://www.onallcylinders.com/2017/05/19/6-biggest-brake-rotor-myths-debunked/

This non-scientific thread, which we can quickly assume isn't scientific so
let's just take it as a reasonable point of view only, says that the
surface may get to 600dF but the rest of the rotor is at a lower
temperature than the surface.
https://www.reddit.com/r/cars/comments/3dxoli/the_myth_of_brake_rotor_warping/

I know you guys hate me for "book knowledge", but the answer on temperature
seems pretty clear so I will argue no further unless actual references are
supplied, as I already know tons of people *think* rotors warp, but it
seems that anyone who has actually measured it, apparently thinks not
(where true warpage would be easy to measure if you have the equipment to
measure head warp).


Don't call it warping - call it "thermal distortion"

[Clare Snyder]

On Mon, 06 Aug 2018 14:38:48 -0400, Clare Snyder
wrote:

On Mon, 6 Aug 2018 14:54:13 -0000 (UTC), Arlen Holder
wrote:

On 5 Aug 2018 20:51:15 GMT, Clare Snyder wrote:

If it glows it can warp. I;ve seen a lot of rotors glowing red - and
a few almost orange hot - - you could see the glow in daylight.

I don't take anything at face value - I look things up.

However, I am not a metallurgist, so I first admit I didn't know if a rotor
"can" or "cannot" truly warp (as in potato chip) at street speeds - so I
looked up a few things about the temperature needed to cause true warpage
of a cast-iron rotor...

Raybestos says:
"Brake rotors do not warp from heat..."
http://www.hendonpub.com/resources/article_archive/results/details?id=1787

This says:
"Rotors are cast in extreme heat ¡X three to five times greater than
the most aggressive braking situation. Physically ¡§warping¡¨ a rotor
would require a similar application of extreme heat, which is
impossible."
http://www.brakeandfrontend.com/warped-rotors-myth/

This says:
"...the temperature required to make metal that resilient soft enough to
simply bend would be tremendous."
https://www.yourmechanic.com/article/why-do-brake-rotors-warp

This says that there are adverse effects starting at 1200dF:
"When this local temperature reaches around 1200 or 1300 degrees F.
the cast iron under the deposit begins to transform into cementite
(an iron carbide in which three atoms of iron combine with one atom
of carbon). Cementite is very hard, very abrasive and is a poor heat
sink. If severe use continues the system will enter a self-defeating
spiral - the amount and depth of the cementite increases with
increasing temperature and so does the brake roughness."
https://alconkits.com/technical-info/brake-tech/56-the-myth-of-warped-brake-discs

This says:
"in more than 40 years of professional racing, including the Shelby/Ford
GT 40s ¡V one of the most intense brake development program in history
- I have never seen a warped brake disc."
http://www.stoptech.com/technical-support/technical-white-papers/-warped-brake-disc-and-other-myths

These say the myth of warped rotors started in the 1970's:
http://www.brakeandfrontend.com/brake-tech-feature-8-myths-that-could-be-holding-you-back-from-performing-the-best-brake-job/
https://www.onallcylinders.com/2017/05/19/6-biggest-brake-rotor-myths-debunked/

This non-scientific thread, which we can quickly assume isn't scientific so
let's just take it as a reasonable point of view only, says that the
surface may get to 600dF but the rest of the rotor is at a lower
temperature than the surface.
https://www.reddit.com/r/cars/comments/3dxoli/the_myth_of_brake_rotor_warping/

I know you guys hate me for "book knowledge", but the answer on temperature
seems pretty clear so I will argue no further unless actual references are
supplied, as I already know tons of people *think* rotors warp, but it
seems that anyone who has actually measured it, apparently thinks not
(where true warpage would be easy to measure if you have the equipment to
measure head warp).
Aged castings, in general, tend to be more stable than "green "
castings as the stressed tend to reduce over time.

I have had rotors thet were "warped" right out of the box.
Confirmed by accurate measurement.
Machine THAT rotor true, and it will NOT warp in use.

The stresses came out of the casting after it was machined at the
factory.

In years past,castings were allowed to "age" or "rest" for a
significant period of time before final machining - and a lot of high
quality equipment was rough machined from an aged casting, then
allowed to age some more before the final precision machining was
done. The rough machining allowed the surface stresses to relieve so
the casting was fully relaxed and stable before final machining.
Themal "normalizing" can also be used - it speeds up the process.
So does "vibratory stress relief"

[[email protected]]

So does "vibratory stress relief"


.. " batteries not included " ? :-)

[Arlen Holder]

On 6 Aug 2018 11:38:48 GMT, Clare Snyder wrote:

From https://link.springer.com/article/10...665-012-0397-7
Where you can see allthe diagrams and charts etc related to the tests

Let me look at that paper, line by line...
https://link.springer.com/article/10...665-012-0397-7

My initial take?
a. The journal sounds decent:
Journal of Materials Engineering and Performance
b. The date sounds decent:
April 2013, Volume 22, Issue 4, pp 1129¡V1135
c. The topic? I'm not sure it's related yet:
The Effect of Residual Stress on the Distortion of Gray Iron Brake Disks

Gray Iron?
https://www.merriam-webster.com/dictionary/gray%20iron
"pig or cast iron containing much graphitic carbon which causes
its fracture to be dark gray"

Residual Stress?
https://en.wikipedia.org/wiki/Residual_stress
"Residual stresses are stresses that remain in a solid material after
the original cause of the stresses has been removed."

Abstract:
Thermal distortion of gray iron brake disks due to residual stress
and its effect on brake vibrations were studied.

Heat-treated discs did better than non-heat-treated discs
(on residual stress created runout).

They tested up to 600dC (1112dF) where "residual stress" made
runout worse,

That's it for the abstract.
I'm not sure this paper has anything to do with warp though (as in potato
chip).

I'll read the rest, but the abstract talks about "runout" which is a
completely different thing than warp (yes, I know that if a disc is warped,
it will also have runout - but they're still completely different things
because a disc can easily have runout without being warped - as in potato
chip).

[Arlen Holder]

On 7 Aug 2018 01:33:18 GMT, Arlen Holder wrote:

I'll read the rest, but the abstract talks about "runout" which is a
completely different thing than warp

Hi Clare,

You should be warned that I'm intelligent so I can *read* a peer-reviewed
scientific paper, unlike, it seems, most people, who can't comprehend what
a paper says. I've read a billion of them, so, bear in mind that I can
understand what the authors are trying to say, even as they use words
differently than we do.

Reading onward, I think the authors make a critical mistake in not defining
their terms, particularly when they use the word "warp" in this sentence,
which is the first time it appears in the paper...
"It is known that disk warping or uneven disk thicknesses
induce pulsation during brake applications."

Clearly it is well known that "warp" (as in potato) and "uneven thickness"
are two completely different things - which means that this particular set
of Asian authors (M. W. ShinG. H. JangJ. K. KimH. Y. KimHo Jang) are likely
ignorant of what "warp" means - or - they simply assume that it means
something that it doesn't mean (i.e., warp and thickness variation are
completely different things - they just are).

They then compound their errors in a sentence not far from that last horrid
sentence, saying "When the disk temperature is increased by friction heat
during braking, the heat often causes dimensional instability of the disk,
permanently modifying the runout or disk thickness variation (DTV) of a
disk and producing brake judder."

WTF?

These Asian guys don't seem to comprehend the English language. It's well
known that DTV and runout are two completely different things. They just
are. Everyone knows that (except them).

I think the reason they didn't care to use correct words is that they
didn't really care about any of those things - what they cared about, it
seems, was the effect of heat treating on residual stress which resulted in
a less pronounced runout measurement.

The end of the introduction concludes with the idiotically worded sentence:
"While the disk warping during heat treatment was measured using
a static DTV measurement unit..."
Which clearly shows they're using the word "warp" differently than we are
(simply because it's a fact that warp and DTV are two different things).

It appears that Ripley and Kirstein (Ref 12) paper might be more
appropriate since they showed that the relaxation of the residual stress in
the disk could lead to disk distortion. (We have to look at that paper to
find out how they defined "disk distortion" though.)

[Arlen Holder]

On 7 Aug 2018 01:50:38 GMT, Arlen Holder wrote:

You should be warned that I'm intelligent so I can *read* a peer-reviewed
scientific paper, unlike, it seems, most people, who can't comprehend what
a paper says.

I just posted a query to alt.usage.english as to why these particular Asian
authors can't seem to comprehend the difference between "warp" and "runout"
and "dtv", all of which they clearly equate in their paper - where all of
them are different things.
Why can't people figure out warp versus runout versus disc thickness variation
https://groups.google.com/forum/#!topic/alt.usage.english/Gqh_4X_FSw8

Unfortunately, since the Asian authors don't even comprehend what "warp"
actually means, that paper is useless for our purposes, IMHO, simply
because they never once measured warpage. Not once.

I completely understand how they *used* the term "warp"; but it's not the
same thing that I'm talking about.

What they measured was DTV and runout, and what they were caring about was
how heat treating affected those due to the interaction of residual stress
after subsequent heating.

This article, by apparently American authors, uses the terms the way I do:
http://www.brakeandfrontend.com/warped-rotors-myth/
Stop the Warped Rotors Myth and Service Brakes the Right Way

They advise:
"Starting today, remove ´warped rotor¡ from your vocabulary."

Where they discuss "lateral runout" and "disc thickness variation", which
are NOT the same thing as warp (as in potato).

They're just not.

[Arlen Holder]

On 6 Aug 2018 12:06:51 GMT, Clare Snyder wrote:

Don't call it warping - call it "thermal distortion"

That paper measured DTV and lateral runout.
Those are completely different things than "warp".

They just are.

I'm glad you found that paper - because it was interesting (it was really
about heat treating effects on DTV and lateral runout).

But that paper abused the term "warp" so it's useless as a paper about
warp.

[Xeno]

On 7/8/18 12:18 pm, Arlen Holder wrote:
On 7 Aug 2018 01:50:38 GMT, Arlen Holder wrote:

You should be warned that I'm intelligent so I can *read* a peer-reviewed
scientific paper, unlike, it seems, most people, who can't comprehend what
a paper says.

I just posted a query to alt.usage.english as to why these particular Asian
authors can't seem to comprehend the difference between "warp" and "runout"
and "dtv", all of which they clearly equate in their paper - where all of
them are different things.
Why can't people figure out warp versus runout versus disc thickness variation
https://groups.google.com/forum/#!topic/alt.usage.english/Gqh_4X_FSw8

Unfortunately, since the Asian authors don't even comprehend what "warp"
actually means, that paper is useless for our purposes, IMHO, simply
because they never once measured warpage. Not once.

I completely understand how they *used* the term "warp"; but it's not the
same thing that I'm talking about.

What they measured was DTV and runout, and what they were caring about was
how heat treating affected those due to the interaction of residual stress
after subsequent heating.

This article, by apparently American authors, uses the terms the way I do:
http://www.brakeandfrontend.com/warped-rotors-myth/
Stop the Warped Rotors Myth and Service Brakes the Right Way

They advise:
"Starting today, remove ´warped rotor¡ from your vocabulary."

Where they discuss "lateral runout" and "disc thickness variation", which
are NOT the same thing as warp (as in potato).

They're just not.


For christ's sake, WGAF?

--

Xeno

"The best way to make a fire with two sticks is to make sure one of them
is a match."
-- Will Rogers

[Clare Snyder]

On Tue, 7 Aug 2018 01:33:18 -0000 (UTC), Arlen Holder
wrote:

On 6 Aug 2018 11:38:48 GMT, Clare Snyder wrote:

From https://link.springer.com/article/10...665-012-0397-7
Where you can see allthe diagrams and charts etc related to the tests

Let me look at that paper, line by line...
https://link.springer.com/article/10...665-012-0397-7

My initial take?
a. The journal sounds decent:
Journal of Materials Engineering and Performance
b. The date sounds decent:
April 2013, Volume 22, Issue 4, pp 1129¡V1135
c. The topic? I'm not sure it's related yet:
The Effect of Residual Stress on the Distortion of Gray Iron Brake Disks

Gray Iron?
https://www.merriam-webster.com/dictionary/gray%20iron
"pig or cast iron containing much graphitic carbon which causes
its fracture to be dark gray"

Residual Stress?
https://en.wikipedia.org/wiki/Residual_stress
"Residual stresses are stresses that remain in a solid material after
the original cause of the stresses has been removed."

Abstract:
Thermal distortion of gray iron brake disks due to residual stress
and its effect on brake vibrations were studied.

Heat-treated discs did better than non-heat-treated discs
(on residual stress created runout).

They tested up to 600dC (1112dF) where "residual stress" made
runout worse,

That's it for the abstract.
I'm not sure this paper has anything to do with warp though (as in potato
chip).

I'll read the rest, but the abstract talks about "runout" which is a
completely different thing than warp (yes, I know that if a disc is warped,
it will also have runout - but they're still completely different things
because a disc can easily have runout without being warped - as in potato
chip).
Like I said - THERMAL DISTORTION - AKA warpage.
You have a different definition?

Rotors are GENERALLY made of grey iron - so it IS applicable.
Anything that causes movement in metal constitutes WARPAGE

[Clare Snyder]

On Tue, 7 Aug 2018 02:18:59 -0000 (UTC), Arlen Holder
wrote:

On 7 Aug 2018 01:50:38 GMT, Arlen Holder wrote:

You should be warned that I'm intelligent so I can *read* a peer-reviewed
scientific paper, unlike, it seems, most people, who can't comprehend what
a paper says.

I just posted a query to alt.usage.english as to why these particular Asian
authors can't seem to comprehend the difference between "warp" and "runout"
and "dtv", all of which they clearly equate in their paper - where all of
them are different things.
Why can't people figure out warp versus runout versus disc thickness variation
https://groups.google.com/forum/#!topic/alt.usage.english/Gqh_4X_FSw8

Unfortunately, since the Asian authors don't even comprehend what "warp"
actually means, that paper is useless for our purposes, IMHO, simply
because they never once measured warpage. Not once.

I completely understand how they *used* the term "warp"; but it's not the
same thing that I'm talking about.

What they measured was DTV and runout, and what they were caring about was
how heat treating affected those due to the interaction of residual stress
after subsequent heating.

This article, by apparently American authors, uses the terms the way I do:
http://www.brakeandfrontend.com/warped-rotors-myth/
Stop the Warped Rotors Myth and Service Brakes the Right Way

They advise:
"Starting today, remove ´warped rotor¡ from your vocabulary."

Where they discuss "lateral runout" and "disc thickness variation", which
are NOT the same thing as warp (as in potato).

They're just not.

Lateral runnout caused by thermal release of stress IS warpage.

If the damned thing runs true untill it gets hot, then has runout
without thickness variation, it HAS WARPED.

[Clare Snyder]

On Tue, 7 Aug 2018 02:21:51 -0000 (UTC), Arlen Holder
wrote:

On 6 Aug 2018 12:06:51 GMT, Clare Snyder wrote:

Don't call it warping - call it "thermal distortion"

That paper measured DTV and lateral runout.
Those are completely different things than "warp".

They just are.

I'm glad you found that paper - because it was interesting (it was really
about heat treating effects on DTV and lateral runout).

But that paper abused the term "warp" so it's useless as a paper about
warp.
OK smartass - define warpage .
Explain how lateral runout can happen without "warpage".
What, other than "warpage" would happen due to the relaxation of
captured stess in a casting due to application of heat????

What, other than "warpage" would cause lateral wunout in a
rotor???????

[rbowman]

On 08/06/2018 09:29 AM, Arlen Holder wrote:
It's insanely easy to refuel a vehicle at home (if you have the space).

I've been known to refuel the bikes but since I pass three gas stations
on the way to work I'm not about to start my own.

[Arlen Holder]

On 6 Aug 2018 20:23:09 GMT, Clare Snyder wrote:

Like I said - THERMAL DISTORTION - AKA warpage.
You have a different definition?

Rotors are GENERALLY made of grey iron - so it IS applicable.
Anything that causes movement in metal constitutes WARPAGE

Hi Clare,
Let's stop this nonsense.

That paper clearly and obviously measured two things:
a. Lateral runout
b. Disc thickness variation

Never once did that paper mention measurement of warp (as in potato chip).

I'm OK if people suggest a paper because I love to learn, but you have to
assume I'm intelligent enough to know that just googling for the word warp
connected with temperature doesn't mean the paper shows *anything* about
warp happening with temperature.

Maybe most people here deal with people who can't comprehend what a paper
says, but I can read almost any paper (I read Physics papers all the time)
and if I want to, I can comprehend what they say.

That paper said absolutely nothing about warp (as in potato chip).

I'm not chastising you. I *appreciate* that you tried to show that the disc
can get to a temperature that is hot enough to cause warp, as I had already
provided multiple references which said that such temperatures are
impossible in street use.

It's a valid question.

If someone can provide a paper that proves that such temperatures actually
commonly happen, I'll *read* (and comprehend) that paper.

But don't throw a paper at me that says absolutely zero about warp.
(Please assume I'm intelligent enough to read & comprehend the paper.)


I am NOT chastising you.
I'm just telling the truth - which is that paper had nothing to do with
warp even though the Korean authors used the word in the paper.

They were talking about:
a. Lateral runout, and,
b. Disc thickness variation
(among other things, like heat treating effects.)

[Arlen Holder]

On 6 Aug 2018 20:16:21 GMT, Xeno wrote:

For christ's sake, WGAF?

WGAF?

Why Give a ****?

There are good reasons to give a ****, since,
a) Clare suggested the paper, so I read it.
b) Are you chastising me for reading Clare's reference?
c) Or are you chastising me for *understanding* what it said?

Similarly, I don't know how many dollars are wasted every year on people
*thinking* their rotors warped, when they can't possibly warp (according to
the references I provided) simply because the temperatures needed are
impossible to attain for the entire rotor thickness.

Let's just assume that a billion dollars a year are *wasted* by morons who
can't comprehend the difference between disc thickness variation, lateral
runout, and true warp.

Worse - if I ever have a judder (and, at times, I do), then it matters a
lot that I *know* that warp can't possibly occur - so I know that the
long-term solution is not to buy "Tundra upgrades", which people spend
hundreds of dollars on that common but worthless imaginary panacea all the
freaking time!
http://www.toyota-4runner.org/3rd-gen-t4rs/84240-tundra-brake-upgrade.html

This is a group that is supposed to *understand* that which we fix, right?

If this group is supposed to *understand* a problem well enough to fix it,
then it matters that brake rotors just don't warp (they can't get hot
enough, based on the references I already quoted).

If someone can show a reference that shows that brake rotos can get hot
enough in street use to actually warp (as in potato chip), then I'll *read*
that reference.

You guys love to hate me for having "book knowledge", but having book
knowledge is better than having the wrong solution isn't it?

The reason it matters is that people implement the wrong solution because
they can't comprehend that rotors can't get hot enough to warp in street
use (according to multiple references - which hasn't been refuted by anyone
here).

Note, that Korean reference that Clare provided may have been translated
from Korean (we don't know yet), where this seems to be a portion of the
funding (apparently):
1.Department of Materials Science and EngineeringKorea University Seoul Republic of Korea
2.R&D Division Hyundai Motor Company and Kia Motors Corporation Hwaseong-si Republic of
Korea

[Arlen Holder]

On 6 Aug 2018 20:27:12 GMT, Clare Snyder wrote:

Lateral runnout caused by thermal release of stress IS warpage.

If the damned thing runs true untill it gets hot, then has runout
without thickness variation, it HAS WARPED.

Let's give up on this topic.
The same thing that is happening now, happened before.

It happens every time we discuss this topic.

People invariably "google" for "warp" and without comprehending the
reference, they throw whatever reference they find at me, as if I'm too
stupid to comprehend what it actually says.

Then, when I prove what the reference says, they change their definition of
"warp" because they feel that I chastised them and they don't like that.

So I'm sorry that the paper you provided doesn't say a single thing about
rotor warp. I really am sorry. I wish it did. But it just doesn't.

That's a fact.

Let's give up on this topic if the only way we can have an adult discussion
is that we have to use two different definitions of warp, where one
definition means anything you want it to mean, and where the other
definition is what all the references I quoted explain it to mean.
http://www.brakeandfrontend.com/warped-rotors-myth/
http://www.stoptech.com/technical-support/technical-white-papers/-warped-brake-disc-and-other-myths
https://oppositelock.kinja.com/brake-myths-what-to-expect-when-youre-expecting-to-st-1688020147

Here's just one quote from that last reference:
"They¢re not warped and they never were warped."

I won't respond further unless someone provides a reference that backs up
their point of view, as I've already provided plenty of references from
where I obtained my "book knowledge" that everyone seems to hate.

I don't mind a good healthy technical discussion, but I have no interest in
redefining what "warp" means when it's already very well defined in
technical terms.

If someone provides a paper that supports their viewpoint, I'll read it and
comment upon it - but otherwise - we're just spinning our wheels if we have
to change the definition of warp to prove that rotors do it in street use.

I apologize if I drop off (unless a reference is provided).

[Xeno]

On 7/8/18 2:08 pm, Arlen Holder wrote:
On 6 Aug 2018 20:16:21 GMT, Xeno wrote:

For christ's sake, WGAF?

WGAF?

Why Give a ****?

FFSGOY

waffle snipped

--

Xeno

"The best way to make a fire with two sticks is to make sure one of them
is a match."
-- Will Rogers

[Arlen Holder]

On 6 Aug 2018 20:54:54 GMT, rbowman wrote:

It's insanely easy to refuel a vehicle at home (if you have the space).

I've been known to refuel the bikes but since I pass three gas stations
on the way to work I'm not about to start my own.

I drive once a week, if that.
I go to Costco once a month, if that.
Costco has Tier 1 gas at the best price and no lines nowadays.
Costco is 40 miles away, but the gas stations are almost as far.
I have the room for storage - most people do not.
I have the height for fast flow - most people do not.
I have a dozen gas cans - most people do not.
I have four hoses - most people do not.
I have the modified funnel - most people do not.

In short, most people don't have the same situation that I have.
I've only been refueling for about 20 years.

Before that, I did what you do so I know the difference.

It's like mounting tires at home (which is so easy, it's not funny).
Anything who hasn't done it doesn't know what they're talking about.

Refueling is so trivially easy, that it's easier than going to the gas
station, IMHO. But I have the system down to a science where most people
probably are afraid of siphoning or they'd try to pour the gas using those
useless spouts, for example.

So they don't know what they're talking about.
I do.

[Clare Snyder]

On Tue, 7 Aug 2018 04:08:24 -0000 (UTC), Arlen Holder
wrote:

On 6 Aug 2018 20:16:21 GMT, Xeno wrote:

For christ's sake, WGAF?

WGAF?

Why Give a ****?

There are good reasons to give a ****, since,
a) Clare suggested the paper, so I read it.
b) Are you chastising me for reading Clare's reference?
c) Or are you chastising me for *understanding* what it said?

Similarly, I don't know how many dollars are wasted every year on people
*thinking* their rotors warped, when they can't possibly warp (according to
the references I provided) simply because the temperatures needed are
impossible to attain for the entire rotor thickness.

Which is a whole load of hooey.

All you need toi do is get it warm enough to release the stresses that
were not released from the casting before machining

Let's just assume that a billion dollars a year are *wasted* by morons who
can't comprehend the difference between disc thickness variation, lateral
runout, and true warp.

What is "true warp" as opposed to "lateral runout" when it is induced
by operational heating and coolong??? Semantics. That's all. and
bull**** from an electrical engineer trying to understand the
mechanics of materials.

Worse - if I ever have a judder (and, at times, I do), then it matters a
lot that I *know* that warp can't possibly occur - so I know that the
long-term solution is not to buy "Tundra upgrades", which people spend
hundreds of dollars on that common but worthless imaginary panacea all the
freaking time!
http://www.toyota-4runner.org/3rd-gen-t4rs/84240-tundra-brake-upgrade.html

You do NOT "KNOW" that the judder is not caused by thermally induced
lateral runout (aka - WARPAGE) - you just CHOSE TO BELIEVE it is
impossible.

This is a group that is supposed to *understand* that which we fix, right?

Been doing the fixing and the investigating for 50 years.

If this group is supposed to *understand* a problem well enough to fix it,
then it matters that brake rotors just don't warp (they can't get hot
enough, based on the references I already quoted).

Your references are BS.

If someone can show a reference that shows that brake rotos can get hot
enough in street use to actually warp (as in potato chip), then I'll *read*
that reference.

What do you mean "potato chip"? WARPAGE can cause lateral runout -
usually inconsistent lateral runout. - which is MY definition of
WARPAGE

You guys love to hate me for having "book knowledge", but having book
knowledge is better than having the wrong solution isn't it?

Not whenthe book knowlege is limited and does not agree with
documented real life experience.

Better no "knowlege" tha a load of BS.

The reason it matters is that people implement the wrong solution because
they can't comprehend that rotors can't get hot enough to warp in street
use (according to multiple references - which hasn't been refuted by anyone
here).


It has been refuted by me. Perhaps the cite was poorly weitten,and
poorly understood by you - but thermally induced runout of grey iron
roptors DOES happen - just as warpage of cyl heads (which. by the way,
do not reach NEARLY the temperatures rotors reach under hard braking--
- - -
Note, that Korean reference that Clare provided may have been translated
from Korean (we don't know yet), where this seems to be a portion of the
funding (apparently):
1.Department of Materials Science and EngineeringKorea University Seoul Republic of Korea
2.R&D Division Hyundai Motor Company and Kia Motors Corporation Hwaseong-si Republic of
Korea


I think the engineering was a whole lot better than the translation -
- - - and they were correct about a lot of things - disregarding poor
wording.

[Clare Snyder]

On Tue, 7 Aug 2018 04:25:26 -0000 (UTC), Arlen Holder
wrote:

On 6 Aug 2018 20:27:12 GMT, Clare Snyder wrote:

Lateral runnout caused by thermal release of stress IS warpage.

If the damned thing runs true untill it gets hot, then has runout
without thickness variation, it HAS WARPED.

Let's give up on this topic.
The same thing that is happening now, happened before.

It happens every time we discuss this topic.

People invariably "google" for "warp" and without comprehending the
reference, they throw whatever reference they find at me, as if I'm too
stupid to comprehend what it actually says.

Then, when I prove what the reference says, they change their definition of
"warp" because they feel that I chastised them and they don't like that.

So I'm sorry that the paper you provided doesn't say a single thing about
rotor warp. I really am sorry. I wish it did. But it just doesn't.

That's a fact.

Let's give up on this topic if the only way we can have an adult discussion
is that we have to use two different definitions of warp, where one
definition means anything you want it to mean, and where the other
definition is what all the references I quoted explain it to mean.
http://www.brakeandfrontend.com/warped-rotors-myth/

They missed the ONE thing that can cause lateral runout of a rotor -
warpage due to poor manufacturing whick allows casting stresses to be
released after machining - sometimes immediately, and sometimes after
they have been heat cycled. No extreme heat required, and NOTHING a
driver can do to prevent it. In the case of those that release the
stress after heat cycling, nothing a tech can do about it either -
other than machine it true -(once the stresses are ALL relieved, it
will not warp any further) after the fact.

When the stress comes out "in the box" or "on the shelf" machining the
rotor before installing has a 50/50 chance of solving the problem. The
rotor MAY be stable, or it may release more stress when heat cycled.

We had many cases of both at Toyota in the early to mid 80's. It was a
production problem which was eventually solved - and was only evident
on replacement rotors.

I had the same problems with the "economy" rotors from UAP (now NAPA)
- and it was on integrated front rotors (cast with hub) which
elimiunated ANY chance of it being an installation problem

I think 50 years experience actually diagnosing and repairing the
problems - and troubleshooting the issue for Toyota Canada beats your
"book learnin'" and cites from "automotive writers" - many of whom
couldn't tropubleshoot their way out of a wet paper bag if it was open
at both ends./
http://www.stoptech.com/technical-support/technical-white-papers/-warped-brake-disc-and-other-myths

Now you are believing the "marketing BS" from the
manufacturers/supplying who are saying the brake puilsation problems
are NEVER their fault - blame it on the mechanic or the driver.
Thought you didn't believe "marketing BS"
https://oppositelock.kinja.com/brake-myths-what-to-expect-when-youre-expecting-to-st-1688020147

Here's just one quote from that last reference:
"They¢re not warped and they never were warped."

ANd I say, in many cases they are right - but saying there is no such
thing as a warped rotor is total BS.
And the guy writing this last article could just as well be you. He's
no professional mechanic, and no materials engineer,

I won't respond further unless someone provides a reference that backs up
their point of view, as I've already provided plenty of references from
where I obtained my "book knowledge" that everyone seems to hate.

The references you have quoted are NOT scientific reviews - they have
no more (and generally less) veracity than the cite I provided for
you (which, by the way WAS - TOTALLY on topic.

I don't mind a good healthy technical discussion, but I have no interest in
redefining what "warp" means when it's already very well defined in
technical terms.


Give me that definition. I've given you what I accept as the
definition of warpage in this case - thermally induced lateral runout
without thickness variation, caused by the release of cast-in stresses
in the rotor.
If someone provides a paper that supports their viewpoint, I'll read it and
comment upon it - but otherwise - we're just spinning our wheels if we have
to change the definition of warp to prove that rotors do it in street use.

I apologize if I drop off (unless a reference is provided).


You can forget about any more help from me. Bye Bye

[Clare Snyder]

On Tue, 7 Aug 2018 04:08:23 -0000 (UTC), Arlen Holder
wrote:

On 6 Aug 2018 20:23:09 GMT, Clare Snyder wrote:

Like I said - THERMAL DISTORTION - AKA warpage.
You have a different definition?

Rotors are GENERALLY made of grey iron - so it IS applicable.
Anything that causes movement in metal constitutes WARPAGE

Hi Clare,
Let's stop this nonsense.

That paper clearly and obviously measured two things:
a. Lateral runout
b. Disc thickness variation

Never once did that paper mention measurement of warp (as in potato chip).

I'm OK if people suggest a paper because I love to learn, but you have to
assume I'm intelligent enough to know that just googling for the word warp
connected with temperature doesn't mean the paper shows *anything* about
warp happening with temperature.

Maybe most people here deal with people who can't comprehend what a paper
says, but I can read almost any paper (I read Physics papers all the time)
and if I want to, I can comprehend what they say.

That paper said absolutely nothing about warp (as in potato chip).

I'm not chastising you. I *appreciate* that you tried to show that the disc
can get to a temperature that is hot enough to cause warp, as I had already
provided multiple references which said that such temperatures are
impossible in street use.

It's a valid question.

If someone can provide a paper that proves that such temperatures actually
commonly happen, I'll *read* (and comprehend) that paper.

But don't throw a paper at me that says absolutely zero about warp.
(Please assume I'm intelligent enough to read & comprehend the paper.)


I am NOT chastising you.
I'm just telling the truth - which is that paper had nothing to do with
warp even though the Korean authors used the word in the paper.

They were talking about:
a. Lateral runout, and,
b. Disc thickness variation
(among other things, like heat treating effects.)
Which if you understand ANYTHING about castings, metalurgy, and
materials science, is EXACTLY what we are talking about.

Good Bye.

[rbowman]

On 08/07/2018 03:23 PM, Arlen Holder wrote:
It's like mounting tires at home (which is so easy, it's not funny).
Anything who hasn't done it doesn't know what they're talking about.

I'll give you a call the next time I reshoe the DR650. I don't know why
but getting the bead to seat on the Kenda front was a bitch last time
around. Dunlop D606's just fall into place.

[trader_4]

On Tuesday, August 7, 2018 at 8:52:22 PM UTC-4, Clare Snyder wrote:
On Tue, 7 Aug 2018 04:25:26 -0000 (UTC), Arlen Holder
wrote:

On 6 Aug 2018 20:27:12 GMT, Clare Snyder wrote:

Lateral runnout caused by thermal release of stress IS warpage.

If the damned thing runs true untill it gets hot, then has runout
without thickness variation, it HAS WARPED.

Let's give up on this topic.
The same thing that is happening now, happened before.

It happens every time we discuss this topic.

People invariably "google" for "warp" and without comprehending the
reference, they throw whatever reference they find at me, as if I'm too
stupid to comprehend what it actually says.

Then, when I prove what the reference says, they change their definition of
"warp" because they feel that I chastised them and they don't like that.

So I'm sorry that the paper you provided doesn't say a single thing about
rotor warp. I really am sorry. I wish it did. But it just doesn't.

That's a fact.

Let's give up on this topic if the only way we can have an adult discussion
is that we have to use two different definitions of warp, where one
definition means anything you want it to mean, and where the other
definition is what all the references I quoted explain it to mean.
http://www.brakeandfrontend.com/warped-rotors-myth/

They missed the ONE thing that can cause lateral runout of a rotor -
warpage due to poor manufacturing whick allows casting stresses to be
released after machining - sometimes immediately, and sometimes after
they have been heat cycled. No extreme heat required, and NOTHING a
driver can do to prevent it. In the case of those that release the
stress after heat cycling, nothing a tech can do about it either -
other than machine it true -(once the stresses are ALL relieved, it
will not warp any further) after the fact.

When the stress comes out "in the box" or "on the shelf" machining the
rotor before installing has a 50/50 chance of solving the problem. The
rotor MAY be stable, or it may release more stress when heat cycled.

We had many cases of both at Toyota in the early to mid 80's. It was a
production problem which was eventually solved - and was only evident
on replacement rotors.

I had the same problems with the "economy" rotors from UAP (now NAPA)
- and it was on integrated front rotors (cast with hub) which
elimiunated ANY chance of it being an installation problem

I think 50 years experience actually diagnosing and repairing the
problems - and troubleshooting the issue for Toyota Canada beats your
"book learnin'" and cites from "automotive writers" - many of whom
couldn't tropubleshoot their way out of a wet paper bag if it was open
at both ends./
http://www.stoptech.com/technical-support/technical-white-papers/-warped-brake-disc-and-other-myths

Now you are believing the "marketing BS" from the
manufacturers/supplying who are saying the brake puilsation problems
are NEVER their fault - blame it on the mechanic or the driver.
Thought you didn't believe "marketing BS"
https://oppositelock.kinja.com/brake-myths-what-to-expect-when-youre-expecting-to-st-1688020147

Here's just one quote from that last reference:
"Theye not warped and they never were warped."

ANd I say, in many cases they are right - but saying there is no such
thing as a warped rotor is total BS.
And the guy writing this last article could just as well be you. He's
no professional mechanic, and no materials engineer,

I won't respond further unless someone provides a reference that backs up
their point of view, as I've already provided plenty of references from
where I obtained my "book knowledge" that everyone seems to hate.

The references you have quoted are NOT scientific reviews - they have
no more (and generally less) veracity than the cite I provided for
you (which, by the way WAS - TOTALLY on topic.

I don't mind a good healthy technical discussion, but I have no interest in
redefining what "warp" means when it's already very well defined in
technical terms.


Give me that definition. I've given you what I accept as the
definition of warpage in this case - thermally induced lateral runout
without thickness variation, caused by the release of cast-in stresses
in the rotor.
If someone provides a paper that supports their viewpoint, I'll read it and
comment upon it - but otherwise - we're just spinning our wheels if we have
to change the definition of warp to prove that rotors do it in street use.

I apologize if I drop off (unless a reference is provided).


You can forget about any more help from me. Bye Bye

One fundamental problem here is the two of you have different definitions
of what warpage of a rotor is. IDK if that Korean paper defined it, they
should. But it sounds like their definition is similar to Clares, while
Arlen says that warping has to be like a wavy, potato chip effect.
Would seem to me that any change in the rotor away from it's true shape
that causes problems could be called warpage. If you don't call it that,
what would it be called? Deformation? Never heard anyone call it that.

[Clare Snyder]

On Tue, 7 Aug 2018 19:06:34 -0600, rbowman wrote:

On 08/07/2018 03:23 PM, Arlen Holder wrote:
It's like mounting tires at home (which is so easy, it's not funny).
Anything who hasn't done it doesn't know what they're talking about.

I'll give you a call the next time I reshoe the DR650. I don't know why
but getting the bead to seat on the Kenda front was a bitch last time
around. Dunlop D606's just fall into place.

I can think of lots of tires Arlrn would NEVERget mounted on
his aparatus.

[rbowman]

On 08/07/2018 08:05 PM, Clare Snyder wrote:
On Tue, 7 Aug 2018 19:06:34 -0600, rbowman wrote:

On 08/07/2018 03:23 PM, Arlen Holder wrote:
It's like mounting tires at home (which is so easy, it's not funny).
Anything who hasn't done it doesn't know what they're talking about.

I'll give you a call the next time I reshoe the DR650. I don't know why
but getting the bead to seat on the Kenda front was a bitch last time
around. Dunlop D606's just fall into place.

I can think of lots of tires Arlrn would NEVERget mounted on
his aparatus.


I don't do tubeless. I have fond memories of getting a new set of tires
for the Harley from an indie. I'd done business with him before and he
was capable, plus he had a big compressor and had replumbed the air
lines to get maximum volume and had one of those tourniquets. The sun
was setting in the west as he tried to get the bead to catch. At least
with tubed tires the bead will seat sooner or later.