"jim rozen" wrote in message
...
In article , Harold and Susan Vordos says...

It's one of those things that you can go a life time without and swear it
makes no difference.. Bottom line is how much you expect from your
machine,
your setup, your ability. I've always carried a definite edge over
others
because I cared enough to learn early on. You're likely to find someone
that has the opinion that it doesn't matter. I think it does. I may
sound like an ass, but I can tell you all I need to know about a guy's
ability on a machine by looking at his lathe tools. When they look like
they've been gnawed out by a gopher, I rarely expect anything of
substance
to come from the person, and I'm rarely disappointed.

Ah Haa! So this is why you don't like insert tools - you can't
use that as a metric any more! :^)

Jim

Chuckle!

Actually, I do use them, Jim. A lot more than I admit to. My favorite is
the RB negative rake holder that cuts positive. The inserts are a modified
triangle and have chip breakers diamond ground such that the tool cuts
positive. I also have heads for boring bars that use the same type, but
smaller, insert. They are likely the finest insert tools I've ever owned.
They were particularly valuable to me when I used to run the metering pumps
for a blood analyzing machine for the pharmaceutical industry, where I ran
hundreds of components with a half thou tolerance. I also have
insert tooling for my tracer, which, just like running a CNC, really demands
such tooling.

One thing that turns me off is anyone that turns to insert tooling and
refuses to learn to grind either HSS or brazed tools. Until such time one
knows and understands cutting geometry and how it applies to success,
they're kidding themselves. Any damned hack can load parts in a machine
and apply a tool provided by others. It takes skill and talent to do it the
hard way, and it's all very much a part of becoming a machinist in the true
sense of the word. To substitute the learning curve with insert tools is a
huge disservice to the operator.

I realize that my philosophy may not fit today's circumstances, what with
CNC machines having replaced manual machines almost entirely, but for the
most part, we home shop types don't have the luxury of CNC's, so
shortcutting the learning process becomes a huge stumbling block.

Harold

"Charles A. Sherwood" wrote in message
...
conventional pedestal grinder for grinding toolbits. Knowing how to
properly dress the wheel becomes quite important when you grind this
way.
It must run smooth and true, for it becomes your reference point.

OK. Maybe you guys can tell me how to dress a new 10 inch grinding wheel!

I have a baldor 10 inch grinder and I installed new name brand wheels
from MSC. I have two different wheel dressors (0-10) (10+) and I still
cannot get the wheels round. I even tried using a diamond point and ruined
it.

So, How do you dress a new 10 inch grinding wheel ??

chuck

Nothing you're saying makes a lot of sense, Chuck. Can you fill us in on
what you're doing, and how? The very notion that you ruined a diamond
point tells me something is woefully wrong.

Please clarify your wheel dressers, too. I have no clue what the
designations mean. (0-10) and (10+). I can only assume you're making a
reference to the size of the dresser as it applies to the wheel size.

If you are trying to shape and true your wheels with star type dressers,
you're likely to not like what I have to say about them. Before
expounding, I'd like to comment that there is no better way to prepare a
wheel to cut than with such a dresser, but they present some serious
problems in their application. For one, they're difficult to apply such
that you can get a wheel running smoothly. A bouncing wheel is pretty much
useless for sharpening tools. There are better ways to true wheels, which
we'll discuss as quickly as I understand more about your problem.

For sharpening your tool bits it is important that you have aluminum oxide
wheels, *never* silicon carbide, be it green or black.

Tell us more about your setup and lets talk. (Sorry I didn't get back to
your email last weekend. I came down with a killer cold and spent two days
in bed. Life sucks!)

Harold

Can you fill us in on what you're doing, and how?

I have a baldor 10 inch grinder with new norton grinding wheels.
(one course and one fine) purchased from MSC.

I have two Enco grinding wheel dressers. One is a #0 and is
rated for wheels 0-10 inchs. The other is a #1 and is rated
for wheels 10-16 inchs. They are not called star dressers
in the catalog but I think they are star dressers.

I also have a 1 inch square Silicon carbide wheel dresser.

I cannot make the grinding wheels round using any of the above
tools. I can remove grit from the wheel but it still does not
make it round. At low speed I can see noticable runout.

I even tried to use a diamond point intended for the surface
grinder to make them concentric and it didn't seem to work very well.
I was holding it by hand.

How do I dress the wheels to make them round?

Since the wheels are not round, they are difficult to use
for anything except rough grinding.

hope this is clearer?

chuck

In article , Harold and Susan Vordos says...

I realize that my philosophy may not fit today's circumstances, what with
CNC machines having replaced manual machines almost entirely, but for the
most part, we home shop types don't have the luxury of CNC's, so
shortcutting the learning process becomes a huge stumbling block.

But the flip side of this is that one can be skilled and adept at
grinding tools by hand, and still have *zero* experience or skills
at NC programming. I had pretty much zero there when I first went
to work at that night production job.

Most of the guys there didn't even know you *could* make cutting
tools by hand! But they knew G-code stuff inside and out. I learned
enough in my couple of years there to keep me from being a menace
to myself!

Jim


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==================================================
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==================================================

"Charles A. Sherwood" wrote in message
...
Can you fill us in on what you're doing, and how?

I have a baldor 10 inch grinder with new norton grinding wheels.
(one course and one fine) purchased from MSC.

I have two Enco grinding wheel dressers. One is a #0 and is
rated for wheels 0-10 inchs. The other is a #1 and is rated
for wheels 10-16 inchs. They are not called star dressers
in the catalog but I think they are star dressers.

If they have segmented pieces that spin, that's what they are. Jim likes
'em, and even ol' teenut used to extol their virtues, but I'll put my
grinding experience up against their opinions any time anyone wants to have
a discussion. As I said, there is no better way to prepare a wheel for
cutting. By their nature, they leave very sharp grain when properly applied.
Problem is, it's hard to get a wheel running true. In order for them to
function properly, they require a given load, otherwise all you do is grind
away the components. They dress by hammering the wheel, breaking it into
fine particles. Assuming you can get the wheel running dead true, you
can then bear down adequately for the dresser to do a good job, but you can
waste a lot of wheel getting there, and it's not all that hard to get the
wheel to start bouncing again while you're using it. As I said, I avoid
them totally. Don't even own one, nor do I care to. If I had a large 3
phase grinder for grinding on weldments, I'd likely have a different
attitude. They're great for that application.

I also have a 1 inch square Silicon carbide wheel dresser.

That's the tool I thought I'd have to explain to you.

You can't bear down with them if you want a wheel to come true. If you
have a work rest, this is one place where it can pay benefits. You place
the dressing stick on the rest, picking a sharp corner, lightly touching the
grinding wheel, which should be at operating speed. The highs only will
make contact with the stick and slowly be lowered until you finally have
full contact all around. If you crowd the dressing, you tend to encourage
the wheel to shrink, but not get corrected. From this you should understand
that it takes a light hand. You can't horse getting the wheel running true.
Once it is running true you can aggressively remove more wheel with
reasonable results, though. Remember: A light touch.

Assuming your wheel is out a considerable amount, and you'd like to true it
up with a diamond first, that works fine, too, but you have to use the same
principle, lightly applying the diamond so only the highs get removed. As
quickly as you have the wheel running true, you should change to your
dressing stick. Diamond dressed wheels don't lend themselves well at all to
offhand grinding because the surface is way too smooth. Exactly the opposite
from what a star dresser does. A light touchup with a dressing stick will
usually prepare the wheel for quite good grinding performance. Avoid the
use of the little dressing sticks that are 1/4" x 1/2" x 3" in size, and are
one solid piece. They are boron carbide, and while they're even harder than
the silicon carbide dressing sticks, unless they are very sharp, they tend
to dull the grain excessively, so your wheel cuts quite hot----very similar
to a wheel prepared with a diamond, in fact.


I cannot make the grinding wheels round using any of the above
tools. I can remove grit from the wheel but it still does not
make it round. At low speed I can see noticable runout.

You may see some real strange conditions as wheels spin up and down. Don't
worry too much about that, just make sure that when your wheel is up to
speed, it runs true. Often the imbalance of larger wheels will cause some
vibration that makes them look like they're running out a lot more than they
really are. If you find your wheels vibrate excessively, it's not
impossible to have ended up with wheels that are not well balanced.
Precision grinders have provisions for balancing the wheels, but pedestal
grinders usually do not.

I trust you know to use the proper flanges, and to always run the blotters.
You risk fracturing wheels when you mount them without. Hopefully you
also understand how to "ring" a wheel to insure it's not cracked when you
mount it.

I even tried to use a diamond point intended for the surface
grinder to make them concentric and it didn't seem to work very well.
I was holding it by hand.

As I said, there's nothing wrong with the concept, but it requires a light
touch to be effective. Assuming you still have the diamond at your
disposal, you might try again, making sure the nuts on the spindles are well
snugged. I failed to mention the possibility of your wheels moving about on
the arbor. You want the nuts tight, but not excessively. It's desirable
to learn to use a little less pressure when tightening fasteners on grinding
equipment. Unless something goes very wrong, there's usually not all that
much pressure involved in grinding.

How do I dress the wheels to make them round?

Hopefully something I've said will be useful. Why don't you give it a go,
then let us know.

Since the wheels are not round, they are difficult to use
for anything except rough grinding.

You don't have to say anything to convince me. I'm the first to say that a
grinding wheel that doesn't run true is worthless.

hope this is clearer?

I think so, although I'm really surprised that you aren't experiencing
success. Are the bearings good in the motor?

I hope you realize that what the problem could be might jump right out at
me, or others, but you may not recognize it, so you could have overlooked
something that might be important. That's why I asked for you to describe
what you're doing, and how you're going about doing it.

Harold

In article , Harold and Susan Vordos says...

If they have segmented pieces that spin, that's what they are. Jim likes
'em, and even ol' teenut used to extol their virtues, but I'll put my
grinding experience up against their opinions any time anyone wants to have
a discussion. As I said, there is no better way to prepare a wheel for
cutting. By their nature, they leave very sharp grain when properly applied.
Problem is, it's hard to get a wheel running true. In order for them to
function properly, they require a given load, otherwise all you do is grind
away the components. They dress by hammering the wheel, breaking it into
fine particles. Assuming you can get the wheel running dead true, you
can then bear down adequately for the dresser to do a good job, but you can
waste a lot of wheel getting there, and it's not all that hard to get the
wheel to start bouncing again while you're using it. As I said, I avoid
them totally. Don't even own one, nor do I care to. If I had a large 3
phase grinder for grinding on weldments, I'd likely have a different
attitude. They're great for that application.

Yep, that sounds like a star dresser to me.

I've never had a wheel that ran out, right from the box, so I can't
say how poorly they would true one. They are pretty good for getting
the wheel opened up again, and they're pretty good at getting a flat
surface once it gets grooved or marked.

I've tried the SiC dresser stick that you suggested. I may have
been using too hard a touch on it, given your comments above.

As I said, I've never had a wheel that did not serve for at least
reasonable grinding, right out of the box. What are the chances
that there's just something wrong with the wheel(s) he mounted?

Jim


--
==================================================
please reply to:
JRR(zero) at pkmfgvm4 (dot) vnet (dot) ibm (dot) com
==================================================

I've never had a wheel that ran out, right from the box, so I can't
say how poorly they would true one.

New wheels come with cheap plastic centers so its difficult to get
them mounted concentric in the first place. Might not be a problem
with small wheels but it doesn't take much on a 10 inch wheel to make
the whole grinder vibrate. I think that lead use to be the prefered
material for adapting the large hole in the grinding wheel to the
smaller grinder shaft. Should I replace the cheap plastic spacers
with something better?

I am using the standard flanges and blotters supplied with the wheels.
I did not tighten the wheels very hard because they ususally tighten
themselves up pretty tight. A 1.5HP motor accelerates pretty rapidly
and the 10 inch wheels have a lot of mass so I suspect the motor
tightened them up very tight by now.

I suspect I'm using too much pressure on the dressers and not the
light touch that harold recommends.

This grinder was purchased used and the original 10 inch wheels were
worn down to about 7 inchs. It ran fine with the old wheels.

Perhaps I should remove one wheel to reduce the vibration and dress
the remaining wheel. After I get it running smoothly I can then
add the second wheel and dress it.


chuck

"jim rozen" wrote in message
...
snip------
As I said, I've never had a wheel that did not serve for at least
reasonable grinding, right out of the box. What are the chances
that there's just something wrong with the wheel(s) he mounted?

Jim

I'd be the last person to discount the possibility, even with today's
relatively good quality control. Weird things have been known to happen,
soft sections, irregular thicknesses, none of which you'd expect. I've
experienced wheels that ran terribly when installed, but turned out fine by
simply dressing properly. One may have to go so far as to dress the sides
to remove unwanted variations.

Harold

"Charles A. Sherwood" wrote in message
...
snip------

New wheels come with cheap plastic centers so its difficult to get
them mounted concentric in the first place. Might not be a problem
with small wheels but it doesn't take much on a 10 inch wheel to make
the whole grinder vibrate. I think that lead use to be the prefered
material for adapting the large hole in the grinding wheel to the
smaller grinder shaft. Should I replace the cheap plastic spacers
with something better?

If you find the plastic permits the wheel to move about too much, that
wouldn't be a bad idea, but use good sense. There are issues with the
spacers that are critical, which explains why they're sloppy. They may not
work perfectly that way, but they're safe. If you make your spacers too
tight, and the bore of the wheel isn't at a perfect right angle to the wheel
face, it's possible to fracture the wheel when you tighten the nuts. The
snug fit would limit the wheel's ability to square with the flanges, which
it will do, either by cracking the wheel, or compressing what ever is in the
way.

I am using the standard flanges and blotters supplied with the wheels.
I did not tighten the wheels very hard because they ususally tighten
themselves up pretty tight. A 1.5HP motor accelerates pretty rapidly
and the 10 inch wheels have a lot of mass so I suspect the motor
tightened them up very tight by now.

On the outside chance that isn't happening, check how tightly they are
held. If the nut had crud in the threads, it's possible it's not turning
freely, so it feels tight but it isn't. Long shot, yes, but worth a look.
Be certain that the nut runs freely, all the way until it hits the flange,
otherwise you have no clue if you're tightening the wheel, or fighting the
dirty thread. Your flanges should be imprinting the blotters. If you
see signs of the wheel sliding about, with smudges on the blotters instead
of imprints, you're not tight enough. The blotter should appear clean, but
compressed.

I suspect I'm using too much pressure on the dressers and not the
light touch that harold recommends.

It has been my experience that once a wheel starts bouncing, it encourages
itself. Especially if you have no fixed reference, when you try to reduce
the runout, all you do is make the wheel smaller. If you think you can
simply hold the dresser of choice against the wheel and improve it, you'll
be disappointed endlessly. You have to work smart at reducing the runout,
which means to take it off a little at a time, such that the bounce of the
wheel isn't transmitted into the dressing device. A light touch usually
solves that riddle, along with taking a narrow approach. Don't use the flat
face of a dressing stick, but a corner instead, where the amount in contact
is minimized. Once you get a spot running true, you can usually move out
and improve the immediate areas. It's not rocket science, but it does
require a little thought. Surely you've already noticed how the bouncing
wheel sets up a pattern that tends to repeat. You have to break the cycle.

This grinder was purchased used and the original 10 inch wheels were
worn down to about 7 inchs. It ran fine with the old wheels.

Perhaps I should remove one wheel to reduce the vibration and dress
the remaining wheel. After I get it running smoothly I can then
add the second wheel and dress it.

Unless you ended up with some very poor quality wheels, there's no reason to
not expect new wheels to run smoothly once dressed. If that's what it
takes, then that's what you should do. Just be certain that all your
efforts are when the wheels are at operating speed, and don't discount the
possibility that the wheel sides may not be parallel. That would certainly
yield a heavy side, and would be corrected only by dressing the sides of the
wheel. I often dress the sides with a diamond, strictly for balance, right
down to the blotter. It often improves how a wheel runs.

Harold

[...]

Well. I made long, stringy chips and did some experimentation with
chip breaker grooves. Not much, though. A very light shallow groove
worked quite well for most of what I was doing, so I didn't bother going
any deeper. Once I have an better supply of tool steel I'll get a
little more adventurous with my grinding.
But a funny thing happened that'll let me try another strategy for
manufacturing my flywheel. Previously, I was considering simply
restarting the flywheel even though it would mean a hit to my grade.
And today some folks were in the shop filming students engaged in hot,
sweaty, unadulterated learning. At one point they asked me to swap
places with another guy since I was short and he was tall. OK, I leave
him with a simple command: don't move or cut anything; just look pretty.
Of course, since he was one of the guys who almost never shows up he
can't follow simple instructions; when I got back the hub was gone from
my wheel--he also took the whole 1/8" in a single pass. At 1500 RPM.
Cool! I get to restart it and try a better way of making it, I have
free reign to mock the annoying twit, and I'm on TV! But the downside
is that he savagely molested my carefully ground tool. (not the one I
described in the other post--this is another tool that was prescribed by
the teacher for this project. Looks like a grooving tool about 3/16"
wide) I ground the tool back about 1/8" to get the evil off then let the
teacher know I was starting over and it wasn't my fault.
To face the piece I found that going from front to back with my tool
(fancy one, with the rake angles and chip breaker stuff) didn't work too
well. Came out nasty and teary and looked like hell and got hot. But I
was smart (at least I thought I was smart) and rearranged my tooling.
Instead of the normal mounting, I had the tool parallel with the axis of
the lathe, ran the lathe backwards, and moved the cross feed from back
to front. So, from the bit's POV, it was moving from right to left
across the face of the part. Near-mirror finish and I could go a lot
faster. First time in this class I've turned something to size +/-0.000
and perfectly flat all across. Stayed cool, too. Yay!
Now I'm tempted to make the ass-end of that toolbit for left-to-right
cutting so I can use a similar setup without having to run the lathe
backwards--just in case I'm stuck with one that can't.
So far for the wheel I've faced my piece to length and drilled and
reamed a hole. Before the end of class I got part way through making a
mandrel to hold it. It was a piece of scrap someone else left that was
a disc with a tit poking out of the center on one side. I faced the
wheel flat and turned that tit to my final size + about 0.030" so I'll
be able to center it up next class. I still plan to drill, tap and
split the tit for an expander screw. If I wind up having to remove the
holder before I finish we have a four-jaw chuck on one lathe, so I can
recenter it. I probably need to learn how to do that anyway.
This is getting to be scarily fun--I was actually happy when I found
out I had to do the wheel again. Damnit, I wish I could fit a lathe in
my apartment.

--
B.B. --I am not a goat! thegoat4 at airmail dot net
http://web2.airmail.net/thegoat4/

In article ,
Harold and Susan Vordos wrote:

"Charles A. Sherwood" wrote in message
...

[ ... ]

I am using the standard flanges and blotters supplied with the wheels.
I did not tighten the wheels very hard because they ususally tighten
themselves up pretty tight. A 1.5HP motor accelerates pretty rapidly
and the 10 inch wheels have a lot of mass so I suspect the motor
tightened them up very tight by now.

On the outside chance that isn't happening, check how tightly they are
held.

The simple way to do this is to grip both wheels, and try
(without too much force) to advance one beyond the other, and then the
other way. Too much force, and you wind up actually loosening the nut
on whichever side is moving forwards, but light pressure should tell you
whether one is slipping.

If the nut had crud in the threads, it's possible it's not turning
freely, so it feels tight but it isn't. Long shot, yes, but worth a look.
Be certain that the nut runs freely, all the way until it hits the flange,
otherwise you have no clue if you're tightening the wheel, or fighting the
dirty thread. Your flanges should be imprinting the blotters. If you
see signs of the wheel sliding about, with smudges on the blotters instead
of imprints, you're not tight enough. The blotter should appear clean, but
compressed.

And also -- some flanges are rather poor shapes. Your machine
ran well with the older wheels, so this probably is not the problem, but
if it is, use your lathe to turn up a pair of flanges which are true on
both sides. Be sure to relieve the face except for perhaps 1/4" or so
at the outside diameter, which is where you want it to grip.

I suspect I'm using too much pressure on the dressers and not the
light touch that harold recommends.

It has been my experience that once a wheel starts bouncing, it encourages
itself. Especially if you have no fixed reference, when you try to reduce
the runout, all you do is make the wheel smaller. If you think you can
simply hold the dresser of choice against the wheel and improve it, you'll
be disappointed endlessly. You have to work smart at reducing the runout,
which means to take it off a little at a time, such that the bounce of the
wheel isn't transmitted into the dressing device. A light touch usually
solves that riddle, along with taking a narrow approach. Don't use the flat
face of a dressing stick, but a corner instead, where the amount in contact
is minimized. Once you get a spot running true, you can usually move out
and improve the immediate areas. It's not rocket science, but it does
require a little thought. Surely you've already noticed how the bouncing
wheel sets up a pattern that tends to repeat. You have to break the cycle.

What I've done to true a wheel is to put a stop sleeve on a
long-handled diamond dresser, (assuming that the tool rest has a clean
outer edge), and adjust so it just barely takes something off the wheel,
pass it back and forth until it stops spitting, then adjust it just a
little deeper and repeat, until you get a clean wheel the whole way
around. Repeat with the other wheel, and once both are balanced, you
can then use your dressing stone to open up the wheels which are too
smooth thanks to the diamond.

I've done this using parallel machinists' clamps, but I really
should take the time to make a collar on the lathe for the task. It
could even be a two-piece one which would let you make fine adjustments
as to depth once you started truing.

Hmm ... to be sure that you get it all -- perhaps you could roll
a well-inked stamp pad on the wheel's surface, and use that as a visual
indication as to when it is all removed?

This grinder was purchased used and the original 10 inch wheels were
worn down to about 7 inchs. It ran fine with the old wheels.

Then the flanges are probably good -- unless someone took time
to try different orientations for the flanges until they got the best
running?

Perhaps I should remove one wheel to reduce the vibration and dress
the remaining wheel. After I get it running smoothly I can then
add the second wheel and dress it.

Proably a good idea.

Unless you ended up with some very poor quality wheels, there's no reason to
not expect new wheels to run smoothly once dressed. If that's what it
takes, then that's what you should do. Just be certain that all your
efforts are when the wheels are at operating speed, and don't discount the
possibility that the wheel sides may not be parallel. That would certainly
yield a heavy side, and would be corrected only by dressing the sides of the
wheel. I often dress the sides with a diamond, strictly for balance, right
down to the blotter. It often improves how a wheel runs.

Another thing which can throw a wheel well off balance is if it
was soaking in water or oil at one side or the other. This should not
be the case with new wheels, but who knows what may have happened. If
this is the case, the balance will slowly change as they dry out.

Good Luck,
DoN.
--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

wheel. I often dress the sides with a diamond, strictly for balance, right
down to the blotter. It often improves how a wheel runs.

Not sure I could do that with the big CI guards installed. Removing the
guard would provide access to the outside, but still not sure about the
inside. One wheel does have a bit of runout side to side.

chuck

Damnit, I wish I could fit a lathe in my apartment.

You can. I started with a sherline and its about as portable as it gets.
The 7x10 and 7x12 import lathes are popular too.

chuck

"Charles A. Sherwood" wrote in message
...
snip--

One wheel does have a bit of runout side to side.

You'd have done yourself a service to have mentioned this early on. That's
a guarantee of vibration. There are ways to dress the wheel, including
turning it over to gain access to the opposite side if necessary. It's
unlikely you'll get the wheel to run smoothly as long as it is not parallel.

Before you do any dressing, locate the wheel such that the inside runs in
the best condition, so it may not need dressing. In a situation like this
I like the internal flange to be integral with the arbor, so it causes the
wheel to run true on one face. It makes correcting wheels much easier.

Get creative----with the side guard removed, use a piece of stock and a
clamp of sorts to build a temporary work guide along the side of the wheel,
adequate to support a diamond. Using a light touch, remove the highs from
the wheel side. If it improves the operation, it will become noticeable
as you dress, running smoother and smoother as you remove the thicker
portion of the wheel.

Harold