Ignoramus16551 wrote:

On 2011-06-15, Lloyd E. Sponenburgh lloydspinsidemindspring.com wrote:
Ignoramus10056 fired this volley in
:

It took about an hour, but I am finally done, trammed it with a dial
indicator. 0.001" over about 4 inches

Hardly done! G

That means it's off more than two tenths just over the diameter of a 1"
bit. That wouldn't give very pretty facing work.

But that's just my opinion.

This was the best that I could do.

I will try to face some piece of material and see how it looks with
the head trammed.

I do have a question, though: Since yours is a fixed ram machine,
how did you go about it? Did you follow the maintenance manuals, or
come up with your own technique? That's a heavy head, and when you
loosen the bolts, it wants to move all on its own.

There is a eccentric cam on one of the four bolts. This is what I
used.

I used one of those mills about 20 years ago. If I remember the feet
contact and adjustments on the floor also will affect how true the head
is.

You should be able to get it closer than .001" for a 4 inch sweep. You
should be able to face a piece of aluminum with a 4" flycutter without
any visible step showing between passes.

-jim




i

Bob La Londe wrote:

GeoLane at PTD dot NET wrote in message
...
On Wed, 15 Jun 2011 13:01:45 -0700, "Bob La Londe"
wrote:


I don't like that, because it relies on two separate indicators, and
that
introduces uncertainty as to their mutual adjustment an reading.

Nope. While its nice if they are the same its not necessary for them to
be.
You can make a home made one all wonky and have it work perfectly. Just
set
your manual zero indicator mark the same for both indicators at the same
spot on the table. They can be within the range of the indicator off from
each other and still work perfectly that way. It took me a while to get a
reflexive feel for relative vs absolute measurement, but once I did life
became a lot easier.

I have a piece of square aluminum bar stock with threaded holes all over
it
I use for all kinds of things now. I just bolt an indicator and a stud on
wherever I need them. Work on my lathe, any of the mills whatever.

How do you use your home mader? Do you set them to zero, then turn
the device 180º and move the head until it's half of the difference
from the original reading? Rinse & repeat until it's zero?

Set one to zero. Turn 180 set the other to zero. Turn back and adjust. I
crane my neck once. The way Jon does it is better, but I have not the
patience for that, and it would require craning my neck every which way to
read it.

I used to do it with one indicator on a bar and I did crane my neck around
to do it. With two its faster. My machines are not very rigid, and my high
speed spindles are just in aluminum clamp mounts so its all a compromise
anyway.

What's an SPI?



SPI = Swiss Precision Instruments, Inc.

On 2011-06-16, Bob La Londe wrote:
GeoLane at PTD dot NET wrote in message
...
On Wed, 15 Jun 2011 13:01:45 -0700, "Bob La Londe"
wrote:


I don't like that, because it relies on two separate indicators, and
that
introduces uncertainty as to their mutual adjustment an reading.

Nope. While its nice if they are the same its not necessary for them to
be.
You can make a home made one all wonky and have it work perfectly. Just
set
your manual zero indicator mark the same for both indicators at the same
spot on the table. They can be within the range of the indicator off from
each other and still work perfectly that way. It took me a while to get a
reflexive feel for relative vs absolute measurement, but once I did life
became a lot easier.

I have a piece of square aluminum bar stock with threaded holes all over
it
I use for all kinds of things now. I just bolt an indicator and a stud on
wherever I need them. Work on my lathe, any of the mills whatever.

How do you use your home mader? Do you set them to zero, then turn
the device 180? and move the head until it's half of the difference
from the original reading? Rinse & repeat until it's zero?

Set one to zero. Turn 180 set the other to zero.

Actually, to half of the difference.

Turn back and adjust. I
crane my neck once. The way Jon does it is better, but I have not the
patience for that, and it would require craning my neck every which way to
read it.

I used to do it with one indicator on a bar and I did crane my neck around
to do it. With two its faster. My machines are not very rigid, and my high
speed spindles are just in aluminum clamp mounts so its all a compromise
anyway.

What's an SPI?

"Pete C." fired this volley in news:4dfa2a54$0
:


I think that could introduce errors if the vice is not solidly locked
closed/down. The vise way surfaces with the vice open are probably
better since those are the surfaces your part or parallels supporting
your part reference off of generally.


I think that could introduce some errors beyond that.

Unless you're _positive_, Ig, that the plate itself has been ground flat
to within tenths, end-to-end, you have no way of telling if one end is
high, or there are bellies or waves in it.

You need to tram to the surface of the bed, which at least once was
ground to precision.

LLoyd

Ignoramus30422 fired this volley in
:

Actually, to half of the difference.

No, Ig. Not to start. You make both indicators read the _same_spot_ on
the bed, and zero them both to that one spot. THEN you start looking for
differences, but not until you've zeroed both indicators.

LLoyd

"Lloyd E. Sponenburgh" lloydspinsidemindspring.com wrote in message
. 3.70...
"Pete C." fired this volley in news:4dfa2a54$0
:


I think that could introduce errors if the vice is not solidly locked
closed/down. The vise way surfaces with the vice open are probably
better since those are the surfaces your part or parallels supporting
your part reference off of generally.


I think that could introduce some errors beyond that.

Unless you're _positive_, Ig, that the plate itself has been ground flat
to within tenths, end-to-end, you have no way of telling if one end is
high, or there are bellies or waves in it.

You need to tram to the surface of the bed, which at least once was
ground to precision.


Actually, you want to

(1 ) set a known flat surface ( a granite surface plate is typically used )
onto the table, and level it to be parallel to the X and Y TRAVELS using
shim stock or machinist jackscrews while moving the table left /right and
forward/reverse.

(2 ) THEN set a cylindrical square onto the surface plate and make sure that
your z travel is perpendicular to x and y....if it's not, then you need to
shim the collumn or scrape the knee ways before proceeding....

Otherwise, sweeping the spindle in a circle and ****ing around cocking the
head back and forth is basically a crap shoot when it comes to hoping to
obtain better finishes and higher 3 dimensional accuracy.

On 06/16/2011 12:23 AM, Ignoramus16551 wrote:

Jon, I wonder if a circle, milled on a moving table, represents a true
reference surface, or not. I used the top of the Kurt vise as a
reference surface.

Well, if the ways have wear, this is the only way to establish the true
"plane" of motion. Of course, it isn't actually a plane, but a surface
that is close to a plane.
It was not "really hard", like changing a transmission on a car on a
hot day, but after a while I hit a virtual wall and could not improve
beyond 0.001" over 4 inches swing.
If the object you are tramming to is truly planar, you should be able to
do better. But, if it is rocking on burrs on the table or not truly
flat, then it will be impossible to tram to it with any greater accuracy
than the flatness of it.

I can't get better than .001", maybe even worse, but when sweeping the
circle, then the deviation of the ways becomes quite clear. I set it so
that the +X and -X are equal, and the +Y and -Y are equal. But, there
are significant swings of the indicator, for instance from +X around to
-X, there is a rise in the middle, because the table moves in a slight
arc from one end to the other.

it won't get any better until I tear the machine down and scrape the ways.

Jon

On Thu, 16 Jun 2011 00:18:37 -0500, Ignoramus16551
wrote:

On 2011-06-15, Gunner Asch wrote:
On Wed, 15 Jun 2011 07:53:57 -0500, Ignoramus10056
wrote:

It took about an hour, but I am finally done, trammed it with a dial
indicator. 0.001" over about 4 inches. (diameter of the circle that
the indicator makes when attached to spindle).

i

Only .001?

Why did you bother? Thats pretty far out.

Mine is trammed at .0003 at 8" and its Almost ok

I could not get it better than that. Spent 10 minutes on that final
adjustment and nothing improved.

i

Then you may have to pull the head and open up the mounting holes a bit
more. Just a smigeon. Ive seen this on more than one miller..usually
Chicom..shrug but one Okuma as well

Gunner

--
Maxim 12: A soft answer turneth away wrath.
Once wrath is looking the other way, shoot it in the head.

On 2011-06-16, Gunner Asch wrote:
On Thu, 16 Jun 2011 00:18:37 -0500, Ignoramus16551
wrote:

On 2011-06-15, Gunner Asch wrote:
On Wed, 15 Jun 2011 07:53:57 -0500, Ignoramus10056
wrote:

It took about an hour, but I am finally done, trammed it with a dial
indicator. 0.001" over about 4 inches. (diameter of the circle that
the indicator makes when attached to spindle).

i

Only .001?

Why did you bother? Thats pretty far out.

Mine is trammed at .0003 at 8" and its Almost ok

I could not get it better than that. Spent 10 minutes on that final
adjustment and nothing improved.

i

Then you may have to pull the head and open up the mounting holes a bit
more. Just a smigeon. Ive seen this on more than one miller..usually
Chicom..shrug but one Okuma as well

I think that I am fine the way I am. I just milled an aluminum flat
with a 1/2" end mill, and can't feel any surface imperfections.

i

On Thu, 16 Jun 2011 07:49:16 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

Gunner Asch fired this volley in
:

Damn..and he actually paid for that?

It's a CNC, Gunny. Lacking a 4th or 5th axis, all it can do is 2.5D. It
can hardly be called a manual machine, although his EMC work allows
joysticking.

Unless a CNC has head gimbaling under control, the ability to tilt the head
isn't of much use.

LLoyd


Ah! Id forgotten he was using a Bridgeport (?) Series 3 or something.

Yah..he really really needs to get it down to small tenths else its
really going to show up on facing and whatnot.

I think Id check parallel front to back first..see if the table has
sagged..in which case...perhaps tightening up the Z axis table gibs may
help a lot.

And then go x axis side to side



Gunner

--
Maxim 12: A soft answer turneth away wrath.
Once wrath is looking the other way, shoot it in the head.

On Thu, 16 Jun 2011 08:26:07 -0500, "Pete C."
wrote:


Larry Jaques wrote:

On Thu, 16 Jun 2011 00:20:06 -0500, Ignoramus16551
wrote:

On 2011-06-15, Karl Townsend wrote:
On Wed, 15 Jun 2011 08:02:36 -0700, Gunner Asch
wrote:

On Wed, 15 Jun 2011 07:53:57 -0500, Ignoramus10056
wrote:

It took about an hour, but I am finally done, trammed it with a dial
indicator. 0.001" over about 4 inches. (diameter of the circle that
the indicator makes when attached to spindle).

i

Only .001?

Why did you bother? Thats pretty far out.

Mine is trammed at .0003 at 8" and its Almost ok


Shrug

Gunner

You should let Iggy know getting it this close is ten times the work
of getting within .001 over 4 inches.

I fiddled with my Large Super Max till it was --O--O-- (that's an
arrow through two balls, or "dead nuts", an official engineering term)
and then drilled and installed a taper pin to keep it there.

I will try using the mill, trammed as it is. This is a "many times"
improvement over what I had when it was untrammed.

Are you sweeping a tiltable head to zero, Ig? When I hear the term
"Tramming", I think zeroing the table to the head.

(Just clarifying my newbieness, too. What's the terminology, guys? It
wasn't covered in Briney's _The Home Machinist's Handbook_)

It's not a tiltable head as in a normal use axis like a regular
Bridgeport. It's a CNC with a fixed head, but that still needs to be
fine tuned to ensure its square to the table and as Iggy noted, it has
some eccentric cams in the head mount to allow that small amount of
adjustment.


And if its off, front to back...it may need some shims. Which is not all
that uncommon.

Gunner

--
Maxim 12: A soft answer turneth away wrath.
Once wrath is looking the other way, shoot it in the head.

On Thu, 16 Jun 2011 10:14:11 -0500, Ignoramus30422
wrote:

Pete, what do you think about using the top of a Kurt vise as a
reference surface?

No!

Gunner

--
Maxim 12: A soft answer turneth away wrath.
Once wrath is looking the other way, shoot it in the head.

On Thu, 16 Jun 2011 20:01:20 -0500, Ignoramus30422
wrote:

On 2011-06-16, Gunner Asch wrote:
On Thu, 16 Jun 2011 00:18:37 -0500, Ignoramus16551
wrote:

On 2011-06-15, Gunner Asch wrote:
On Wed, 15 Jun 2011 07:53:57 -0500, Ignoramus10056
wrote:

It took about an hour, but I am finally done, trammed it with a dial
indicator. 0.001" over about 4 inches. (diameter of the circle that
the indicator makes when attached to spindle).

i

Only .001?

Why did you bother? Thats pretty far out.

Mine is trammed at .0003 at 8" and its Almost ok

I could not get it better than that. Spent 10 minutes on that final
adjustment and nothing improved.

i

Then you may have to pull the head and open up the mounting holes a bit
more. Just a smigeon. Ive seen this on more than one miller..usually
Chicom..shrug but one Okuma as well

I think that I am fine the way I am. I just milled an aluminum flat
with a 1/2" end mill, and can't feel any surface imperfections.

i

You may not see any surface imperfections..but when you cut a
groove..will it be square and perp...or will it lean in one direction or
another?

If that groove you cut is .003 off...the matching part... say..10"
long..will be off .030 at minimum from verticle.

Shrug. Do as you wish.

Gunner

--
Maxim 12: A soft answer turneth away wrath.
Once wrath is looking the other way, shoot it in the head.

Gunner Asch on Thu, 16 Jun 2011 18:55:37 -0700
typed in rec.crafts.metalworking the following:
On Thu, 16 Jun 2011 10:14:11 -0500, Ignoramus30422
wrote:

Pete, what do you think about using the top of a Kurt vise as a
reference surface?

No!

You don't think it better than using Kurt's face as a vice? [s/fx:
rimshot!]

pyotr

I'll just go quietly ....
--
pyotr filipivich
We will drink no whiskey before its nine.
It's eight fifty eight. Close enough!

On 06/16/2011 10:14 AM, Ignoramus30422 wrote:

Pete, what do you think about using the top of a Kurt vise as a
reference surface?

Completely useless. There is no reason the top of the movable vise will
be really parallel to anything in particular. Since it is a Kurt, it
won't be real far off, but a few burrs on the table or bottom of
the vise, on the bed of the vise, under the movable jaw, etc. will add
up to it not being real parallel at all. Just put the dial indicator on
the top of the vise and run the table around to see how far off it is.

Jion