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TR
12-12-2010, 07:42 AM
I notice when I fit my chuck there is a slight gap between the back of the chuck and the face of the spindle. The front part of the spindle has a slight taper which I suppose is to provide a taper type lock and then using the cam locks, pull the chuck in tight over the taper. Is this correct ? Or should the chuck fit flush on the spindle's face ?

I'm still trying to solve the chuck runout problem, I think the chuck is not fitting correctly on the spindle mount.

http://i663.photobucket.com/albums/uu354/topari/DSCN0557_998Medium.jpg

Davo J
12-12-2010, 07:53 AM
It should fit on the taper firm and take a tap with a rubber mallet to remove, but should pull up against the spindle.

Dave
EDIT
Just to add that I picked up a spare 3 jaw a couple of years ago and it was a tight fit and wouldn't pull up, so I mounted the 3 jaw in a 4 jaw backwards and machined the taper out a little. Doing it this way I could turn the whole lot around to try it on the spindle then machine a little more as needed until I got a good fit.

Ian B
12-12-2010, 09:40 AM
Do you have (or have access to) something else on a D1-4 mounting? If so, try fitting it - as davo says, the flat faces should pull up and make contact. This will give a clue as to whether it's the spindle or backplate that are not within tolerance.

Having a gap between the faces will play havoc with the chuck's alignment, and will be seen by taking runout readings close to the chuck, and then further towards the tailstock; the further from the chuck, the greater the runout.

Ian

Mcgyver
12-12-2010, 10:21 AM
[QUOTE=TR]

I'm still trying to solve the chuck runout problem, I think the chuck is not fitting correctly on the spindle mount.

[QUOTE]

sounds like you've found your problem....now your problem is figuring out if it is the lathe or chuck that is incorrect. Lets hope its the chuck!

The taper locates things, its not really a lock, but it as to be just so such that the chuck back is in full contact with it and the face of the spindle. Right now I'd bet one of the pins pulling it into contact making it off kilter like swash plate. If you need further proof that this is your problem indicate your test bar and see how wildly the readings change as you move away from the chuck

Its a difficult thing to measure, where a cone meets a plane, and tricky to machine. I'd start by checking everything else you've got that fits. If nothing fits well, probably the lathe, if everything does, probably the chuck. Check fit with feeler gauges and with with an indicator - see if you can move the chuck side to side (checks if its engaged in on the taper). Some blue is also a good way to check.

rohart
12-12-2010, 10:22 AM
Since I've just got a machine with D1-3 camlock spindle, this is something I've been thinking about.

I tend to agree that to leave everything to the taper, ie having a significant, say > 5 thou, gap between the faces, would allow uneven tightening of the cams to leave the chuck pointing off-centre.

But where do you stop ? If the faces butt up properly, and the taper has a gap, you've got no centring.

So ideally you'd like the clamping pressure shared between the taper, to get centring, and the faces, to get direction.

Right. Well, that's a pretty fine tolerance if you ask me. So you've got to decide which side to err on, and I'd prefer to err on leaving a gap.

Let's look at it another way. Suppose you leave a gap, and you tighten the cams harder. The taper clamps up harder and the gap gets smaller. So everything gets better.

Now suppose there's no gap, and the taper is loose. Tighten it harder, and the taper will stay just as loose as before. All you'll do is make the lack of centring more definite.

So, I'd rather have a very small gap, that tended to disappear as I tighten the cams a little too tight.

Davo J
12-12-2010, 10:43 AM
If it only needs a small amount use a piece of emery while it's mounted backward like I said above instead of machining. Somewhere on this forum someone posted how much off the taper would move it closer to the spindle face (X) amount. I know it's not much and when I machined it, I over shot and then had to face off a bit to get it back again. I then finished it off with emery.
I wouldn't touch the spindle and you will find it's hardened. All my chucks/back plates get pulled up with the cams and then it takes a swift blow from behind with a rubber hammer to unseat it off the taper and I have no repeatability problems.

Dave

DeereGuy
12-12-2010, 11:21 AM
The taper at the end nearest the spindle face should measure 2.50050 +0.0005. The specs are very clear on this. Here is a link to what things should be mearsuring out to....
http://shopswarf.orconhosting.net.nz/chuckmt.html

I have been making D1-4 Rotary table adapters for the D1-4 and I have made everyone to these measurements....all work perfectly.

If it is the spindle I would go back to the seller and have them replace your lathe....

Forrest Addy
12-12-2010, 11:39 AM
The D1 and A1 spindle nose series standards provides a little "draw" where the female taper is a trifle smaller than the male taper. The gage line dimensions of the tapers specifed in the standard show this interferance but I can't recall exactly what it is.

If the chuck is mounted and held engaged but not clamped you should be able to get a 0.001" or 0.002" feeler in the gap. When the camlocks are drawn up to be fully tensioned, the taper engages, elastically deforms a trifle in acommodation, and the back face mates solidly. It's a very accurate, repeatable system if kept scrupulouly clean during tooling changes.

Mcgyver
12-12-2010, 12:46 PM
[FONT=Arial][SIZE=3]The taper at the end nearest the spindle face should measure 2.50050 +0.0005. The specs are very clear on this. Here is a link to what things should be mearsuring out to...

clear on paper, difficult to measure or to do. Most spindles will have a relief there, or should, so the intersection of cone and face is a theoretical place not actual. Even if it were actual, any radius on the tool or grinding wheel that cut it will wreck the measurement....and what measurement tool do you get in there that is reliable to 1/2 a thou?

When I've done it I've used a female i trust (not many of those lol), turned the taper first, then start kissing off thou's on face using feeler gauges to know how much to take off. I didn't know until Forrest's post that it was supposed to be a thou but that's probably where it ended up.

Forrest Addy
12-12-2010, 01:35 PM
McGyver

Gage lines have to be measured on the male taper. You can't actually measure the gage line axial location of a flanged gage. You have to calculate the offset and tangency of pins from the gage line (intersection diameter) and measure over the pins. It's a real worm rassle to set up and measure ensuring the pins are shouldered and parallel to each other but it can be done. As you say, tapers are best gaged and the gage should incorporate features facilitating their calibration. The same thing can be done on a CMM without a whole lot of fuss and feathers. Damn new fangled gadgets anyway.

As a matter of fact I designed a set of A11 gages for a Landis roll grinder headstock. I made the gages to match faces with the tapers having zero radial play. The female product taper was gaged by recording radial movement of the male gage assembled on the part. I could not for the life of me think of a better way to do it and still have the gages self check each other's taper - the male gage being the only one measureable outside of a metrology lab.

sch
12-12-2010, 01:36 PM
It would be helpful if the OP indicated how much runout he is
getting. As Forest has posted in the past 3J chuck runouts
of less than 6 thou or so are excellent and par. I have found
with my D1-4 that it makes a difference which post on the
chuck goes in which hole, it also helps to torque the cams
in the right direction (early in my experience I could not keep
track CW or CCW to turn the cams). Try all three holes,
rotating the chuck 120D, and lightly mark the spindle to index
it first and see if you get better indexing at one hole. The
amount of torque placed on the cams can influence runout as
well. Not to go into cam pin positioning, dings, debris etc.
Determining if the spindle is off is a high art as you are measuring
in the sub thou range.

Rich Carlstedt
12-12-2010, 05:07 PM
At the risk of being a party spoiler here, I have to say I disagree with many of the comments made in this thread. Let me explain and please approach this with out pre-concieved ideas

In any tooling or production setup, you can only have ONE boss per axis. This is the cardinal rule for jig and fixture design.
You can see this easily with the common knowledge that 2 points make a straight line. So when you make a fixture , you use two points to hold a part that you want straight/parrallel to your desired position. you don't use 3 or 4.
For a "plane" you would need 3 points, because we know that 3 points that are not collinear (not in allignment) make a plane
Why am I saying this ?
Because you cannot have a taper and a plane function for the same purpose !
They are in direct conflict with each other
Do you know of any tapered collet that that has a stop ?
Now look at the design for a D1-5 taper
Note the VERY specific Taper (7 Deg 7.5 min = 3"/Ft combined ang)and Specific Diameter 2.5005.
The Tolerance is +.0005, thats it !
Note the the spindle nose flat is not a dimensioned distance from the sharp line of the taper. Note also that the face to the pilot nose is a fraction ( 7/16 in the real specs)
Why would this be critical if the specification is a fraction ?
What this means is that there is no concern by the machine tool industry for the "space" that some here are concerned over.
When the chuck is drawn up evenly on the pins, the chuck will be proud, of the face. I have seen this in most all the shops I have been associated with and the pins visible as well.
As mentioned earlier, there is one boss, and it is the taper , as it is the only critically diimension component.
Pulling flush to the face is nice, but not specified, which means it cannot always be expected
Rich

philbur
12-12-2010, 05:25 PM
I guess you haven't heard of HSK toolholders.

Phil:)


In any tooling or production setup, you can only have ONE boss per axis. This is the cardinal rule for jig and fixture design.
Rich

DeereGuy
12-12-2010, 06:55 PM
clear on paper, difficult to measure or to do. Most spindles will have a relief there, or should, so the intersection of cone and face is a theoretical place not actual. Even if it were actual, any radius on the tool or grinding wheel that cut it will wreck the measurement....and what measurement tool do you get in there that is reliable to 1/2 a thou?

When I've done it I've used a female i trust (not many of those lol), turned the taper first, then start kissing off thou's on face using feeler gauges to know how much to take off. I didn't know until Forrest's post that it was supposed to be a thou but that's probably where it ended up.

Ok, good point, the taper on the adapters I have been making for the rotary tables go back to the face. The taper in the pic that the OP posted looks to me like it goes beyond the chuck face and the relief is cut outside of this. I could be wrong and these old tired eyes are getting worse than I thought.

In retrospec 2.5005 is what I shoot for but I use my 8" Bison chuck for the test fit and carefully take off .001 at a time until it does have just about a .001 proud of the face. The pins then pull it tight to the face of the adapter.

If the OP is talking about this kind of a fit then I don't think there is a problem with the taper.

Rich Carlstedt
12-12-2010, 07:34 PM
Phil, I think our discussions have focused on rigid tool systems.
While HSK is a supreme toolholder, it is designed to rely on the flange for support and the tapers (very thin wall) are designed to " flex" until the flanges interface. The extreme precision of these holders make them unique compared to all other systems

I quote a popular discription for those unfamiliar with HSK

"As the collet segments engage, the pullback force causes the shank to deform slightly, pulling the shank further into the receiver until contact is made between the flange and the receiver's face. The fact that the two tapers are in intimate contact due to the elastic deformation of the shank ensures the positioning accuracy and repeatability of the joint, both radially and axially, to 0.0001".

http://www.hskworld.com/articles/hsk_secrets/hsk_secrets.htm

The HSK components are designed and ground to have a .00025 "( .006mm) clearance flange to flange when the flexible tapers (non-solid) engage, then added force is used to flex the taper and bring the flanges together.
In this case, the boss is the flange as further loading produces no change.

A D1-4 taper spindle, or chuck is not designed to flex, but considered a rigid tool system
Thanks for bringing it up.
Rich

Mcgyver
12-12-2010, 07:43 PM
Forrest, mine was a simpler make one to fit another but i see what you're saying....having two pins, each in contact with both face and cone would allow you to measure across them and the critical dimension can be calculated. Well, now i know how to approach regrinding the lathe spindle if necessary :D

TriHonu
12-12-2010, 08:57 PM
Well this question has been asked many times on a number of forums.

Rather than to state my opinion, I will refer to two documents.

The manual for the Jacobs Spindle Nose Collet Chuck states "Place chuck in position on spindle and be certain that you can fit no more than a .004" feeler gauge between the front face of the spindle and the back face of the chuck." They do not want the chuck to fully seat. The mounting instructions want you to tighten the cams while indicating the collet taper to within .0001 inch TIR to allow for high precision centering.

Compare this with the mounting instructions for Rohm lathe chucks. They state to mount the chuck and without tightening the cams there should be a gap of .0008 - .002 inch. The manual states to evenly tighten the cams. The manual then states "Both the short taper and the face of the chuck must be in full contact with the spindle nose after mounting."


With the stated tolerance of the mount allowing +.0005 on the spindle, if you mount a perfect backing plate the math shows you will have a .002 inch gap between the back plate and face of the spindle.

However if your spindle is +.0005 and the back plate is also with in tolerance of -.0005 you will have a .004 inch gap before you tighten the cams. While a .002 inch gap can be closed with normal torque of the cams, you won't be able to close a .004 inch gap.

While high end lathes and back plates will fit up tight allowing for very quick and highly repeatable mounting, you will also find spindles and back plates that are with in tolerance that will have a gap after tightening the cams.

You can either live with having to indicate in the chuck each time you want to get it to run very accurate or you can start the process of determining whether your spindle taper, back plate taper or both are out of tolerance and deciding whether you have the skills or money to get the fit you desire.

I have the opposite problem. My D1-3 spindle is ground undersize. So I have to face or mill the back plates so the two tapers will register...:(

rklopp
12-12-2010, 09:44 PM
Somebody shoot me. A gap at the face is insane, both for accuracy and safety reasons. The whole point of the camlock system is fast, accurate chuck changes. If you had to tweak the cams and indicate a mandrel every time you changed a chuck, you'd pitch it all and go back to a threaded spindle. I can't imagine trying to tweak six cams - good grief! The reason a gap is unsafe is that it subjects the pins to the entirety of the cyclic stress, just like the case of an under-tensioned bolt in which the bolted joint separates. If the gap is closed, a significant fraction of the cyclic stress is shared with the chuck body and spindle nose, greatly enhancing the fatigue resistance of the assembly.

Jacobs does want the gap to close. You can pull a 0.004" gap shut with the cams. I do it all the time with my 2J Sjogren D1-3, which happens to have a sizeable gap when loose. Sure, you can indicate a collet chuck to get better runout, and tweak the cams a little and bump the chuck with a soft mallet, but it should all happen with the gap closed.

Mcgyver
12-13-2010, 12:25 AM
The manual for the Jacobs Spindle Nose Collet Chuck states "Place chuck in position on spindle and be certain that you can fit no more than a .004" feeler gauge between the front face of the spindle and the back face of the chuck." They do not want the chuck to fully seat. The mounting instructions want you to tighten the cams while indicating the collet taper to within .0001 inch TIR to allow for high precision centering.

I don't know that you can infer they don't want the chuck to fully seat from those instructions. they say no more than 4 thou before you've even turned a cam.....Maybe the reason for this instruction is that if the mount is supposed to be a slight interference as Forrest suggest, that technique pulls things snug compensating for any small high spot?

http://www.neme-s.org/images/Jacobs_Collet_Chuck/Jacobs_Rubber_Collet_Chuck.pdf


Compare this with the mounting instructions for Rohm lathe chucks. They state to mount the chuck and without tightening the cams there should be a gap of .0008 - .002 inch. The manual states to evenly tighten the cams. The manual then states [B]"Both the short taper and the face of the chuck must be in full contact with the spindle nose after mounting."

my world coincides with Rohms view, both surfaces need to be firmly in contact. The D taper section is so short I can't see it by itself register and hold tooling properly - that if the faces fail to mate, unless you indicated it each time I would suspect that it would end up as a swash plate, with part of the face mating and part not - the taper is the concentric reference but is too short to reliably hold the chuck in proper axial alignment .

I'm surprised that guys report it the norm for chucks to be some distance from the spindle and that the pins are visible. They've probably seen more lathes than I, but still, its not something i ever remember seeing. I went out and double checked my three and there is no chance of getting a feeler gauge in and no light visible so I believe the faces are firmly in contact as I believe they should be. Frankly it would seem a very un-sturdy mount if it wasn't in contact.

macona
12-13-2010, 12:48 AM
I have the opposite problem. My D1-3 spindle is ground undersize. So I have to face or mill the back plates so the two tapers will register...:(

I ended up regrinding the taper and back face on my 10EE. Used a CBN cup wheel on a tool post grinder. I set the taper angle to the compound using an indicator and then ground them. But when you grind down the outer taper you need to grind the face back to make sure the taper mounts to the chuck. Its delicate work. Removing fractions of a thou to get it right.

Forrest Addy
12-13-2010, 01:59 AM
You guys voting for face gap or no gap are missing the point. The A1 and D1 spindle nose taper series is a standard not subject to field revision by stated opinion or exception. Technical changes can be made but the process is exhaustive. Changes are intiated when the comment and suggestion sheet in the back of the standard document is filled out and submitted. The submttal is reviewed by the standards board. From there changes are made only after vetting and comments solicited in a process as stringent as when the standard was originally promulgated.

I think the face fit-up gap as specified in the A1 and D1 spindle nose series standard is a superb design. Radial clearance on the taper defeats the intent of the spindle nose standard. The standard as written and implemented ensures 0.0001" or better radial and axial registration repeatability of chucks and other workholding tooling resultng in a mechanical connection nearly as rigid as an equivalent mass of solid metal. Thus they can be interchangeably installed on lathe spindles made to the same standard - a portion is shown here in PDF:

http://www.cushmanindustries.com/catalogs/spindle-nomenclature.pdf.

I think this is the correct standard: ANSI Standard B5.9-1967 (reaffirmed 1972) if anyone wants to look it up.

Richard-TX
12-13-2010, 10:12 AM
I bought an import chuck that would not mate up completely. The taper portion of the D1-4 adapter plate was just about .0014 too small. I spent some time fixing that. The next import chuck I bought was from Shars. It fit correctly.

mayfieldtm
12-13-2010, 10:22 AM
I had the same problem.
I could not bring myself to grind on any tapers, so I milled out a stack of shims tightly pressed between two 1/4 pieces of aluminum.
These fit between the face and chuck back (of course).
I had a few each of 0.0005, 0.001, 0.002 and a 0.004" thick.
Playing with various configurations I found just the rite combination (0.0025").
Been very happy with the results.
( The 4 jaw doesn't need any. )

Tom M.

Richard-TX
12-13-2010, 10:35 AM
Grind? Why grind? I see no reason to grind when the factory that makes this stuff does not grind the chuck mounting plates.

If you go too far with the cut of the tapered portion, just take a little off the face.

rklopp
12-13-2010, 12:58 PM
There is a tolerance on the taper angle built into the standard. The male gauge has diameter-over-pins dimensions for 0.250-in pins located flush with the inner and outer faces of the taper. The tolerances are +/-0.0001". The female gauge taper is to be a "good Prussian blue fit" on the male gauge taper, so it picks up the taper angle tolerance. When fitting the female gauge to a spindle, there is a tolerance on the gap of 0.000" to 0.002" for D1-4. When fitting the male gauge to a chuck or whatever, there is the same +0.002" tolerance on the gap. The male gauge corresponds to the smallest allowable spindle taper. Thus, the minimum allowable gap before tightening the cams is 0.000" and the biggest gap is 0.004", for in-tolerance D1-4 assemblies. In no case is there allowed looseness in the taper fit. The gauges are applied with hand force. There are no provisions for forcing the gauges onto the taper using the cams.

Rich Carlstedt
12-13-2010, 10:34 PM
When you pay one company $200 for a back plate you expect quality
When you pay another company $42 for a back plate you "hope" for quality

The 42 dollar guy is counting on your comment tiffie

Rich

This whole discussion shows why the L Series (ie Lo, Loo) are the finest spindle noses you can have.... in my opinion.
Forrest, you are correct with the ANSI Standard B5.9-1967 .
They added the DI-3 andDI-4 specs at that time

Forrest Addy
12-14-2010, 12:01 AM
I have a vague recollection of some engineering analyst guy worked out the merits of the A1-D1 series spindle noses Vs the L-x series. Six of one half dozen of the other using gage line dia as a comparison feature for stiffness providing the supporting bearing fit is larger than the gage line dia.

However what stuck in my mind is repeat positioning accuracy. Radially, both A1 - D1 and L-x series spindle noses are about the same. The L-x series is axially variable because the taper draws more or less with collar torque, whereas, the A1-D1 series draws up and stops when the flange face mates. The difference is 0.001" or so and 0.0001" or less but them numbers are important only to some people.

Adding, some people suggest a "torgue sequence" of the cam-locks A`11 - D1 spindle nose to securing repeatable mounting of their lathe spindle tooling. I submit if the fit-up is clean and blemishes are stoned flush it should make no difference which cam-lock is snugged.

And for the record, if Old Tiffie wants to run radial clearance in the taper of his cam-lock equipped lathe that's his privilege. Anyone buying his stuff later should keep his mods in mind. It's a simple matter to face back the spindle nose flat and correct it to incorporate the right amount of draw.

PSD KEN
12-14-2010, 12:48 AM
My 14X40 seems to have a slightly large taper.
With 3 chucks ( 4 - 6 - 8") & collect chuck, after snugging #1 a bit I have to indicate the chuck, tweaking each came a smidgen slightly.
With a Bison I end up with .001.

Grinding this, that or the other 0.0001 is beyond my capability.

I seldom change chucks so I can live with it.

TR
12-15-2010, 06:50 PM
The manufacture says the chuck should fit flush against the spindle face. I have a 0.004" gap near number 1 jaw. No gap near the 2 and 3. Maybe I should use a breaker bar to try and tighten it just a bit ?

DeereGuy
12-15-2010, 07:54 PM
I have measured. < 0.01mm or very close to zero.

TR, are all the pins on the back of the chuck screwed in the same length?

Mcgyver
12-15-2010, 08:15 PM
The manufacture says the chuck should fit flush against the spindle face. I have a 0.004" gap near number 1 jaw. No gap near the 2 and 3. Maybe I should use a breaker bar to try and tighten it just a bit ?

:eek: this is not a problem brute force will solve

presumably the pin 1 is engaging with the cam, ie like deere guy says, the pin is the right distance out so the cam catches it?

Like I said earlier, that is your problem, its mounting like a swash plate. As earlier suggest you need to now determine if its the lathe spindle or chuck that is at fault - first thing is to try mounting any other tooling you have and check it with the feeler gauge....if everything else mounts ok dollars to donuts its the chuck

TR
12-15-2010, 08:32 PM
TR, are all the pins on the back of the chuck screwed in the same length?

yes, I even tried pins from my other chucks.

TR
12-16-2010, 07:11 AM
Good news. I used a breaker bar to close the .004" gap and now have TIR less than 0.03mm. Pretty good. Pretty tight fit.
I purchased some spare d1-4 cams just in case. The supplier told me they keep lots in stock because of demand. Typically machinists use a breaker bar to close gaps between the chuck and spindle face and sometime the cams break. Hard to believe.

Thanks for all the good advice.

Ian B
12-16-2010, 07:59 AM
Sounds like it's on the taper pretty tightly.

Have you tried to remove it yet?

Ian

TR
12-16-2010, 08:05 AM
Sounds like it's on the taper pretty tightly.

Have you tried to remove it yet?

Ian

Yes. The force I used on the breaker was not too big. It was just easier. Yes, tight fit. One whack of the rubber mallet and the chuck was loose.

rkepler
12-16-2010, 10:46 AM
Yes. The force I used on the breaker was not too big. It was just easier. Yes, tight fit. One whack of the rubber mallet and the chuck was loose.

One thing that I've found to help is that you make one pass just nipping the cams up, then a second pass tightening them to the final torque. Pulling the backplate in evenly helps a lot on the level of torque needed.

DeereGuy
12-16-2010, 12:44 PM
I know this will probably sound like overkill to most of you and certainly way to slow for the production guys....
I always....tighen mine just snugging by hand then I actually use a torque wrench and work my way around taking them to 50 ft lbs....Don't remember where I got that figure at...I know it was after I had shoulder surgery and was recovering.

In addition to the above...when I do get a new chuck I always try all the positions and note the best runout..then make a mark on the chuck so I always index it to the mark I have on the spindle.

Rich Carlstedt
12-16-2010, 06:38 PM
FACT CHECK TIME

Having read all the posts, I decided to do a little leg work, and it was rather interesting. I had a machine shop Seminar at a tech college 60 miles way and they have a lot of lathes with DI Spindles. So I asked the instructor for a .001 piece of shim stock. He only had a .0015 so I used it on the 8 lathes.
I found that on 6 of them, I could not insert the shim, or see light.
On one, there was a .002 clearance and the other was cocked, at maybe .004".
Turns out the .002 would not snug tight, but was also not "registered".
That means the O--O marks between the chuck and the spindle were not alligned. You always mount a DI with these marks. When the instructor released the chuck and reset it with the marks, it came in to .000" , but he did put a heavy twist on the wrench.
The last chuck was....loose on one pin ...and also not alligned
But guess what ? Not all chucks AND not all spindles had registration marks !
(3 spindles and 2 chucks were void on this)
So maybe if your chuck is not pulled against the spindle sufficiently, you have a problem wirh the "connection"

Moral of the story is that attention on these issues are important to note and do occur and should be addressed. I know the instructor (friend of mine) is greatful that I brought up the subject,
It may have prevented damage or injury .

Thank You Home Shop Machinist for the opportunity to promote shop safety !
Thank You also to Mr Forrest Addy..your proof was in the pudding !

Merry Christmas all
Rich