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Test Setup to determine if quill has excessive runout
Posted: Thu Jul 30, 2009 2:43 am
by JPG
Thought some of you might want to 'see' this!:D
[ATTACH]5389[/ATTACH]
Actually I was verifying alignment after grinding the shaft between the 'big' drill chuck and the 1/2" jacobs chuck.
I'm Mistyfied......
Posted: Thu Jul 30, 2009 12:50 pm
by etc92guy
..........and have never been a machinist.
I recognize the Jacobs chuck attached to the tailstock. It looks like you have a jawed drive on the quill. But what's the thing in the middle?

Posted: Thu Jul 30, 2009 1:05 pm
by mickyd
JPG40504 wrote:Thought some of you might want to 'see' this!:D
[ATTACH]5389[/ATTACH]
Actually I was verifying alignment after grinding the shaft between the 'big' drill chuck and the 1/2" jacobs chuck.
OK. This one definately needs more 'splaination. How is it checking for quill runout?
Posted: Thu Jul 30, 2009 8:09 pm
by JPG
etc92guy wrote:..........and have never been a machinist.
I recognize the Jacobs chuck attached to the tailstock. It looks like you have a jawed drive on the quill. But what's the thing in the middle?

That "thing" in the middle is a 1" Jacobs chuck. I ground down the tapered adapter to 1/2" so it fit into the 1/2" jacobs chuck(ss issue). This will allow me to chuck anything up to 1" od. Yes I used the ss to do the grinding and the quill to feed the 'workpiece' across the grinder.
Posted: Thu Jul 30, 2009 8:38 pm
by JPG
mickyd wrote:OK. This one definately needs more 'splaination. How is it checking for quill runout?
The tapered tail stock adapter is NOT forced into the tailstock. It turns freely and when pulled out slightly from the tailstock provides an ability to see any wobble.
The three jaw chuck(that humongeous hunk of steel on the left) centers onto the barrel (chuck key hole 'part') of the 1" chuck. This arrangement was used to move the shaft being ground(rotated and laterally fed).
To verify alignment(and possible quill runout/wobble) I attached the 1/2" chuck onto the newly ground shaft, inserted a tailstock arbor adapter into the 1/2" chuck 5/8" back bore.
By observing the path of the end of the tapered tailstock adapter as the whole thing is rotated by hand(end barely into the tailstock) the amount of wobble is determined. Surprisingly there is very little.
I am delighted with this outcome after attempting to grind the shaft down to 5/8" using the 1" chuck jaws. Sadly the jaws are funky and that attempt met with failure(too much eccentricity). Now I can turn my attention(grinding) to the jaws themselves. BTW new jaws cost over $150 a set and require a hefty press to disassemble and assemble the chuck. I do not have either the $$ or the press!
This is NOT a recommended setup for anything but an isolated use. All this weight on the quill is far more than the ss designers intended. The quill is reluctant to move in and out due to the force of all this weight. I first tried it with the original 45+ year old single bearing quill(WAY too much runout). I then installed a new two bearing quill which I had been putting off installing.
Also all this revolving @ 700 rpm is a bit "dangerous". EVERYTHING absolutely must be tightened with a passion! Fortunately everything here IS balanced!
Posted: Sat Aug 01, 2009 4:31 am
by mickyd
Can the quill runout also be checked directly with a
dial indicator?
Posted: Sat Aug 01, 2009 11:10 am
by JPG
mickyd wrote:Can the quill runout also be checked directly with a
dial indicator?
Of Course! [Assuming one HAS one!] [Assuming tailstock run-out was the real intent!] I was TRYING to be tongue in cheek!:D I was merely determining if my regrinding effort achieved acceptable results.
I did NOT expect 'perfection' with this crude setup! Just trying to get the shaft straight enough

to the chuck so it would run with 'minimal' wobble.
Posted: Sat Aug 01, 2009 1:36 pm
by mickyd
JPG40504 wrote:Thought some of you might want to 'see' this!:D
[ATTACH]5389[/ATTACH]
Actually I was verifying alignment after grinding the shaft between the 'big' drill chuck and the 1/2" jacobs chuck.
I just noticed the second sentence of your original post. I thought you WERE actually developing a runout setup, thus I planted the indicator seed (just in case you were stuck on the concept).
How about posting a photo of the 1" chuck with your grinding effort exposed. It looks like an interesting concept.
Did you recently acquire the 3 (or maybe 4) jaw chuck? If so, are you going to retire the expansion freeze plug you used to turn your tubes for polishing?
Posted: Sat Aug 01, 2009 3:33 pm
by JPG
mickyd wrote:I just noticed the second sentence of your original post. I thought you WERE actually developing a runout setup, thus I planted the indicator seed (just in case you were stuck on the concept).
In Spite of appearences, My name is NOT Rube Goldberg!:rolleyes:
How about posting a photo of the 1" chuck with your grinding effort exposed. It looks like an interesting concept.
Your wish - My command??
[ATTACH]5396[/ATTACH]
BTW The chuck KEY handle is 8" long! The shaft that was ground started life as a #5 Jacobs taper to a #3 Morse taper adapter(BADLY DAMAGED by a previous owner!).
Did you recently acquire the 3 (or maybe 4) jaw chuck? If so, are you going to retire the expansion freeze plug you used to turn your tubes for polishing?
Yes! 3 jaws. Courtesy of 'Betty....'! That is what HE used it for!
..........
Posted: Sat Aug 01, 2009 5:36 pm
by fjimp
In Spite of appearences, My name is NOT Rube Goldberg!
My someone, I am not quite certain is dating themselves. My kids and grand kids look at me as though I am from another planet when I use that line. fjimp