A small chuck and a part a little too big....

dtsh

H-M Supporter - Sustaining Member
H-M Platinum Supporter
Joined
Sep 22, 2017
Messages
136
What to do when the part *almost* fits into the chuck, but not quite? The correct answer is not "attempt to chuck it up with just the last few teeth gripping the scroll"

I've been putting off getting a larger chuck, mostly because I don't use the lathe nearly as much as the mill. I was attempting to hold a piece that was bigger than the little 4" chuck can realistically hold and as a result I evidently put too much stress on jaw 3 and broke off the first tooth.

I present for your entertainment, a chuck which had survived 100 years of use only to get broken by a noob.
It's a 4" 3 jaw Oneida National Chuck. I'm not certain as to it's age, it may or may not have been original to the 1903 Seneca Falls lathe, I don't know.

oneida_4_3jaw-1.jpg

Here's the damaged jaw, with the fragment in the center.
oneida_4_3jaw-2.jpg

I had to disassemble the chuck to get the fragment out.
oneida_4_3jaw-3.jpg

I have been putting off getting a larger chuck, I'm leaning toward an 8", but I'm uncertain if that might be a bit too much for a 9+" belt driven lathe. Have any suggestions?
 

benmychree

John York
H-M Supporter Gold Member
Joined
Jun 7, 2013
Messages
3,981
I doubt that a chuck with removable(reversible) top jaws was all that old. I have seen several chucks that were damaged in that same way.
 

catsparadise

Registered
Registered
Joined
Nov 21, 2015
Messages
48
That would explain how my 6" 3-jaw came to be the way it is. As part of the renovation of my lathe I stripped down the chucks to clean out the old goo and chips. When I came to re-install the chuck jaws I fitted jaw #1, then #2 & #3 and wound them into the middle to check they were correctly timed - which they weren't! Repeated twice* before checking everything and finding #1 has a tooth broken off, so it goes in too far. Re-installed in the order #2, #3, #1 and success.

The chuck works fine, but I only use it for hex stock or for diameters <0.5". I prefer the accuracy of the 4 jaw. (My 4-jaw is an 8" on a 13" swing lathe, so I think a 6" would be a better match for a 9" lathe otherwise you won't be able to use the chuck to it's max capacity).

*I believe one definition of insanity is repeating the same thing twice and expecting a different result!
 

hman

Active User
H-M Platinum Supporter
Joined
Feb 17, 2013
Messages
2,478
That would explain how my 6" 3-jaw came to be the way it is. As part of the renovation of my lathe I stripped down the chucks to clean out the old goo and chips. When I came to re-install the chuck jaws I fitted jaw #1, then #2 & #3 and wound them into the middle to check they were correctly timed - which they weren't! Repeated twice* before checking everything and finding #1 has a tooth broken off,
<snip>
*I believe one definition of insanity is repeating the same thing twice and expecting a different result!
Sometimes repetition is NOT a sign of insanity. Sometimes it's an example of "I made a mistake once ... thought I'd done something incorrectly, but I was mistaken."
 

dtsh

H-M Supporter - Sustaining Member
H-M Platinum Supporter
Joined
Sep 22, 2017
Messages
136
I doubt that a chuck with removable(reversible) top jaws was all that old. I have seen several chucks that were damaged in that same way.
I estimated it's age based on my understanding that Oneida National Chuck Co was taken over by Pratt in 1918; given it's possible that Pratt continued using the Oneida National Chuck Co name. As for the jaws, I don't think they are reversible, as the teeth have a definite curvature to match the scroll. I should have taken a picture of the side of a jaw, they are effectively flat, with a notch cut out in the middle portion of the face and the holes in the jaws are threaded, for what that's worth.
 
It can take up to an hour for ads to appear on the page. See our code implementation guide for more details. If you already have Auto ad code on your pages there's no need to replace it with this code
Top