3 Jaw Chuck restoration. Can't figure out how to take apart

[JReimer]

Hi,

I am in the process of fixing up an old lathe that came with an interesting 3 jaw chuck. It is interesting as it has both a scroll for all 3 jaws (typical) and independent on each jaw (like a typical 4 jaw). I can't seam to figure out how to get the back scroll off and it seams to be jamming on something internal. I don't want to force it as I am not sure what is going on. I thought the ring (3rd image green arrow) was used to capture the scroll place but it doesn't have a pin or set screw and I can't seam to get it off. Anyone have any ideas? I haven't broken out the bigger hammer... yet. it's a JW Westcott.

 

[Tom O]

I got this from one post but the link is probably more helpful.

Yes, saw that thread in my Google search and the patent drawings at Vintagemachinery.org. Still doesn't tell me how one would go about getting the retainer pin out. There was one 'slide hammer' comment in bytewise's post, but can't see how that could attach to anything.

How do I take a Westcott 3 jaw chuck apart?

There was a topic posted on another forum where a person had trouble taking one of these apart. I have one that I was pretty sure is beyond repair, and needed cleaning. So, off I went trying to disassemble it. There are a couple steps missing probably. But the important thing is that the...

www.hobby-machinist.com

And check this out under the cap screws holding the pinions in.

Well thanks to Ken's links, I found out why my Westcott chuck wouldn't come apart. The pin holding the pinion in was bent (I did it). The pin was held in a blind hole with a cap screw, so I drilled in from the back and was able to drive the pin out. Once the pin was out the pinion fell out and I was able to push the back of the chuck out. Success!!! Thanks guys, I was able to salvage this chuck.

 

[JReimer]

I got this from one post but the link is probably more helpful.

Yes, saw that thread in my Google search and the patent drawings at Vintagemachinery.org. Still doesn't tell me how one would go about getting the retainer pin out. There was one 'slide hammer' comment in bytewise's post, but can't see how that could attach to anything.

How do I take a Westcott 3 jaw chuck apart?

There was a topic posted on another forum where a person had trouble taking one of these apart. I have one that I was pretty sure is beyond repair, and needed cleaning. So, off I went trying to disassemble it. There are a couple steps missing probably. But the important thing is that the...

www.hobby-machinist.com

And check this out under the cap screws holding the pinions in.

Well thanks to Ken's links, I found out why my Westcott chuck wouldn't come apart. The pin holding the pinion in was bent (I did it). The pin was held in a blind hole with a cap screw, so I drilled in from the back and was able to drive the pin out. Once the pin was out the pinion fell out and I was able to push the back of the chuck out. Success!!! Thanks guys, I was able to salvage this chuck.

Hi Thom, yeah I had seen that one so was looking for a pin, but my chuck is slightly different. Found this thread with the same type of chuck but haven't gotten any farther on disassembly.

https://www.practicalmachinist.com/forum/threads/j-h-westcott-new-combination-chuck.375100/

I read the front of the chuck more clearly and it is a "JH Westcott's New combination chuck, Special Jaw"

 

[JReimer]

I think I found one of the patents for this Chuck. it shows the ring (in my image with the green arrow) either being held on with a screw (not on mine) or it's a nut on threads... again I can't see threads. This at least gives me some confidence on where I should start with the hammer. Light at first of course.

Vintage Machinery - Westcott Patents

 

[Tom O]

Maybe try here although it didn’t come up in the search I did but it’s connected to vintage.org https://www.owwm.org/search.php?search_id=unreadposts

Well take out all the bolts first knowing there’s a pin in there before your drum solo not heavy though I’d suggest “Ina Gada Devita” maybe 3 times that should take care of it.

 

[6.5 Fan]

Tom O would that be the short or long version of "Ina Gada Devita" that you would use for the drum solo?

 

[Susquatch]

No idea how to take it apart but just have to say that it's a very cool chuck! I would love to have one like that for a newer lathe!

 

[JReimer]

Still can't figure out where it is supposed to come apart. I wonder if it is just a compression fit with that bronze bushing? the one mark on the side really feels like it should be a pin or screw but it was drilled out before I got this chuck and I have tried hammering at it and nothing is moving it doesn't appear to have anything in it (don't know if it comes across in the pictures).

Any other ideas on what I might be missing?

 

[JReimer]

FYI - the reason I am trying so hard to get the back scroll plate off is because there feels like there is something jammed in the scroll work and I can't move it very far without it binding. I would love to wind the jaw cradles out but it keeps binding up and I don't want to force it.

 

[Tom O]

What is that in the lower jaw is that a pin?

 

[JReimer]

Hi Thom - thanks for the idea. I think that mark you are looking on is on the jaw carriage. I can't find a pin in there anywhere.

I can open the scroll to this far (image below) and then it 'hits' a hard point that I am hesitant to hammer through as I am worried about bending a pin... but I have never seen a scroll that has a stopping point without being able to remove the carriages... Should we Vote - who thinks I should hammer the scroll around past the stop point? there is still a along way before the carriages are past the scroll nothing is loss.

the only think I can think of is that the groves on the back of the carriages aren't continuous across the entire back so they could be stopping the scroll from unwinding further but that seams harder to make and probably not the case... I think.

 

[Susquatch]

I vote against hammering on it. I wouldn't do that till you are ready to throw it out. I think you are a ways away from that yet.

 

[JReimer]

I vote against hammering on it. I wouldn't do that till you are ready to throw it out. I think you are a ways away from that yet.

that's a good call... but I can't think of anything else to try. This might end up siting for a while.

 

[JReimer]

I DID IT!!!!!!

not to be to dramatic.

So...

I first placed it on the lathe and lightly tapped on the back of the chuck which got it free from the back plate. It was just a compression fit (after the bolts where out) so it came off easily. I just couldn't hold onto the plate untill I placed it on the lathe.


Second: This gave me the confidence that the ring (green arrow pointing to above) was a retention ring like I first assumed. The trick was it was screwed on and now that the back plate was off I could faintly make out the threads. The dent in the side of it wasn't for a pin but where in the past they used a punch to drive the ring tight. I had tried this previously but it didn't move because the back plate was in the way and I wasn't confident in my "Ina Gada Devita" solo. With alot of tapping I got it off.



The pin in the carriage was what was stopping the scroll from completely loosening so yeah very good idea not to wail on the scroll work.



Thanks everyone for links, ideas and being a good sounding board as I hit my head against the wall on this one. (some of the pieces disassembled below)

 

[6.5 Fan]

Good that it came apart before the hammering commenced.