Opinions wanted on lathe chucks

[protrxrptr17]

The chuck on my lathe is totally worn out. I need a 4 jaw independent 18" chuck. My budget is very limited. Any suggestions? My current chuck bolts to a hub with 4 bolts. The hub attaches to the spindle with 4 studs. To remove the chuck you just loosen 4 nuts and twist a slotted ring. The studs and nuts slide through the wide end of the slot. I'm sure I confused everybody with that description.

Anyway, where do I need to look for a chuck? I can't afford much, but I need something that works. Any particular brand to stay away from?

[Runner4404spd]

alot depends on what kind of tolerances you need to hold. you can try wholesale tool, msc or KBC.

[DareBee]

With a 4 jaw independent chuck, you can almost buy anything. The are the most basic of basic things and it hardly matters if they are sloppy, however I still don't endorse buying garbage and have no idea your budget.
I am a big fan of Bison products, quality is good+ and they are inexpensive.
KBC sells this brand (as do others).

[handlewanker]

Hi Protrx, I worked on a VDF Lathe, German type, in the 50's, and it had this type of mounting. A very accurate and easy way to mount/dismount a chuck.
Only problem is most chucks you see on Ebay are the camlock type.
I don't know if your type is regarded as "special" now or if the camlock has taken over.
An 18" 4 jaw is big by any standards.
4 jaws suffer from "bellmouthing" when worn, and that can be corrected by grinding the jaws while held in compression with a ring at the back of the jaws, but the jaws are still floppy in the slots.
Difficult to set up as the jaws have to be individually ground, or if you're a masochist then try setting all four at once.
When you get a price for a new chuck, think about this method:-
Regrind the top and bottom guide faces of the chuck body where the jaws run, don't touch the side face guides. This will make the chuck body almost "good as new".
Next weld the top and bottom faces of the guide slots in the jaws, with HARD FACING WELD. Don't touch the jaw faces.
Lastly, grind the jaws to fit the slots taking in account the fit with the screws.
Do not weld the body of the chuck. Being cast iron it might suffer from cracking around the weld area, and as so little grinding is required to true it up then this is the best way to go.
You can also mill the chuck body slots with, and this is definately recommended, a carbide tipped flycutter, milling each slot top and bottom in one setting.
The jaws will have to be ground, and as this is a grind to previously machined sizes, could be sent out, if you don't have a surface grinder, but it will make or break the job if you don't get it right.
Once again the measurements to get the screws to mate properly must be right.
You could also machine the chuck body and get the jaws hard chromed and reground.
Never tried this and I don't know if the hard chrome will bond with the hard jaws. Maybe someone else can comment on this method, and a probable cost.
Whichever method is tried, the chuck body must be trued up first.
Ian.

[DareBee]

My books don't show an 18 only 16 or 20.
Your turn lock adapter plate should fit any standard plain back chuck.
a 16" Bison is around $800.
Handlewankers rebuild methods are right-on. Except a chuck body is usually semi-steel instead of CI; although weldability is still a concern (although better than straight CI).
I would be hard pressed to rebuild your chuck for the price of a new one and it would be still a rebuilt chuck.
KBC also lists an "inexpensive import" in 16" at $350 (gotta be China).
Maybe buy one of these new and keep your old one as a spare and for really rough work.

[RICHARD ZASTROW]

protrxptr17, Make sure whatever chuck you use is rated for the rpm it will be operated at. An 18" chuck will hold a heavy part. You don't want it rolling around the chip pan or anywhere else.

[CNC Pro]

I just purchased my Bison chuck, I’ve been very happy with it the week I’ve owned it. One note I can make on purchasing a chuck is SHOP AROUND! After settling on the model of Bison I wanted, I browsed the Internet, catalogs, and even contacted Bison’s US headquarters. By shopping around I was able to save $300.00 and get my chuck within 2 days (as I found out during my research, some dealers were on backorder).

[protrxrptr17]

I actually have two worn out 4 jaws and a worn out three jaw (a new three jaw is useless to me). The 4 jaws are bellmouthed just you described handlewanker. I think getting a new chuck would be more cost effective for me. I don't have a surface grinder, and the bodies of both chucks have been broken and repaired.

My lathe is German. Werkzuegmaschinenfabrik is the name. It's pretty old, but it still does a decent job. I could probably fit a 20" chuck, a 16" would probably do the job for most of my work. What do ya'll think?

CNC Pro, where did you buy your chuck? Bison seems to fit my budget and have the quality I'm looking for. I could probably afford about $800.

[CNC Pro]

Hey protrxrptr17,
I bought my 8” Bison “set-tru” chuck from Ajax Industries and they are located in Ohio.
It came with the backer plate, mounting bolts, instructions, and a
You can contact them at:

Ajax Tool Supply
575 N. Hague Ave
Columbus, OH 43204

Telphone: 800-642-6459
or 800-543-5998
Local Phone614)272-6944

Fax:800-552-5320
Local Fax(614)272-6945

www.ajaxjaws.com

I actually came across Ajax during an E-bay search. You may want to see what E-bay has to offer, as I’ve seen some large chucks (new & used) listed there, many at reasonable prices. I hope this helps and good luck on your search.