Warco WM250 Chuck maximum size

Hi, I have a Warco 250 lathe which comes fitted with a 5”..125mm chuck..A friend has a nice Pratt 6” chuck that he no longer uses....would this be too big for my Warco?

The radius is only about 1/2" greater than the original, so there is a pretty good chance of it being ok. Check how much clearance there is with the jaws on your present chuck extended to simulate the biggest size the chuck is intended for. You may loose a little length with the bigger chuck. The Pratt would be an advantage in capacity and quality, I hope it comes with both sets of hard jaws.

On my WM250V, there'd be just less than 1/2" clearance between the lowest point of the 5" chuck and the top of the crossslide - if you could get it that close to the headstock, which just can't quite do because the telescopic leadscrew cover bottoms out.

So I think that if the 6" chuck is deeper than the as-issued 5" - which it likely is - you might want to rig up some kind of additional stop to avoid collision risk. The compound slide would probably still give you enough reach for close-in chuck work like parting and boring, but that's a bit of a guess.

My self, I'd wanna be really sure both that I needed the extra capacity, and that I could get the new chuck as true as the issued one - I think mine is the best I've ever used.

Edited By Mick B1 on 28/07/2019 18:18:18

This thread, about a month ago, might help.

**LINK**

I have a 160mm chuck on a Warco 250. The leadscrew cover stops the cross slide hitting the chuck body but if you're holding large diameters it is definitely worth checking the jaws and cross slide have clearance.

Seeing that 160mm chuck, 6.3" on the lathe suggests to me that even a 6" would be too big. The jaws cannot be positioned much past the OD before hitting the bed, so your 5" could probably hold larger diameter stock.

With the jaws the way around in the pics the chuck can hold 90mm dia stock and just clear the cross slides bed, it wont crash due to the leadscrew cover. Chances are with a tool mounted you'd hit the jaws with the tool tip first anyway. I haven't checked with the jaws reversed but when I took the skin off a 130mm dia piece of cast iron there was loads of clearance.

From my Boxford days with screwed on chucks,faceplate etc it has become a habbit to take them away again as soon as job is finished.

Enterring the chineese bolt chuck country was a maddening expirience.

I have thinned the flanges of all the four blue lathes I have had.

Chuck change is now less than two minutes start to stop.

My advice will be to get the lovely non chinese 6 inch chuck and exchange the 5 inch chucks for 4 inch dittos.

4 inch chucks are so much easier to handle and put on spindle and will do 95% of the jobs.

Picture is a 5 inch taking off from my WM250 lathe.

Edited By Niels Abildgaard on 29/07/2019 08:16:29

Thanks guys...