Bison chuck question - 2 part jaws

If I understand you correctly then I too have a similar chuck that came with my Chinese lathe. Each jaw is in two parts that are held together with a socket headed screw. When the screw is removed, the outer part of the jaw comes away and can, indeed, be reversed. The joint is really quite complicated and, as long as its kept clean, appears to guarantee correct alignment - its a really neat bit of machining. I've used it quite successfully and it is certainly far better than the usual reversible jaws.

Gary

Thank you for the insight, it was just as I had hoped. Although my other chucks are reasonable this one seems particularly good and repeatable (at 1 inch anyway) and I didn't want to disturb it just to look.

I see that your version came with a Chinese lathe; do you find the lathe OK? I am still considering a bigger (6x24) lathe with a gap bed to complete my set as it were. Although I have been offered a couple of secondhand "British" lathes they are a little smaller than ideal and I am still tempted to dabble with a new Chinese one. My only experience with an import was a 20 year old 918 which had seen better days and was not a fair representation of the type. It certainly seems difficult to get any comments from someone who has bought and is using one now. They certainly look as if they have improved over the years and a current opinion would let me balance the argument a little. I'm not looking to start another "mine is better" topic just to see if they "do as it says on the tin" these days. My tin is very much an amateur repair and jobbing environment so I'm looking for a versatile and accurate machine rather than one which will remove an inch in a single cut and last for three lifetimes.

Thanks again

Regards

Keith

Keith, My lathe is a 12x36 (English designation would be 6x36) geared head that I purchased from Chester 4 or 5 years ago. It replaced a Boxford 5" CUD whose spindle bore was too small for me. I too use it for amateur purposes - I belong to a model engineering club and do voluntary work for REMAP. Initially there were some teething problems that Chester sorted out very satisfactorily, and since then it has proved to be a very worthy machine. One job I had to do (for a REMAP project) was to reduce a meter of 38mm stainless steel down to 25.4mm (don't ask why). It was accurate to 1 thou all along. Compared with the Boxford, there is no doubt that the finish of some of the controls is not as good, but it certainly doesn't lack precision. A couple of ME friends have used it for jobs too big for their own machines, and have been very complimentary about it. One friend (who has won gold medals for his ME skills), as a result of his experience with using my machine, purchased a similar but much smaller Chinese lathe for his grandson. Currently his grandson has nowhere to put it so my friend still has it in his workshop. Despite having a Pultra (as well as a 5" Southbend) he has been using it for some of his smaller jobs in preference to the Pultra.

Gary

Brilliant, that was just the sort of genuine hands on experience I was looking for. There appears to be plenty of "hearsay" available but few comments from those with actual experience. Although judging from my observations at Harrogate they must sell lots of these machines I suppose we are all a little guilty of only shouting when things are not "right".

I had thought about the geared head version but was a little concerned about the noise, particularly at high speed. I suppose my past experience of old Harrisons sounding like a turbojet spooling up has something to do with it. I see Chester has an open day shortly so if I can find time perhaps I will pay a visit and have a look (and listen) to what's available.

I was interested in your comment about the finish of some of the controls compared to your Boxford, I had this complaint with my old 918 which just did not feel nice to use. However, now that I have other machines available changing the handles shouldn't prove impossible if I found them obtrusive.

Having only recently bought the Boxford I was a little disappointed that I have already met the "small spindle bore" limitation. Still, I think I need to let my interests settle down a little before thinking about parting with it. One thing I have learnt is that good machines are difficult to find and I am lucky at the moment that I do have room for another larger lathe. My plan was to use a few machines for a year or so and then decide which ones to keep longer term. My wife has some doubts about this plan as she is convinced that my intention is to become a lathe (old junk!) collector.

Thanks again for your very helpful comments Best regards Keith