Chuck thread converters.

[Munty Scruntfundle]

Hi there.

I'm thinking of upgrading from my current Axminster 305 to a chunkier machine in the spring, this one is great but I've started to push the limits of the motor's torque and sadly there isn't an easy way to upgrade just the motor.

Over the summer and autumn I built up a reasonable collection of chucks jaws and accessories, everything with a thread is 1x8. Of course nearly every new lathe coming out now is 33mm.

So my options are sell all the chucks I have and replace them, (I have asked if they can be changed, or the drive axle modified, there are no services to do so.) or use a converter block thing.

I'm not keen on the converter, it's another thing in the drive train, it's another possible problem, and I don't want to push work further down the bed than needed. However, I might be completely over thinking things and everything will work perfectly.

So, over to you folks. Does anyone out there use one of these converters all the time? Occasionally used one? Used one at all? Thoughts? Pros and cons?

Many thanks.

 

[Phil Pascoe]

https://www.charnwood.net/products/prod ... athway-174
I use a larger one on a bigger lathe and have no problem whatsoever with it.

You have a fairly small lathe so are unlikely to put anything ridiculously large and/or out of balance on it, and on occasion having the workpiece a little further from the headstock makes the working of the back of it easier.

 

[TopCat 32]

have a look at toolpost, there versa chuck has carriers to take most jaws, buy the chuck and back plate to fit new lathe then purchase the carriers for your existing jaws, i take it all your jaws will fit the same carriers, you are then future proofed as if you change lathe again and it has a different thread all you do is buy a new back plate, service is good , product is high quality, i had same problem a few weeks ago changing from 1" 8tpi to M33X3.5 and after loads of research this is what i went for, plus there wide range of jaws are well made and cheaper than axminster

 

[Robbo3]

You haven't told us what chucks you have. Some have replaceable inserts. Presume you have checked.

 

[Richard_C]

I thought about this when I got my Record chuck, not had to deal with a lathe change yet but it occurred to me that if I do I can get an adapter.

The chuck is (say) 70mm deep so the workpiece face is already 70mm out from the inner end of the threaded drive shaft. If you add an adapter you aren't adding the full length of the adapter, assuming it screws fully down on the drive shaft and fully in to the chuck you are only adding about half the length. The face of the chuck/end of the workpiece moves out from 70 to about 105 mm, not really material particularly as the plane of a bowl blank center of gravity will vary far more than that. A 4"/100mm thick blank centre of gravity will start out 155mm out, not 120, a 30cm spindle c.o.g. will be at 255 not 220 but a spindle is supported at the other end anyway.

(all sums done in head, corrections welcome)

There might be a slight worry if you have a reversing lathe.