Lathe chuck adapters

[David Dockstader]

The PSI 5/8" x 1" x 8 adapter fits my two Shopsmiths perfectly and the PSI Barracuda chuck runs true on it. If Grizzly's chuck has a 1" x 8 thread, I can't see why it wouldn't run on this. If it doesn't, send it back and buy a Barracuda.

[Brice Rogers]

Yes, Mark, I saw that. For some reason most of the 5/8" shopsmith to 1" x 8 adapters are not made that way. If they were made more like an insert, as the one you reference, it would shorten the overall length and would also help with potential runout.

If you cannot find one of the shorter insert-like adapters, then plan B would make sense. Just buy one of the several conventional 5/8 to 1" x 8 adapters. They are fairly inexpensive and are intended for exactly your intended use.

[Mark Burnette]

Seems like I could also make an adapter bushing out of a short 1"-8 hex bolt, with a 5/8 bore through it. Add a grub screw through one of the flats to lock it on the spindle.
Turning a nice shoulder on the back of the head should reduce run-out.

I'm not a machinist but I work with some.

[Brice Rogers]

Mark, I machined my own adapter (5/8 x 16 M to 1 x8 FM) and there were some challenges to getting really low runout. I would NOT recommend starting with a bolt. The threads on a bolt are rolled rather than cut, the head is probably stamped/forged and nothing may or may not be perfectly concentric or perpendicular with the axis or the head of the bolt.

But, what the heck, give it a try and report back how it works. Also, perhaps your personal requirements for run-out are more relaxed than mine.

[Bill Blasic]

The easiest thing to tell you is this: Buy a Nova Chuck with insert INFS Insert F 5/8 Plain Bore RH or a Oneway Chuck with their 5/8 insert, either of these you stand the best chance of running the best and true and it makes them a direct fit to your machine.

[Clint Bach]

It's a no brainier.... Buy the psi Shopsmith adapter... The Shopsmith spindle doesn't run all that true no matter what you put on it. Nothing runs true on my Shopsmith. I like the Shopsmith anyway. You don't need no stinking new chuck.

C

[Clint Bach]

I reread the thread. You haven't purchased the grizzly chuck yet? Anyway, even though I haven't used my grizzly chuck on my Shopsmith, the chuck is more rigid and better machined than the Shopsmith. Don't expect great performance from your Shopsmith with any chuck. Almost any cheap lathe will probably out perform your Shopsmith as a wood lathe.

[Mark Burnette]

I bought a Nova G3 but on examination it looks weak and I don't like the open back. So I started looking again.
The Grizzly T10810 chuck kit looks to be a good value. IMHO they're limiting the appeal by threading the body so it only directly fits 1"-8 lathes. They should make it to accept the array of inserts already available that fit 1-1/2”-8 bodies.