stummel chuck for 9" metal lathe

[maddis]

I've recently made the switch from a Jet mini to a South Bend 9" metal lathe for stem and stummel work. The SB came with a nice Cushman 3-jaw chuck and that should work fine for stems. Any suggestions on a 4/2 jaw chuck I should look into for stummels?

In terms of using my existing chucks, I did purchase a 1" x 8 tpi to 1 1/2" adaptor and it works *OK*. But my current chucks don't seem to spin as true with the adaptor as they do on my wood lathe.

[caskwith]

Does your south bend have a morse taper headstock spindle? If so get a morse taper arbor with the appropriate thread and a drawbar, you will find it much more accurate than a simple adapter that is normally used on wood lathes.

[maddis]

It came with a set of collets and a draw bar so I'm guessing that it does have a morse taper. Are you saying there's an adaptor that will fit my existing 1 X 8 chucks that fits into the morse taper, rather than screwing onto the threads of the spindle?

[caskwith]

It came with a set of collets and a draw bar so I'm guessing that it does have a morse taper. Are you saying there's an adaptor that will fit my existing 1 X 8 chucks that fits into the morse taper, rather than screwing onto the threads of the spindle?

There are a large number of adapters of this type available, I have one with my myford thread on it so I can put my myford chucks into my wood lathe. If there isn't one available and you have a metal working lathe then you can make any adapter you need.

[caskwith]

Here is a live version I found on ebay, you just need a fixed version basically and a draw bar to go with it. DO NOT use this kind of system without a draw bar, if the taper came loose while turning it would be very serious!

http://www.ebay.co.uk/itm/Live-Tailstoc ... 35c162f3aa

[maddis]

It came with a set of collets and a draw bar so I'm guessing that it does have a morse taper. Are you saying there's an adaptor that will fit my existing 1 X 8 chucks that fits into the morse taper, rather than screwing onto the threads of the spindle?

There are a large number of adapters of this type available, I have one with my myford thread on it so I can put my myford chucks into my wood lathe. If there isn't one available and you have a metal working lathe then you can make any adapter you need.

I've spent a good bit of time this morning searching the web and can't seem to find a dead version of this. One guy in England is selling them, but they don't appear to be threaded for a draw bar. I wonder if this is the sort of thing you need to make, which would not be an option for me as I haven't yet figured out how to do any metalwork on my lathe. And on top of that, I haven't made a pipe in two weeks cause this change in tooling is throwing me off my routine!

[caskwith]

It came with a set of collets and a draw bar so I'm guessing that it does have a morse taper. Are you saying there's an adaptor that will fit my existing 1 X 8 chucks that fits into the morse taper, rather than screwing onto the threads of the spindle?

There are a large number of adapters of this type available, I have one with my myford thread on it so I can put my myford chucks into my wood lathe. If there isn't one available and you have a metal working lathe then you can make any adapter you need.

I've spent a good bit of time this morning searching the web and can't seem to find a dead version of this. One guy in England is selling them, but they don't appear to be threaded for a draw bar. I wonder if this is the sort of thing you need to make, which would not be an option for me as I haven't yet figured out how to do any metalwork on my lathe. And on top of that, I haven't made a pipe in two weeks cause this change in tooling is throwing me off my routine!

Adding your own draw bar thread shouldnt be too difficult, drill and tap in the back end for a piece of threaded rod.

Failing that find a friendly local machinist/machine shop and ask them to make you one, a blank arbour should be well under $10 and it only needs threading then. I have made many of my own arbours this way for various chucks etc.

[Sawdust]

I have the same problem with my wood lathe (a Conover) because it has the same spindle nose as your 9” South Bend. Here is a quote by Ernie Conover about the design of that spindle:

“A Conover Spindle is copied from a South Bend 9" Lathe. It is a 1-1/2" DIA Spindle with 8 Threads per Inch. The Spindle is 7/8" long to the shoulder, but only 11/16" is threaded. The remaining 3/16" is a centering band that is proud of the thread. The DIA is 1.509". All accessories have to be counter bored to 1.510" DIA for a little greater than 3/16". 7/32" is a good working figure and you can go 1/4" with no problem. This scheme ensures perfect centering of faceplates, chucks and such every time even though the thread is only a class III.”


To compound the problem, the Asian threads tend to be smaller than the regular SAE standards so if your adapter is only catching a couple of threads then there is not much you can do. If it is threading all the way to the centering band then you can turn a relief and reduce your run out. Here is a link to another forum where the poster solved this problem:
http://www.woodcentral.com/woodworking/ ... lustrated/

The only specific fit chuck that I know of is the Oneway Stronghold. You need to specify the Conover adapter (#0302). Here is a link:
http://www.packardwoodworks.com/Merchan ... 1ow-strong

If you need an adapter then these people should be able to help you out:
http://bestwoodtools.com/ Take a look at their adapters under wood turning tools.

Sorry about the long post, but I have had the same issue for over 25 yrs and share your difficulties.
Jim

[maddis]

Thanks Jim and Chris! It looks like bestwoodtools has what I'd need. They sell a fixed headstock chuck adaptor and draw bar for under $100. Just so I'm sure though...the idea is to use the draw bar to pull the adaptor into the spindle, right? And then you leave the draw bar in place, while the lathe is running, until you need to push the adaptor out?? Pardon my ignorance - metal lathe newbie here...

[caskwith]

Thanks Jim and Chris! It looks like bestwoodtools has what I'd need. They sell a fixed headstock chuck adaptor and draw bar for under $100. Just so I'm sure though...the idea is to use the draw bar to pull the adaptor into the spindle, right? And then you leave the draw bar in place, while the lathe is running, until you need to push the adaptor out?? Pardon my ignorance - metal lathe newbie here...

$100 sounds awfully expensive, I could probably make you one for less than that. My own adapters cost £5 for the blank and then I thread them myself, the myford adapter was bought pre-made and cost me about £15 i think.

But yes you are right, the drawbar pulls the arbour into the headstock, it doesnt need to be very tight, i only use my hands to tighten mine. The idea is it stops the taper coming forward and loose during use. When you need to remove it you just loosen the the nut and give it a tap with a hammer and the arbour should come free.

[maddis]

Thanks Chris - I may take you up on it if it's worth it to you! I can see where knowing how to use a metal lathe for making accessories would come in handy.

[caskwith]

Yeah it's worth learning, there are loads of videos on youtube on using southbend lathes and how to thread with them, get some scrap aluminium in and give it a try. Otherwise check in your local area and see what people around you might be able to do.

If it really comes down to it I could have a go for you, I think my wood lathe uses a 1 x 8 thread so at least I will have something to measure against.

[smokindawg]

Maddis, you could do as I did. I purchased a scrolling wood chuck from grizzly tools. They have one that will fit your spindle. The bolt pattern for the jaws is the same as the Oneway chucks, but the screws are smaller. So I just drilled out two jaws and re-threaded the holes to accept the same screws as the Oneway.

I then just bolt the jaws I made onto the cheaper chuck from grizzly that fits my lathe. The chuck is China made but is well made and works great for my pipemaking.

Here is a link to a scrolling wood chuck that will fit your lathe.
http://www.grizzly.com/products/4-Jaw-C ... -TPI/H7820