Using Collets in a SB 10L?

[Halfnuts]

Just got my new/old mid-'60s 10L home. It has the large bore 2 1/4 x 8 spindle. I gather the collets for this lathe were a proprietary size that only SB made, but that a 5C adapter is needed.

I'd like to be able to run collets, and as I understand it, there are a couple of drawbar-type collet closers, either lever or handwheel-type, and there are also collet chucks available. I suspect there's an advantage with regard to accuracy when the collet stays within the spindle, rather than hanging out in front in a collet chuck. But I don't see that collet closers are available for the 10L large spindle, and I also don't see the 5C to SB taper adapters, either. What am I missing?

I expect to be doing a lot of work on small stuff, so I'd really like to use collets whenever possible. What are y'alls' recommendations for a noob like me?

 

[itsme_Bernie]

You want the proprietary 5C spindle adapter, and a simple drawbar. 5C is a dream. Closers etc are for lots of repetitive work. Otherwise they are in the way, noisy, and block access to things.

This is a slanted view. I have used both, and primarily use 5C collets. I rarely would have benefitted from a closer setup.

There are few reasons (not none, but very few reasons) to think about a collet chuck unless your spindle is too small for an adapter. I think Ray C is the only person to ever come up with one I could see.

Another great reason is you just keep your eyes peeled on Ebay for a few weeks and you'll find an adapter for $50 or so bucks. Same for the drawbar, or you can make one!

I'm not saying people don't thoroughly enjoy having a collet closer setup on their machines at home, but you need to justify finding one, complete, and paying for it. I wouldn't want one.


Bernie

 

[wa5cab]

A drawbar is is a solid member and is used on collets that do not allow for passing the workpiece through the collet and spindle. Common collet types are 2MT, 3MT and R8. They may require an adapter that fits the spindle nose on its OD and fits the collet on its ID. Common collets that allow the workpiece to pass through the collet are 3AT, 3C and 5C. With your spindle bore, you would certainly want to go with 5C. Cost of the collets is substantially the same and the 5C can go to slightly above 1" diameter workpiece whereas the other two are limited to 17/32" diameter.

The 5C on an SB will require a spindle nose adaptor and a draw tube operated by either a handwheel or a lever. The lever type is much faster to use (i.e., to change workpieces in) but is considerably more expensive and takes much more time to convert between chuck and collet operations.

Collet chucks are generally quite expensive and the only reason I can think of for using one would be if you want or need to use a collet size that is too large for your machine otherwise, For example, a 5C collet on an Atlas (whose spindle has a 25/32" bore, too small for a drawtube that fits a 5C collet).

There is of course a totally different style collet patterned after those used in a Dremel tool. These have names like ER-25 and ER-32 and are made to French metric specs. They require a collet chuck that is closed by a compression nut over the front of the collet. The nut is tightened with a wrench. They are somewhat less convenient to use than the handwheel operated draw tube.

Robert D.

 

[itsme_Bernie]

Thank you Robert- I was mis-speaking calling it a "drawbar" when the Heavy Ten 5C system uses a "handwheel-drawtube".

As you mentioned, this allows stock to go straight through.


Bernie

 

[Halfnuts]

Thanks for the clarification. Next question, is anyone making them still, or do I have to wait for one to come up on eBay? It seems something like that would not be hard to make, although I suspect the adapter needs to be made with precision. Miller Machine makes spindle adapters but it looks like they are Morse tapers; no mention of the oddball SB taper. And tools4cheap offers the handwheel-drawtube type closer but only for the 3C, not the 5c collets.

 

[itsme_Bernie]

Call Miller Machine and ask. But they do come up on EBay pretty often. They also, pretty often as a set, with the drawtube, spindle nose adapter, thread protector as a set. The thread protector does exactly that, but also helps remove the spindle nose adapter when you Unthread it. Again, usually comes in the set when you buy it that way.

I have almost your exact machine- what base are you mounted on? I have the floor model, as opposed to a bench.

Bernie

 

[Halfnuts]

I didn't know there was a bench model for the 10L. Mine's mounted on the twin pedestal "sheet metal" - heh heh - cabinet with underdrive. It's model no. CL 187 A.

You can see the cabinet in the background behind the sweaty guy schleping the lathe on the chainfall.