5-C Closer Questions

[Wess]

Hello All,
I am building a collet closer for my 12 x 36 lathe and have a question on the design. I am looking at this gentleman's design and noticed that he keyed the handwheel end of his so the tightening action is at the collet end. http://www.kinzers.com/don/MachineTools/collet_closer/
I was planning to have mine just threaded on the outboard end with that doing the tightning. Is there some advantage to the keyed end that I am not seeing? It seems to me to be six of one and half of dozen of another.

[TGTool]

Are you thinking of an external nut that pushes the collet in to clamp it, or are you thinking of using the collet's threads and turning (threading) it in to do the clamping?

The first sounds possible though you won't be able to turn quite as close to the collet because of the nut. The second won't work because the turning and wedging (clamping) friction will conflict.

If you're still open to options, you might check Metal Lathe Accessories which has a kit for a 5C collet adapter that also does not require a drawbar. Or, if you haven't comitted to 5C you might consider the ER collet spec that is front closing.

[ptjw7uk]

The hand wheel has to be keyed or fixed to the tube as the tube has to be turned to pull the collet closed. The only problem is the keyway for the collet to stop that turning so the closing action will work.
You dont have to ket the hand wheel just pin it in some way once the collet has pulled in sufficiently then the taper action should help with the tightening action.

Peter

[macona]

I dont know what that guy is talking about but all the 5C collet chucks I have seen have a key that prevents the collet from turning. The drawtube and handwheel are one piece with a bearing taking the thrust.

Ahh ignore that. He was referring to a pin to lock the adapter into the nose of the lathe.

[JCHannum]

I think he is asking if the draw tube can be used to draw the collet in by the threads on the handwheel rather than the collet threads. I suppose it can, but the collet threads are usually used.

The construction in the link is a but more complex than need be. Royal and most others simply use a flanged hub for the handwheel and that end of the draw tube is retained by grub screws or pinned.

[Wess]

Thanks guys I will go ahead a key the end and fix the hand wheel. Jim H. is correct that I was trying to ascertain if I could use the threads on the hand wheel end to pull the tube instead of the collet threads.

[Boucher]

Lever vs handwheel collet closers

My lathe came with a Royal lever type collet closer that had never been installed. If you are going to do repetive operations the lever would be nice. For ocassional use in my shop, I chose to modify it to use a hand wheel. I have been very pleased with its operation. If the accuracy is not a significant issue I would look at one of the collet type chucks. The lever is in the way if you are not using it or else you have to remove it. In my case saftey switches on the door panel have to be dealt with and the brackets to hold the lever are difficult to mount and cause other access problems. I use a 6 jaw run true chuck. If you dial it in it works better for 98% of my projects.