Machinist

[Lawrence London <lfljvenaura@gmail.com>]

Making a 5C-dead center. - Page 2
http://www.practicalmachinist.com/vb/general/making-5c-dead-center-194756/index2.html

headstock dead center with flange and drive pin in same axis as spindle to eliminate need for drive dog on workpiece

That will work.

I recommend reducing the diameter of the collet end, forming a shoulder to support the stress of the workpiece as gbent suggested.

- Leigh

And to take this idea a little further: I have found it very convenient, when practical, to make the headstock center in a collet as suggested but also use stock large enough to also make a flange that extends radially from the base of the turned cone. In that flange I place a drive pin whose axis is parallel to the spindle axis. In the work piece I drill a hole 30% or so larger than the pin. The pin engages the workpiece hole and drives the work. This eliminates the need for a lathe dog. (I certainly also use dogs but much prefer to not have them whirling around just looking for something to bite) it does not take a very heavy pin to drive the work most of the time.

Denis

P.S. Besides eliminating the dog, this method allows machining the part from one end to the other without the need to flip it. I think that is why I did it in the first place. But I liked it and, so, have used it often since

Other comments:

I have a Hardinge lathe with a 5c spindle and a drive plate, but no 5c dead center. I expected to find a bunch of these on ebay but at the moment there is only 1 for more then I am willing to pay... So I was thinking about making one and wondered what people thought would be the best way to go about it.

I was thinking about making a 5c blank to fit the spindle, then put the blank into the spindle and rough boring a MT2 taper into the blank, and finishing it off with a MT2 reamer. After that I can just insert normal MT2 dead centers into the 5c adapter.

Does this sound like it would be accurite? or should I just make it out of 1 solid piece and heat treat the 60deg point?

Thanks,
Tyler

You can buy from Hardinge a 5C blank bored for MT1, MT2 and I think, MT3.
I bought these for use in my Hardinge horizontal mill but they could be used for the application you have in mind. There was a PM fellow some time ago who was selling new/old factory stock MT2 dead and live centers of many types for bargain prices. You might find the ad in the tooling 4 sale section and contact him. He also had arbor sets...You can also buy Hardinge 5C blanks for around $25.