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ChrisJ
03-01-2005, 01:40 PM
I have some 4mill 316SS stock and need to punch some 1/4" to 1/2" discs out of the stock, where the disc is the product of the punching exercise.

Does anyone know of some hand punches or dies for this operation?

Chris

2muchstuff
03-01-2005, 02:08 PM
Chris,
4 mil. stainless is some pretty stout stuff. I don't know of any hand operated punch that would have enough force to punch out the discs. You may have to go to a tool and die shop and have them punched out on a large press. They may have an individual die or be able to use a part of another more complex die to get you what you need.

ChrisJ
03-02-2005, 10:10 AM
Thanks for the reply.

I thought of making a die/punch.

How about two pieces of bar stock. One side gets some 1/4" to 1/2" drill rod stock, with the ends cut at an angle protruding from the face only as much as needed. Other bar mates up with the drill rod with holes to receive the drill rod.

Will the drill rod cut/shear the 316SS sheet?

Chris

2muchstuff
03-03-2005, 12:36 AM
Chris,
Drill rod by itself won't hold up very well. It has been a few years, let's see what we can pull out of the old void between the ears. I would start out with some nice die stock, either A-2 or O-2 stock (machineable). Machine out your die (bottom piece) a few thousands undersize. Lathe out your punch (top piece) a few thousands oversize to onsize. The punch has to have a flat/square cutting surface. The reason for this is if angled the punch will want to "walk" when it comes time to punch and your discs will come out cresent shaped. The movement in the punch will cause it to fracture.
Then take your newly machined parts to your local heatreater and have them hardened to about 65-67c, then stress relieved.
When the parts come back (no longer machinable) they need to be sharpened on a surface grinder. I believe the punch needs to be about 3 to 5 thou. smaller than the die hole for the thickness of material that you are using and several tons of pressure. The punch and die then will get mounted to a die set so they will be in perfect alignment when used. When they are not aligned and it comes to crunch time.........ouch, a crashed die in not a pretty sight. This is it in a nutshell, hope it helps you out some.

ChrisJ
03-03-2005, 06:50 AM
Thank you very much.

Chris