[TheForge] Punching holes with Hydrolic press

[Bob Ehrenberger]

Just a follow up from the question I asked a couple months ago about die 
clearance on a punch press.

I finally got another order for the items that brought up the subject the 
first time. I needed to make 1" holes in 16ga sheet metal. First I thought I 
would try a bolster that I already had that was way too big, like 1.5".  It 
punched the hole but pulled a lot of material in with the punch, and left it 
connected at one point. Saturday I made two new bolsters, one out of 1/2" 
round and one out of 3/8" sq, both have about .030" clearance on the punch. 
I tested them last night and both worked well knocking out a nice slug, the 
one made from 1/2" round did pull in some material which could be a useful 
effect on some projects.  I check the alignment between punch and bolster 
without material and then put the sheet metal in and punch the hole.  The 
only problem is that the material sticks to the punch and has to be knocked 
off after raising it up.  It's a whole lot easier than drilling big holes in 
thin material.

Robert Ehrenberger
Shelbyville, Mo.
eforge at centurytel.net