On 2008-12-07, Jim Wilkins wrote:
On Dec 6, 5:05*pm, Gunner Asch wrote:
pasted
On Fri, 5 Dec 2008 18:49:23 -0800 (PST), wrote:
For low volume work, what would you suggest?

Stainless steel requires 1.5x the energy as standard steel to
punch/shear
Roughly. Often times a bit more.
What size work piece and where the holes are at, makes a big difference
as well
Gunner

Punching pressure in mild steel:
http://www.roperwhitney.com/tech/chart1.cfm

1.2 Ton hand punches:
http://www.roperwhitney.com/punching/2-45.cfm

O.K. So even the XX size is too weak for a 3/8" hole in 20 ga
even in mild steel -- and certainly not in 304 SS.

4 Ton Deep Throat bench punch:
http://www.roperwhitney.com/punching/2-14.cfm

However -- *this* should do the job quite well. I didn't know
that they had that -- but I'm glad to see that they do.

I used the bench one quite a bit at one job. The lower die is tricky
to install, it's both located and held in place by four setscrews so
it shifts as you tighten the screws. Otherwise it worked quite well
for the one-off test equipment I was building. It didn't have work
guides so you need to center-punch each hole location and wiggle the
point on the punch into the dimple by feel.

Same problem with the hand punches. But they still make some
jobs easier to do.

Enjoy,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---