Thread: Punch clearance
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Ed Huntress Ed Huntress is offline
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Default Punch clearance


"Snag" wrote in message
...
Buerste wrote:
I have a die that blanks a 4" round from .42" cold rolled dead soft
steel. I need to blank .32" thick drawing steel. Do I need to make a new
punch? The clearance for the .42" (19ga) is .004" per side and the
clearance for the .32" (21ga) should be .003" per side. (I think) The
blank will then be drawn into an eyelet with a 2-1/8" id.


Uhhhhh , I think you left a zero out there , Tom . .42" for a grommet ?
I'm bettin' the die you're using will work , though I know absolutely
nothing about punch press work .
What can it hurt to try a piece or six ?
--
Snag
Wannabe Machinist


This is guesswork, but my bet is that it will shear, but it will leave one
heck of a burr.

The other possibility is that it will produce an especially thin-wall deep
drawing g, probably half torn.

--
Ed Huntress