I would think your bend radius is too tight. Also, your metal might be too hard.
Paul
We are bending parts cut from our CNC plasma cutter in a 60 ton Accurpress. Using a 2" wide bottom die.
When bending .250 the metal tears where a 90 degree corner meets. We can design around many of these corners, but some have to be there. I've tried putting a .250 hole in the edge of the corner, but it still tears from inside the hole, sometimes .375 or deeper.
Any ideas?
I would think your bend radius is too tight. Also, your metal might be too hard.
Paul
A couple of things I have done in the past is radius the edge in the bend area, this will spread out the stress, also I have greased the die to allow the plate to slide easier. What kind of plate is it?
try a larger radius top punch. also the heat from the plasma may cause the metal to be more brittle near the edge.
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http://www.cnczone.com/forums/showthread.php?t=86985 my work in progress
got any pic's you can show us?
JerryFlyGuy
The more I know... the more I realize I don't
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)