Greenlee punch question

[Magz]

1/8" I would definitely use a drill, punch would warp the box too much

I usually get little dimples in the Al or Cu right where the punch first cuts into the material when using a Greenlee punch, even with brand new punches. Are there any tips for avoiding those? I suppose I could use the punch so the cutting head is on the inside of the panel, but then I get scratches from the flat side of the punch contacting the plate.

Any pointers appreciated!

 

[mickeymoose]

I use masking tape to avoid the die marking the material, and lots of lubricant!
Too bad Greenlee does not supply their "Slug-Splitter" punches in anything other than conduit sizes! E

 

[Lavcat]

Last night I finished machining my panel, it only took me about a year and a half. For the 15/16ths holes I used the Greenlee punch but for the 1/2 inch holes I drilled rather than punching.

Thanks, everyone, for the help.