Machsupport Forum
Tangent Corner => Tangent Corner => Topic started by: Overloaded on February 24, 2011, 03:51:15 PM
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Hey All,
To punch or drill .050" dia holes in .035" thick 260 (half hard) brass ...... that is the question.
There will be many, many to do.
A punch seems best but not sure about the punch dia. to material thickness ratio.
The punch will be quite fragile. Any thoughts on this ?
But to drill, initial speed and feed calcs show 18K + rpm with a .0002 or so chip load.
And the set-up would probably require two spindles.
Anybody got any light to shed ?
I'm torn :-\
Thanks,
Russ
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Russ,
I think getting a punch through is no problem but the material has to be held correctly when the punch is withdrawn, any movement here would risk a breakage. The punch could have a short head and reasonable diameter shank for strength so I would not see that as a problem but holding the material down is another story.
Tweakie.
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Hi Tweakie, I did a test and verified your thoughts.
I used a hard urethane bushing as a stripper and it punched much better than I had expected.
The fixture will have two punches relatively close together so the shank will be .25" max.
Should be no problem punching, greatly simplifies the job !
Thank you for your advise / input.
Regards,
Russ :)