Machsupport Forum
G-Code, CAD, and CAM => G-Code, CAD, and CAM discussions => Topic started by: Keith on January 13, 2015, 05:56:06 PM
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I'm having a bit of a problem peck milling. I've had recent success with some relatively larger hole. This time around, I'm drilling down .375" into a .0555 diameter piece of polycarbonate with a .031" drill (of high quality). I'm using the longer retract method. The hole comes through okay (the fixturing is a bear) but the inside walls seem to have a spiral cut into them looking a lot like the spiral of the drill bit (but probably just an artifact of whatever is not right).
Any suggestions are appreciated. I read some where this might be an anomaly of not enough dwell at the end of a peck and then rapid-ing above the last height.-Keith
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I would think this happens because one flute of the drill is dragging on the way out. Maybe the spindle isn't perfectly square to the Z axis.
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What RPM are you drilling at ? A drill that small needs to be zinging along RPM wise to cut smooth.
Just a thought, (;-) TP
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I was going quite slowly because I thought a high speed would melt the polycarbonate. So then what about a 'feed' on this; fast as well?
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This may help
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Thanks, that 'puts a face on' what I was missing. I'll experiment with these ideas.-Keith
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Thanks for the PDF link Terry - I have just learnt things I did not know about drilling acrylic.
Tweakie.