Exit Wounds and De-burring

[aucran]

Hi,

Does anyone have any tips about deburring holes, especially the back end, of thin material. I tried using a countersink bit (they work great for the entrance end) but sometimes it just flattens the little spikes of metal that stick up instead of cutting them. Right now I'm just using a larger drill bit and twisting them off by hand. But this doesn't really produce a smooth counter-sink,

The material I'm working with is 1/16" THK AL Angle.

Thank you

[metalworkz]

Hi,
I have had very good luck in a precision sheetmetal shop environment using Weldon fluteless countersinks for deburring with both aluminum and steel parts.
You can mount the c'sink bit in a hand drill and make quick work for touch countersinking the burrs off. Most other bits with flutes will chatter and these Weldon bits cut a very clean edge on the burred holes. You can also make a small hand held arbor to hold them and do holes by hand in a twist when there are not so many holes to do. There are also some whip type deburr tools that are shaped something like a hook that do a fairly good job but for me they are somewhat awkward to manipulate.

[rbcmetalwork]

You could try using a sacrificial sub-plate when drilling the holes so the back side doesn't blow out. This will minimize the burr.

[ewequipment]

http://www.shaviv.com/ I hope this helps.