Drill bits for drilling aluminum...

[Michael Dunn]

What type of drill bits are recommended for drilling aluminum? Where can I buy them? Last time I tried to drill a 5/64" through 3/4" with my Dewalt pilot point bits I was melting more than I was cutting. I need these holes to be pristine and clean.

I am using my CNC machine for the drilling. I have the proper end mill cutters for the other tasks I need to perform. I just need the correct drill bit. I would the hole to be close to 2mm (approx 5/64").

Do you think I should set my tool path to 'peck drill' or just go straight through?

Thanx,

shotgunn

[Gene Howe]

Here ya go.

http://www.preferred-industrial.com/aluminum-drill-bits.html

[Michael Dunn]

Thanx!!! Any other links are still welcome too. I put in a request for a quote.

[Paul Ryan]

Michael any high speed steel, titanium, or cobalt twist bit will do just fine in aluminum. Aluminum is really soft an drills easy but you need to slow down your drill 500 rpms is plenty you could even go slower. Brad point bits wont work so well you just need a ordinary twist bit. If you have center punch give yourself a dimple to start with and go for it. 5/64 that is small enough you wont have to drill a smaller pilot hole 1st.

[Keith Westfall]

For really nice holes (if the thickness allows) use a step drill. Finish lightly from both side and there is a really nice chamfer on each side of the hole.

[Don Alexander]

i found that Bosch titanium coated regular tipbits cut thru aluminum like butter and the last one i bought i got at HD for a reasonable price

[Rob Hermann]

When I worked in a metal shop years ago, we used regular highspeed steel drills, sharpened like normal and then did what the olds guys called "break the edge". Just flattened the sharp cutting edge ever so slightly at 90 degrees to the drill. We drilled a lot of alum, brass and bronze that way.

[Paul Janders]

Keith-
Great tip. Thanks!

[Rob Cunningham]

You should set the machine to peck drill if you are going through 3/4" aluminum.
Are you using any coolant and what is your feed rate?
Also, use a center drill to spot the holes first or the drill bit will wander when entering the material.
HSS drill bits work fine in aluminum.