Drilling 3/4" ACX Plywood

[IlanDeiStudio]

Looking to get recommendations on drilling 1/2" diameter holes through a 3/4" plywood.

Need to determine both speed and feed rates as well as the proper bits to be using. I would prefer to use a 1/2" diameter bit.

Spindle is a 5 hp columbo with max rpm of 24000

Any recommendations would be helpful. Searching around I have found little information on the subject.

[bleeth]

Try spinning about 8k and punching at .5. Upcut is best but ACX will likely have some tearout at the top. Up or down cutter use a peck with getting the bit out of the material one time about halfway through to clear the chips. Keep a close eye out for too much heat. It is the biggest issue with drilling on a cnc. Fires have been started that way. Lots of the time it is better to use a 3/8 and inside profile or clear with a 3/8 stepdown. Still will go pretty quickly.

[IlanDeiStudio]

Thanks Dave worked pretty well. Had a little bit of tear out at the top but mostly due to the nature of the material.

[bleeth]

You're welcome Ilan.
Glad it got you going.

[mcmark]

It might help to use a 1/2 brad pointed bit.