Thread: Drilling Copper

What is the best way to drill 3mm & 4mm copper plate without it catching, holes are 1/4" up to 1" .

Putting a neutral rake on the cutting edges would probably help with the grabbing, it works in brass.

Clicksprings shows how to do it for brass...i reckon it would be the same for copper

If the material is only thin, a shallower drill point angle will also help (135 degrees or even more if you can do it. You really need to get the tips cutting before the point breaks through.
I've been told that milk is a good cutting fluid for copper. Never tried it (maybe one day )

Michael

I would think a stepped drill bit would work. They work beautifully on sheet that is too thin to use twist drills on. For 4mm sheet you might need to come in from both sides. I have some copper sheet. Never tried drilling it though. Let me know if you want me to try it.

Stepped drill bits work well on soft thin materials as the rake is pretty neutral. Just don't use one of the style with a helix in the flutes.
A center drill might be an option for smaller holes or just put a tiny zero/reduced rake on the cutting edge of your drill with a diamond stone.
I'd use holesaws for the larger sizes.

Steve

Being a soft material, you could try a Forstner bit forstner bits.jpg as used for wood, I know they work on aluminium OK. When the point just breaks out the other side, turn the piece over and drill from the other side.
I used Inox spray as a lubricant.
If a particular odd size is required, they can be ground down to suit. I did mine with a flap disc on a 4" grinder on my Drill Press, just make sure the cutting side is larger than the shaft side, I had about .5mm clearance.
I've found using a hole saw, sometimes leaves markings around the edge until it starts cutting.
Kryn

Originally Posted by KBs PensNmore

.....
I've found using a hole saw, sometimes leaves markings around the edge until it starts cutting.
Kryn

Masking tape on the surface of the part or drilling through a sacrificial part (or use one with pre-drilled hole) clamped on top of the actual part can help with that.

Steve

A brad point drill or a spade bit works ok, on sheet.

Grahame