You beat me to it John. I've got a few things on the go right now, but just passing on some copper specific tips from my (limited) experience. It can be very grabby material on conventionally ground drills. Similar issues I was having on brass. I have since dedicated a drill set to 'dubbed' tips that I use on brass & bronze, just dress them as I need them. I would expect they would do better on copper too , but haven't tried yet. WD40 works well as a cutting/tapping fluid. I had to make some 'hammer head' soldering tips back in the days we built our own end-to-end NICD & NIMH packs & those were copper. I don't recall what alloy, it was Metal Supermarket stuff.