Nice to see someone else trying to do another Xjinn block! I made one with aluminum and it was STILL a pain.
The drill press that I used was very similar and I noticed that the stage holding the block was not very stable. Any pressure at all and it flexed downwards, causing lateral pressure on the drill bit. I heard a lot of "ping" noises until I learned to do it really slowly.
Also, when working with aluminum, WD-40 really is a good cutting oil! All the machinists here at work swear by it. It was supposed to have been designed (in WWII) as a cutting oil for aluminum. As for working with copper, I don't know if there are better substances. When working with steel, there are cutting oils with sulfur compounds that help lubricate, but those same sulfur compounds do not work well with aluminum machining. If you are looking for cheap, one of the machinists here suggested that I use diesel. It's not easily flammable (which is why diesel engines use wierd combustion methods), it helps lubricate well, and it's very cheap.
I second the person who recommended using different drill bits for copper. You want an incident face angle that is much less agressive! This is because a normal drill bit cutting face is angled to cut into the material and shave slivers off. With copper, it is so ductile that if the drill bit actually bites into the copper, it will snap off any small drill bit quite quickly. You want a zero or negative angle so that you (lightly) press into the material to get any cutting action at all (hard to describe).
Note, this is all what I've been told by the machinists at work. I don't do this stuff for a living.
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