Drilling copper fail..

[daleyd]

I’ve drilled hundreds if not thousands of holes in copper busbar - generally with battery hand drill and never had an issue? Never ground drills any particular way, generally just used what came out of the box. I haven’t used particularly high or low speed, just fairly standard speeds that you’d use for steel seem to have worked for me - though I do find lighter pressure is needed. A quick squirt of wd 40 or something similar for lube, and quite often nothing at all (generally done on site so it’s whatever you I’ve to hand)

The worst I had was enlarging some holes in some flexible busbar (multi leaves of thin copper in a bus bar shape) - I tried to do them all in one but they just grabbed so ended up separating the leaves out and doing each one individually. That was genuinely soul destroying…

 

[jimbo84]

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Skimmed, semi or full fat

 

[Pete.]

Skimmed, semi or full fat

There was only full fat in those days

 

[tom2207]

regrinding the end of a twist drill to look like a wood spade bit is best I can describe it.

ah , I often grind them to nearly flat , like an end mill for certain jobs , like cleaning the bottom of blind holes on things like brake slide pins , . many thanks for the reply.

 

[Guineafowl]

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Milk is an emulsion of fat and water, so would soluble oil be the modern alternative?

 

[MetalMonkey]

For thick stuff like that I'd peck at it, shouldn't be too bad.
Drilling thin copper sheet is a nightmare, but I've had reasonable success sandwiching it between two bits of wood.

 

[tom2207]

Milk is an emulsion of fat and water, so would soluble oil be the modern alternative?

not on corn flakes ,

 

[Guineafowl]

not on corn flakes ,

But better than skimmed milk.