Need Help!- Machining copper

[engelskmannen]

Hi all, I'm soon going to machining various components made of copper using my Hitachi Seiki "super hicell" machine.
I have no experience in machining copper so am hoping someone out there can suggest some cutting speeds and feeds for milling, turning and drilling - Please...

Thanks, Engelskmannen

[Geof]

This topic comes up periodically did you try a search using the custom search box for CNCzone just above the title line at the right.

Copper can be a real pain to machine and how it behaves depends on whether it is work hardened or completely soft. My experience is really sharp tools with a good top rake, grind your own using HSS. Inserts carbides do not work very well although if you used the micrograin highly polished uncoated type intended for aluminum it may be successful; Iscar has them but I forget the part number (sorry).

A cutting fluid/lubricant is also essential in my experience and something like kerosene can work, also I have used lubricants intended for tapping.

Use the same speeds you would for mild steel with soft copper, maybe even slower, but for work hardened copper you may be able to go faster. Take small cuts and a slow feed and increase these if things seem to be going okay.

Good luck.

[RICHARD ZASTROW]

FWIW Don't laugh but I've used vegetable oil spray "pam" as a coolant/lubricant to machine soft copper.

This was with a PCD, (polycrystalline diamond) insert on a lathe. May possibly discolor the copper though.


Dick Z

[engelskmannen]

Many thanks for the tips Gents, I've ordered some D and V geometry, polished turning inserts for aluminium and a "special for aluminium" 25mm dia, single insert mill from Iscar today.

Cheers, engelskmannen