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.