I milled thin copper sheet into spacers for my knife handles. Here is a time lapse of 1 mm copper sheet being milled. 3 mm/sec, 0.25 DOC, 1/8th inch bit. . The material was held down with painters tape and super glue. I ended up with 5 x 1 mm thick and the 2 x 1/8th in or 3.125 mm spacers are milling now.
Instagram is hosting the timelapse.