I am super new to cnc machining and I have no one to teach me/to let me know when I'm doing something totally wrong.
Ok, so far I've machines cheap plywood and g10, and recently I've been trying to work on copper and aluminum, though I have yet to actually try aluminum.
I don't have proper work holding or any cooling system set up, I'm just working with what I have at the moment. I started out using 1/16 flat end mill from carbide 3d, had my feeds and speeds fairly slow, and sat next to my machine through out the run spraying it with a jet of water from a bottle every 10 seconds or so. This actually worked for a bid, but it chewed up the copper in a funny way and after a while it just didn't even work anymore. I lowered the speed, tightened all parts of my machine, but I still had issues.
The past two days I've been using a 1/8 inch ball nose endmill (from carbide 3d) and using super slow speeds, this morning I had it working, I was still sitting there with water the whole time, but it worked, though it still ocassionally shuttered. I changed the feeds and speeds/etc to be even slower and at this moment, I have it running without me squirting it, and without the shuttering.
I think the water actually caused the tiny flakes to stick around and clump up, and I think going slow enough with this non ferrous metal its stays cool enough and heat is not a problem. (especially because copper conducts so well, I imagine a lot of the heat disperses quickly.)
Feedrate: 2 in/minute
Plungerate: 0.5 in/minute
Depth Per Pass: 0.008 in
Also, I've found that setting the retract height to 4mm saves a lot of time, and with my setup/design that's plenty of room.
pictures to show the funky copper work I'm doing, and the horrible method of work holding I use.
I'll be messing around with different methods of workholding soon.