Quote Originally Posted by Peter Griffin View Post
Hello Everybody I found your (Our) site about a week a go and have just registered. I am looking to build a cnc mill capable of machining Ali/Brass:wave:
Welcome Peter.
Can you be clearer about your goal?

Sorry if you know all this already, but here are some thoughts you might find useful.

Do you mean a router, or a true mill? Generally with a router the cutting head moves in X/Y/Z and the workpiece remains stationary, which is good for large wood/plastic/foam items. In a mill the cutter moves in Z, but the workpiece moves in X & Y, whcih is better for smaller items, particularly metal ones. Obviously there are cross-overs between these.

For cutting metal (with any reasonable speed or depth of cut and accuracy) you need rigidity which is generally hard to achieve with a router arrangement without incurring a lot of hassle and cost. A true mill is characteristed by a lot of mass in a big casting to give the rigidity, and therefore most CNC milling is done by converting a conventional off-the-shelf mill rather than building from scratch (although I have seen some ground-up builds based on a lump of steel girder). This is likely to be the cheaper route overall as well.