If you try to hand feed brass into a milling bit you will certainly lose at least one finger. The workpiece will either fly out at high speed or catch on the bit and become a whirling fan blade. I bought a micro mill/drill from Harbor Freight Tools a couple years ago. I was about $200 plus a few accesories, but it cuts slots wonderfully and is relatively small. You are limited to pieces smaller than 4x6 inches. And it doesn't cut hardened steel.