I’d be a filthy liar if I said I got this right on my first try, but I made this brass pendant for my wife for Mother’s Day (I drew 3 stylized glyphs to represent each of our kids to engrave on it). MPCNC handled the brass with no issues! At one point I was doing 1mm depth of cut at 3mm/s, and it just glided through.
I started with a 5mm thick piece of brass flat stock. Milled it down to 2.6mm with an 1/8" end mill at 25% step over, 1mm depth of cut at 3mm/s. Took it down to 2.5mm with the same tool, 0.1mm depth of cut at 6mm/s with 5% step over. Did a spring pass at 6mm/s with 5% step over.
The engraving itself was done with a 0.2mm 20degree v-bit at 3mm/s, 0.3mm depth.
The cutout was done with an 1/8" end mill, 0.3mm depth of cut at 1mm/s.
I broke it free from the flat stock and broke the edges and hand finished with a dremel. I went at it aggressively with 1000 grit sandpaper. Dropped it in some solvent to clean it up and called it done.