Yes! The MicroMill can cut almost all materials that are softer than steel. If you want to engrave a piece of aluminium, cut keyring out of brass or any combination of the two you'll be absolutely fine.
As a general rule, use the biggest cutter you can and take things nice and slow. We'll be including cutters and a Feeds&Speeds guide with each machine to get you started!
If you're looking for a machine to do any work with stainless steel, titanium, iron, etc - these cannot be cut on the MicroMill and we dont recommend you try. Perhaps use the MicroMill to cut your parts from softer materials like aluminium or Delrin before outsourcing them in stainless?