ShopBot Buddy milling 16 gauge aluminum sheet using denatured alcohol in fogbuster as coolant. 108 ipm, 0.002" ipt, 18,000 rpm, three flute 0.25" coated endmill. The denatured alcohol has worked well. No residue. Part remains cold to the touch despite the chips being hot. After several hours of milling we've only used about a half inch of coolant. Mist is barely perceivable. Only a few drops per minute.