Soldermask, and through hole vias for that matter. I've used an Othermill. Absolutely fantastic piece of kit, it's saved me a lot of grief. But making SMD work

Soldermask, and through hole vias for that matter. I've used an Othermill. Absolutely fantastic piece of kit, it's saved me a lot of grief. But making SMD work is out of the question. (Yes, you can get a 1206 to work with the Othermill. No, you aren't going to get a QFN16 with an exposed pad to work. Or for that matter, a QFP16. Or even an SOIC16.)