The best tool I have found that works on 3-D printed parts is the Xuron photo etch cutter. Very long narrow blades to get in tight spaces. Seems to make cleaner cut with less stress on the piece. I have a very high “survival” rate of parts using those. Other items I have tried, like photo etch saw blades with very fine teeth work, but are much slower and due to the blade size, way less versatile to get into awkward areas on the print tray.

I wrote to the “new” group taking over the old Shapeways franchise. Very nice response but it sounded like they were a long way from opening up shop for ordering. Their first focus is offering 3-D printing services, not a marketplace for people to buy printed items. I have several wants as well, and was caught in the closeup of Shapeways.