We've had very good success with an extremely trivial hold-down system for milling PCB's: 3M transfer tape (otherwise known as "gummy back"). This is an adhesive tape that is pure adhesive only - no substrate / carrier. Our transfer tape is 2" wide. Simply run a strip or two down the backside of the PCB and stick it in place. The tape "rolls" off easily after the finished PCB has been pried up from the deck of the machine. Takes a lot of effort to get the PCB up and off but that's the price we pay for ensuring that the board stays flat while milling. dwayne PS - again, this is on my buddy Ryan's machine. I'm slowly building an equivalent system (sort of) for myself. dwayne At 09:53 AM 12/17/2007, Timothy Weber wrote: >For instance, I've heard that really effective hold-down systems for PCB >board are not trivial. I don't want a new project called "design and >make a board fixture"; -- Dwayne Reid Trinity Electronics Systems Ltd Edmonton, AB, CANADA (780) 489-3199 voice (780) 487-6397 fax www.trinity-electronics.com Custom Electronics Design and Manufacturing -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist