A simple wedge can be very persuasive
Around Christmastime, my lathe becomes a production platform for platters. After trying most of the options for mounting a workpiece to a faceplate, I've decided double-faced turner's tape (Rockler part no. 25801, $19.95; 800-279-4441, rockler.com) is as close to perfect as it gets. Sometimes, it works too well: I usually have to chisel off the sacrificial faceplate and often mar the underside of the platter.
For a solution, I made a sacrificial faceplate as usual, but I cut a 1/2" dado 9/16" deep through the center before bandsawing it round and screwing it to the lathe's faceplate with the dado facing out. Next, I make a small hardwood wedge that fits into the slot. Then, I use turner's tape to mount the workpiece to the sacrificial faceplate, and turn the platter.
When I'm done, I insert a thin piece of veneer (to protect the workpiece) and the wedge into the dado gap and gently tap in the wedge until the workpiece pops off.
-- Doug Green, Marble Falls, Texas