Summary

--Here's a way to mount a flex shaft tool to do sanding with both hands free to hold the work. Attach the disk adapter to the business end of a 2 in. sanding disk with some rubber cement. The disk mandrel then goes into the chuck and a peel-and-stick 3 in. diameter sanding disk can be applied.
--The table is designed so that it can be added or removed without tools: the four mounting points have 'keyholes' that hook on four protruding M4 button head cap screws that are fastened to the pedestal..
2021_02_11:
-Uploaded Sander_Disk_Adapter_04; this has a 3mm center hole and will fit a standard cutting disk mandrel. There's a recess on the front side that's big enough to get a socket in it to tighten the retaining nut. The cutout is small enough to be printed without support.
2021_02_13:
-Tossed all the earlier versions and
-Uploaded Sander_Disk_Adapter_05 which is a little more refined.
-Uploaded Sander_Table_02 which has better clearance allowing it to be installed or removed without interfering with the sanding disk.
2021_02_12:
-I've redesigned the table to make it easier to attach with more clearance for the barrel of the handpiece. I've lengthened it a bit too.
Uploaded: Sander_Table_02
2021_02_25:
-Replaced Sander_Disk_Adapter_o5 with _06 which will keep the mandrel attachment nut from coming loose.