1. The reason the snap-on discs don’t work is that the square mandrel that is compatible with the discs’ brass center mounting area does not allow enough clearance to mount two discs.

2. Classic screw mandrels allow you to stack two center-punched sanding discs face-to-face on the mandrel. It’s a good idea to start with a coarse grit to remove metal quickly.

3. Insert the screw through the pinholes on both discs (these are Adalox aluminum oxide discs) and insert the screw into the mandrel.

4. Tighten the screw so the discs are securely mounted and take care to not lose the miniature washer that protects the disc’s backing paper from tearing.

5. To abrade wire, insert the wire tip between the discs and run the motor at a slow-to-moderate speed. I brace my handpiece on my bench pin to keep it flat and steady, which makes holding the pinstem wire perpendicular to the sanding discs much easier.

6. Once you have created a symmetrically pointed tip on the wire, switch to a finer abrasive grit.

7. This process is much faster and more efficient than hand-filing a taper in the wire and then sanding it, and I find the wire is less likely to bend as I do so. Progressing through finer grits of paper and then polishing the wire creates a sharp, smooth, and beautiful pinstem in a fraction of the time it takes by hand.

I also use this sanding method to thin the ends of tabs and wire prongs when creating cold-connected settings and parts. Slightly thinning or tapering the metal makes it much easier to push those tabs or prongs against whatever object I am mounting in the piece.