Here’s one of my favorite tricks:
We use disks of artist’s mat board (a heavy cardboard) and
bookbinder’s board (thicker) in a couple of ways.
To make the disks:
I cut a square of board, say 2 inches, then put a hole in the center
and put it on a flexshaft mandrill usually used for sanding disks or
rubber wheels. I use the ones with the oversized screw and 3/32"
shank (again Rio sells them.) Then, VERY CAREFULLY in the handpiece
with the flexshaft running slow, hold a knife against it describing
a circle as it turns, cutting through to form a disk, your choice 1
inch, 2 inch, up to 3 inches. You can also precut it with scissors
instead. Then with the flexshaft running slow again hold the edge
against 180 grit sandpaper to smooth and true it.
The resulting disks on a mandrill can be used with your flexshaft in
the following ways:
Put on self stick 3m micron graded sandpaper (kind of a plastic
sandpaper from Rio Grande) one side or both sides to use as a big,
rigid, sanding disk. I put a different grit on each side. Replace
the sandpaper when it is worn out. I use these for sanding the edges
of rings, backs of pendants etc where larger reach is desired. This
sandpaper is great for platinum, so we keep a set reserved for that
use. I use the various grits to shape and sharpen gravers.
Leave off the sandpaper, put on bobbing compound, Tripoli or Rouge
and use them as tiny lap polishers. Thinner types of cardboard are
used in this way to polish in tight spaces.
You can even cut a slit or two with a sawblade and use them as split
lap polishers (they require EXTRA CARE and don’t last as long this
Scraps from the mat board and odd size pieces of self stick
sandpaper can be used to make little shapes as sanding sticks to get
into tight or oddly shaped spaces.
From our newest jeweler, Andrew Elmgren, comes this tip which solves
an annoying problem.
Felt covered wooden inside ring polishing mandrils are sometimes
difficult to break in for the tapered spindle polisher motor. My
usual technique is to use the steamer on the inside, thread them on
the spindle and let them dry, but I was having trouble with the
Andrew’s suggestion: Ream out the hole and fill it with warm Jet-Set
(Rio Grande) then thread it on the tapered spindle and let it cool.
Thread it off, on, off, works like a dream!!