Peter:
Good Luck with your new Graves polisher!! I have something very
similar, but not by Graves, older, same range of grits.
Advantages: portable, fairly quiet, can use while watching TV,
conversing. Not real messy like belts with water spray — use
one of those in the house and you’ll have dust everywhere. A
great polish on items that require or allow diamond, and really
good for materials which undercut. Got the best polish ever on
Lapis Lazuli this way! Great also for touching up scratched
cabs, maybe while still in the settings.
Disadvantages: some things polish better with oxides. Running
thru all those grits and making sure you hit every spot (have to
keep the stone twirling and go every which way with it) is
tiring, especially with large stones. Easy to end up with a good
polish but flat spots or a poor outline. The curves are much
easier on rubber drums or pads with some give (the drums are
better than the pads, I think). If you preform on grinding
wheels only (e.g., silicon carbide 100 and 220), no belts, you
will be spending a lot of time on your 325 grit to get the
grinding scratches out. I hate to be a party pooper, but for a
lot of cabbing, grinding wheels and belts, 6" or 8", or diamond
wheels if you have the cash, make the whole process much easier.
I would have thought that it was easy to contaminate the spools,
but never had that problem, just make sure you put the right grit
on the right wheel, might mark below them, I had a lot of
different grits and could never remember whether to use 8000 or
14000, etc. Once it’s on there (too coarse a grit for the wheel)
you won’t get it off. You can buy the loose grits and mix them
up, put them in syringes. You can use lipstick as a medium, it
sticks better than oil. With small stones and a lot of patience,
this rig makes nice small cabs, will do corundum nicely, I would
think, also jade, and all those composites which undercut on
other cutting surfaces, like rubber. Enjoy, and if you go on to
a more elaborate machine, E-mail me, I’ve built one and hav
plans for others. Also check Hale Sweeney’s Lapidary sight, I’ve
never been there, but my faceting buddies say it’s great.
HTH,
Roy (Jess)