There are many different abrasive materials available and I’ve read
the catalogue descriptions. I still don’t understand what the real
differences between them are, as they all sound like they do the same
things. I would appreciate feedback on which abrasive experienced
jewelers use for what purpose. I am particularly interested in
cleaning out the inside of rings that have been sized up. Cost
effectiveness is also an issue as I size up about 40 rings each day.
I’ve used the aluminum oxide cartridges, but they “blow apart”,
rather than wear down, once or twice a week. The guys in the shop
all use these. They don’t use the sanding bands, saying they have
the same “flying apart” problem.
The trizact bands barely lasted through 1 ring before becoming
uselessly dull. I tried these with and without Stuller’s lube.
The 3m Imperial micro-finishing film is great for use on a sanding
stick, but wears out too quickly in the small bands.
I love the 3m flex diamond bands, but they’re really expensive. The
other band abrasives I’m aware of include: Silicone carbide, 3m
Cubitron ceramic (Purple), 3m Trizac CF (Green), and 3m Diamond
microfinishing bands. I thank you in advance for your feedback on
what abrasives you use, and those you don’t care for.
There are many different abrasive materials available and I've
read the catalogue descriptions. I still don't understand what the
real differences between them are,
Joasona - another question that has as many answers as people… We
use the wooden mandrels that go on a tapered spindle and take 1/3
sheet of sandpaper, or in our case almost always emery paper. Since I
couldn’t find any new ones that had straight shafts, as the tapered
shafts cause the sandpaper to come off, I made a few on the lathe out
of aluminum rod. They have a split down the shaft to hold sandpaper,
and are about 4" long. Use a rubber band to hold the sandpaper on. We
use them to sand the inside AND the outsides of rings. It’s cheap -
uses any regular sandpaper - and has a large surface area. As for
abrasives, we use emery paper exclusively, as does most of the
industry. Emery is naturally occuring aluminum oxide, of course.
Carborundum is much too aggressive, though we’ll use it for some
other project - wood, steel, whatever, at times. Large (like 6")
Cratex wheels work really good on the outsides of rings, but I never
liked the inside ring sticks they make, and they suffer from the
grooving issues that grinding wheels can have… We don’t sand
rings with a flex shaft except for detailing - life is too short.
I never did like abrasive bands, debris all over, mostly in my face,
yuk.
For heavy cutting try an inside ring bur. They come in various cuts
and configurations. With any kind of abrasive grit you’ve got to use
several grades of coarseness. Step 1, step 2 and so forth. With a
sharp bur, by altering the pressure you can get succesively smoother
finish, greatly reducing bur changes.
I have some cylinder shape rubber wheels in a coupla compounds, I
believe I got em at Rio. With a rapid back and forth motion(like
honing a car engine cylinder) they will wear pretty evenly and give a
decent finish.
I also don’t like a ring buff for the baldor. Its OK but usually
leaves small concentric grooves. I get rid of these by using a 7/8"
white brush on the flexshaft and polish across the lines
With a rapid back and forth motion (like honing a car engine
cylinder) they will wear pretty evenly and give a decent finish.
Yeah, always a good idea to relate a new activity to one everyone
has experienced! Thanks for the laugh! Now, if you explained how to
“hone a car engine cylinder” by relating it to jewelry making, that
I might be able to follow… :>]
Noel
I to size about 30 to 40 rings a day. I use a larger Ball bur for
taking the metal down quickly only on rings that I have sized up. I
do all up size rings with this at the same time. I have found that
the Cartridge rolls medium grade are the best and I buy a gross at a
time. There Cheap. Then I finish the inside and out with a brown
rubber wheel before polishing. I am a contract Jeweler and time is
money. Are you a contractor?Working at the Bench for 27 years, I have
came up with the fastesd production process. Any questions please
E-mail me off line.
Thanks Johneric
Yeah, always a good idea to relate a new activity to one everyone
has experienced! Thanks for the laugh! Now, if you explained how
to "hone a car engine cylinder" by relating it to jewelry making,
that I might be able to follow... :]
Sorry, I thought everyone built racing engines in their spare time!
http://tinyurl.com/2ewnzz
Hope that link worked. Second picture down shows the crosshatch
pattern you get from the back and forth motion I described. While you
don’t need to get micro-mechanical about it, it does get rid of those
nasty circumferential grooves. I might liken it to hand lapping a
flat
stock. If you sand only in one direction ( ),even if you switch
directions at each successive grit, you often get a few stubborn
grooves. Use a circular motion and magically there are no(or very
very few) grooves.
I dunno, that probably isn’t very clear. But take some scrap and try
it out, hopefully you’ll see what I mean.