If I were going to get a new tumbler, I'd get the same thing
again. I'd stay away from the rotary tumblers. 1st off they're
slower than the vibratory, it takes a vibratory about 1/2 hour for
a good finish, longer won't hurt, but isn't necessary. 2nd, There's
no lid to leak or belts to replace. They're just a whole lot easier
& more reliable than rotary tumblers.
I'd like to respectfully disagree with Dave Arens - when using
steel, there is no difference in the time between vibratory and
rotary machines. When using abrasive media, the vibratory is about
three times faster. I find that I get a very good finish with steel
in a rotary tumbler in thirty minutes.
Porcelain media comes in two flavors - abrasive and smooth for
polishing. Usually the abrasive media is little cylinders and has a
rating for what kind of finish you can achieve. This stuff is used
just like any other abrasive media.
The polishing media comes in little spheres. There are two very
important guidelines to polishing with it. First, you really need
more than one size of sphere. The second guideline is critical to
getting a good polish. The new media must be conditioned for a
substantial period. To condition porcelain spheres, load your closed
system vibratory tumbler with your polishing media, add five to ten
percent by volume of silver pieces. I typically use fused or cast
pieces. Add water and run for five days. Check periodically to make
sure that the tumbler hasn't gone dry. I use about one fourth volume
of water of the tumbler capacity. For example if you have a five
quart tumbler, you need about a quart of water.
When your five days of conditioning is done, you will discover the
most wretched dirty mess. You will curse me. Separate the metal from
the media. Wash the media in soapy water. Use your ultrasonic on the
metal to get the gunk out of the crevices. The media will be kind of
grey and forever after will polish beautifully. It is substantially
cheaper than stainless steel and IMHO works far better than steel in
a vibratory tumbler. You certainly could condition with gold, but
silver works just fine for conditioning and it doesn't matter what
metal you run after conditioning the media.
Vibratory and rotary tumblers both have a place in mass finishing.
I've had this particular rotary tumbler for 12 years, maybe more, and
it has worked flawlessly. It's fairly large because I often tumble a
batch of anticclastic cuff bracelets in it. If you do big stuff, your
tumbler, whether rotary or vibratory, needs to have enough space for
your work to tumble freely.