Tumbling - metal vs plastic shot

I’m considering a smal l vibratory tumbler (Raytech TV-5) but it only
accommodates plastic media, not metal shot. I’m pretty new to this,
and have never even used a tumbler, having just hand finished my
projects. When do you use metal vs plastic media? Will I regret not
having the capacity to use metal at some point? I want a small
tumbler since I’ll only be doing one or two things at a time. So
far, I thought I might use one to remove the bits of investment stuck
to my pieces (I’m the one who wrote not long ago about rock hard
investment), removing the pinkish cast from brass after pickling,
maybe some rock tumbling, and of course polishing. Price is of
course a consideration, but I don’t want to find out in a few months
that I should have spent a bit more on a different machine if that is
what I really need. Is there an advantage other than shorter time
using a vibratory vs rotary? I do need to learn a lot more, and would
appreciate a couple of book suggestions as well that explain in
greater depth the finishing process.

Thanking you all in advance.
Peggy

... would appreciate a couple of book suggestions 

Orchid member Judy Hoch wrote a book packed with It is
available from Rio Grande, Otto Frei, and Gesswein:

http://www.ganoksin.com/gnkurl/ep814d
http://www.ganoksin.com/gnkurl/ep814e
http://www.ganoksin.com/gnkurl/ep814f

Neil A.

Peggy- I fear that if you put a piece in the tumbler with investment
on it the tumbler would hammer the investment into the metal thus
leaving it with dents or pits. Or it could dissolve the investment in
the tumbling solution and abrade the metals.

I’m just guessing here.

Judy Hoch should know.

Have fun and make lots of jewelry.

Jo Haemer
timothywgreen.com

Hi Peggy,

I’m by no means a seasoned veteran at this but I have learned a
little about tumblers. I do some silver smithing and I cut and
polish my own stones. I have the smallest available rotary tumbler
which is filled with stainless shot. I also have the Raytech
vibratory tumbler you are considering, filled with ceramic media. I
use the rotary for my metal work. The stainless shot does a good job
of debriding, polishing, and work hardening. I use the vibratory
tumbler for polishing stones, which it does far quicker than the
rotary and does not change the shape of the stone. A serious
consideration is whether or not you need tumbling to work harden
your pieces because the vibratory tumbler does not work harden. I do
a lot of chainmaille and I needed polishing and work hardening -
which the stainless shot does in no time at all!! Go the extra money
to get STAINLESS shot because it doesn’t rust! Hope this helps a bit!

Rhonda

different reasons. I can’t help you with type of tumbler as I use
the rotating style with barrels that can be rinsed after each
process. I use plastic for cleaning, deburring, and refining with
grit gradients. Then stainless shot for polishing.

Ruth Mary

Hello Peggy,

First, let me recommend that you purchase Judy Hoch’s little book
"Tumble Finishing for Handmade Jewelry." Modest cost and available at
Rio Grande among other suppliers. This has been discussed frequently
in the past, so a search of the Orchid archives would be of benefit.

Second, you should consider having both a rotary tumbler and a
vibratory tumbler. I have two small rotary tumblers and use them wet
with stainless media. They can also be used dry. My vibratory
tumblers are both used dry. One is loaded with crushed walnut shell
and the other with a mixed media for final polishing.

The rotary tumblers can be purchased inexpensively if you get the
kind sold to kids for polishing rocks. Vibratory tumblers can be
purchased from reloader suppliers. They’re used to polish brass
casings. What you will find out is that the media can be more
expensive than the machines!

NOW, order the book and read it. They reconsider your questions in
light of you new-found knowledge. Having a better idea of what you
can expect from using a tumbler will help you decide how to proceed.

Judy in Kansas, where the temp was 2 degrees F when I got up and has
risen all of 9 degrees be late afternoon. Hoping for a warmer
tomorrow!

Thanks to those who pointed out that the vibe tumbler does not work
harden silver whereas the drum tumbler does. Does everyone agree on
this?

As a cheap alternative to the Raytech and other name brands, I
bought a Harbor Freight vibe tumbler. Like a lot of their products,
it needed tweaks and work arounds. Took the bottom off and had to
grind off a small part of the weight to allow a full measure of
adjustment (for more or less vibration). Someone on a rock tumbling
list pointed out that the bowls on these HF tumblers are thin and
will wear through quickly, but another person reported using the
spray-on truck bed liner (about $10 a can) to line the bowl and beef
up the thickness.

I haven’t used this enough to know whether it will last long enough
to justify the price (maybe half what the name brands cost?), but it
was an easy entry into vibe tumbling for cabs. Extra bowl was cheap,
too, and came filled with walnut shell for about $10. YMMV.

I absolutely disagree that a vibratory tumbler does not work harden
silver.

I usually make earrings with.8mm sterling hooks and once I have
soldered these they are dead soft. To harden them I then hammer the
top of the loop to slightly flatten and harden it and then give it 2
hours in my GyRoc vibratory tumbler in stainless steel shot mixture
(pins, cones and balls) in burnishing compound (or a few drops of
dishwashing liquid in water) to burnish and to work harden the hooks.
They go in dead soft and come out springy.

I don’t use a rotary tumbler for this for the reason that others
have indicated, that finishing in a vibratory tumbler has much less
tendency to round over the corners of your work

All the best
Jenifer Gow
Tears of the Moon Artisan Jewellery

As to the question of tumbling to remove investment - while the
action might remove some investment, Jo Haemer is right on - the mess
would be in your work pieces. As cast metal is annealed, thus softer,
and the one thing you want in tumbling is a clean solution with
graded abrasives. Investment lumps would create a new definition for
abraded and abused metals. FWIW Judy Hoch

Hi Judy,

I’ve done that (tumbled to remove investment) but in a magnetic pin
spinner, rather than a barrel tumbler.

The cycle time was a few minutes. Just enough to pound off most of
the loose crap. The goal was not to have to find my earmuffs before
lighting up the air compressor to power the blaster. Seemed to work
just fine. Didn’t do anything noticeable to the sterling castings,
beyond burnish them lightly.

I definitely got better results with the pin spinner, due to the
small size of the pins, and their ability to get into small areas
between the sprues, than I have with full sized barrel shot.

FWIW.
Brian

Brian’s right - and sorry I didn’t mention it - many casters use
magnetic pin finishing equipment to get rid of investment - it works
a treat and because most magnetic pin finishing equipment works
quickly and with very little impingement, it is terrific for this
application. The note is - effective pin finishers are fairly
expensive. Judy Hoch

The note is - effective pin finishers are fairly expensive. 

Judy, have you had a chance to compare commercial pin finishers to
home-brew solutions? I am actually pretty happy with my machine, but
have no idea how what I miss.

I have used several commercial pin finishers. IMHO the bigger they
are, the better they work. I don’t see why homebrew ones wouldn’t
work as well, but I’ve never built one or tried one.

I really do try to check out tumblers, but if they are not
commercially available, it doesn’t work for me. Sorry.

Judy Hoch