What is the difference between a tumbler and a vibrator polisher?
Is one more effective than the other? Is a vibrator polisher likely
to run more quietly?
Also, does anyone know where I could find instructions on how to
make a either of these?
thanks
Hi,
What is the difference between a tumbler and a vibrator polisher? Is one more effective than the other? Is a vibrator polisher likely to run more quietly?
The basic difference between a vibratory & a rotary tumbler is the
way the unit is driven.
A rotary tumbler is a barrel with 2 closed ends. The items to be
tumbled are put in the barrel along with the polishing media. The
media can be steel shot, ceramic cubes & other shapes, silicon
carbide grit, crushed walnut shells with imbedded rouge or other
material & other things. The barrel is placed on rollers with at
least 1 of the rollers turning causing the barrel to revolve. As the
barrel revolves, the stuff inside it forms a hill against the side
of the barrel. As it reaches the top of the hill, it slides down to
the bottom. While sliding, the media impinges on the items polishing
them. It should be noted that the only time polishing is taking place
is while the items are in aprox the top 1 inch of the slope sliding
down from the top to the bottom. If they’re not in this layer,
they’re just along for the ride.
Depending on what’s being tumbled & the desired finish, tumbling
times can go from hours to weeks.
The vibratory tumbler consists of a bowl that sort of resembles an
angel food cake pan with a rounded bottom. The bowl is mounted on a
spring mounted platform to allow motion in all directions. A motor is
usually mounted to the bottom side of the bowl platform. The motor
has a weight attached to it’s shaft. The weight causes an out of
balance condition when the motor runs. The out of balance condition
cause the platform & bowl to vibrate.
The same media used in the rotary tumblers can be used in the
vibratory tumblers. The items to be polished are placed in the bowl
with the media. When the machine is turned on, everything, bowl,
media & items are vibrated. The vibration causes the bowl contents to
rotate around the bowl in two directions, one from the outside to the
inside & the other parallel to the circumference of the bowl. The
polishing action is taking place 100% of the time to all the items in
the tumbler.
Time wise, the vibratory tumbler is faster than the rotary & since
everything is in a bowl, leaks & blowouts aren’t a problem as they
can be on a rotary.
I haven’t seen any noise figures for any tumblers, rotary or
vibratory, but I’d suspect they’re pretty close together. I don’t
think you’d want to stay in a room with one that was running for very
long. I keep my small vibratory tumbler (6 pounds of steel shot) in a
closet with a closed door. The noise isn’t a problem.
From a mechanical point of view, the vibratory has fewer things to
go wrong with it. You can also use a 'flow through" system with a
vibratory but not with a rotary. A flow through system allows any
dirt generated by the tumbling process to be flushed out during the
tumbling process.
If it were me, I’d go with the vibratory, there’s less to go wrong
mechanically, they’re faster & easier to use.
Dave
Vibrator tumblers vs.rotary tumblers is a an apples and oranges kind
of thing. Each does its own thing and does it well. The vibratory is
primarily capable of doing a finishing job much quicker, but it does
not shape stones. It is also the ideal medium for micro-peening
jewelry using various media such as ceramic pellets. This method is
especially useful for the jeweler who wants to get a nice finish on
a batch of jewelry in a short period of time.
If you are going to use a tumbler for doing stones it is most
efficient to do the shaping in a rotary tumbler and then switch to a
vibratory for the final three stages.
Making a rotary tumbler is no big deal. The best barrels are made by
Lortone and it is easy enough to adapt them to a home made
rotational device. The critical element is getting the pulley ratios
correct so that you do not rotate too fast or too slow. Information
on tumbler construction is readiily available in the archives of
Rock and Gem or the Lapidary Journal. There are also several
booklets available.
Vibratory tumblers are another matter. In my opinion your best bet
is to buy one from a gun shop. The same tumbler in a catalog selling
to rockhounds or jewelers is usually priced substantially higher.
And, since the cost is only about seventy five dollars, you are
bettter off buying the ready made models.
You might also consider sourcing something used through a rock
club. I just bought a Scott Murray 12 lb. tumbler in new condition
at a garage sale for five dollars…it sells new for over two
hundred dollars !
Ron at Mills Gem Co. Los Osos, CA.
Vibratory tumblers are another matter. In my opinion your best bet is to buy one from a gun shop.
I have looked at gun shop tumblers on the web, and they all say that
they operate only with dry polishing media. Isn’t this a
significant restriction?
Dian Deevey
Hi Dian,
I have looked at gun shop tumblers on the web, and they all say that they operate only with dry polishing media. Isn't this a significant restriction?
I’ve not looked at any gun shop tumblers on the web, but a couple of
friends have purchased tumblers from local gun shops & are using
steel shot in them for jewelry. Could be that what the ads are
refering to is polishing ‘brass’ for reloading.
As part of the polishing process using steel shot the items in the
shot are also hardened a little. This hardening action is not wanted
on brass used for reloading. The brass must be soft enough to allow
insertion of the primer & crimping of the bullet after its’
insertion.
I doubt many gun shops ads consider that their tumblers might be
used for tumbling something other than brass.
Dave
Yes, it can be a restriction…
If you have the money, order from Diamond Pacific. Vibrasonic
tumblers… or someone who can get them cheaper from diamond
pacific… They have a rectangular tub polishers / 12 - 14
pound capacity and you can move up to more capacity with the same
machine, by using larger tubs. up to 50 pounds.
You can use these tubs wet and dry.
1 800 253 2954