I’m trying to research magnetic tumblers. It seems that most are made
either by Ikohe of Japan (a.k.a. Raytech at Rio Grande and other
places) or “Best Built”, apparently a Korean company. I’m looking for
a smaller model. [I do small batches of rings, pendants, and smaller
pieces in fine and sterling silver. I also do some Art Clay silver
pieces that like some “in-the-cracks” polishing.]
The Ikohe’s seem to be very well built and are sold by a number of
dealers.
But they are very expensive. The “Best Built” are not as readily
available, but are less expensive.
Q1. Does anyone have experience with the “Best Built” magnetic
tumblers, especially the small or medium sizes (Otto Frie, Gesswein,
and AJS each carry one or another sizes)? Is there another brand
that works well, holds up, and is not a bank-buster.
Q2. Would I be able to convert a magnetic stirrer unit to a magnetic
tumbler if I simply buy a bowl from one of the venders (like Ikohe)
and add the water and appropriate stainless steel shot? What goes on
under the hood of a magnetic tumbler that is different from a
magnetic stirrer?
What goes on under the hood of a magnetic tumbler that is different
from a magnetic stirrer?
A magnetic stirrer uses a single magnet rotating under the center of
the stirrer’s top plate. It’s oriented with side to side poles, and
the stir rod is also a magnet with end to end poles, so it will want
to stay oriented with the magnet in the stirrer. As the stirrer’s
magnet is rotated around it’s center (think of the arrow on a
compass, made to spin…) the stirring bar follows suit. They are not
necessarily very strong magnets, but since there is a pair of them
interacting, thet get the job done.
The magnetic tumbler on the other hand, spins a disk to which are
mounted, along the periphery, two or more very strong magnets. These
are then capable of dragging along the stainless steel pins in the
bowl above. The magnets need to be much stronger, since the pins
themselves are not magnetized, and there’s a fair mass of metal (the
pins, plus pieces) to be moved along. The magnets used are usually
disks, often 3/4 to an inch in diameter, with the magnetic poles on
the flat faces, so the lines of force radiate UP from the magnet in
a way that causes the pins to also stand on end as the magnet passes
under. At least, that’s how they’re set up on the tumber I have (a
Swest “mini”, which isn’t so small. Don’t know who actually built it.
Works well though…)
I have a small magnetic tumbler that I purchased from Schutz Dental
Group in Conneticut that works really well. As for the bank busting
price, what did you have in mind. Sometimes you also get what you pay
for.
Hey Denny, try making your own. Look up magnetic pin finisher on the
internet there are a couple video’s that show folks who have made
them.
As far as a magnetic stirrer goes I don’t think it would work well.
Seems like the stirrers just spin a small rod on a central axis
while a pin finisher
has a number of magnets in a circle with reversed polarity to
achieve results. I built mine for about $100 works great.
Robert Christopher, at this web site, has posted drawings, parts
list, etc. on how to make a magnetic tumbler. I have
made two using used 1/3 h.p. electric motors, and magnets http://rchristopher.com/MagTumbler/MagneticTumbler.htm
They worked great, and I use them nearly every day. They are not hard
to make, if you are a little handy with tools. I dont believe the
magnetic stirrer will work. If orchid does not permit the web sites
to be post ed google, build magnetic tumbler and Robert Christopher’s
site will be listed. You can also google neodymium magnets for
magnets. A good source for a small tumbler bowl is Harbor Freight,
about $20.00.
You might be interested in this link I found when researching
Magnetic Tumblers–it does a pretty good job of explaining the
technical of the tumblers and has instructions for building your own.
Whether you choose to build your own or buy one, this link has a lot
of interesting and I think valuable
The Ikohe and the Raytech are the same machine, made in Korea just
like the Best Built machine. All magnetic tumblers do the same thing,
just like all cars do the same thing, but you pay more for higher
quality components and additional features. You cannot use a magnetic
stirrer to get the same results, as they would not be powerful enough
to move the magnetic pins with enough force to get results.
Magnetic tumblers have two major benefits-the first being
speed-cycle times are 20 to 45 minutes to achieve bright and shiny
surfaces that would take hours in a rotating or vibratory tumbler.
The second benefit is that the super small pins (.50mm x 5.0mm size
pins is the standard size) ability to reach the smallest recesses of
your work to achieve a bright and shiny surface that requires no
additional hand work.
The least expensive machines will do the same basic thing as the more
expensive machines. As you pay more for the machine, you gain faster
cycle times and more capacity. The smallest machines are for one or
two rings at a time, will take 45 minutes or longer to get results,
and have no speed or forward/reverse control. The larger machines
have greater capacity, quicker cycle times, speed control (often with
forward/reverse) and are meant to be used in production work. The
Ikohe/Raytech 150mm (medium size-around $1000.00) magnetic tumbler is
an excellent choice for production work with quick cycle times, good
capacity (25 ring) forward/reverse and speed control. They have been
on the market for about ten years now and have a very good
reputation. The Best Built machines came out Summer 2009, start at
around $200.00 and so far we have had no problems or returns.
Denny - Before you run out and buy or try to make a magnetic
tumbler, I’ve run across something that might be better. I’m
currently running tests on Diamond Pacific’s Vibra Dry 50,000. It is
dry media with 50,000 diamond and supposedly produces the best shine
in the business. I’ll report in an a couple of weeks.
As to the magnetic tumblers - what goes on inside the tumblers is a
set of permanent magnetics rotating about a center post. They reverse
every so often. The bowls are nothing special - I’ve seen Tupperware
work just fine. What makes the Ikohe ones and others expensive is
that the speed and time to reverse can vary and they have timers for
shut off. The one I have works well and also has dry and wet disc
finishing bowls that work with it as well. They are good in some very
specific situations.
Magnetic tumblers neither tumble or do final shiny finishing. They
burnish with bitty stainless, slightly magnetic pins. The best finish
you can get is kind of a sparkly peen. They work well for ear wires,
pieces with very intricate designs, and for interim polishing on
rings and earrings with heads. They are a disaster for heavy pieces,
pieces with fine silver bezels and mixed metal pieces.
They are a disaster for heavy pieces, pieces with fine silver
bezels and mixed metal pieces.
My experience has been different. I have been using a magnetic
tumbler for cast and fabricated pieces and have been very happy with
the results. Some of my pieces are sheets of dublee, 24kt fused to
sterling with a sterling frame soldered on top, I had trouble
finishing these pieces to my satisfaction and the magnetic tumbler
turned out to be the answer. The gold backround comes out looking a
rich color and very clean. I do a lot of textured sterling pieces and
the magnetic tumbler gives the pieces a very bright shiny polish. The
recessed areas that are a problem finishing were polished in 15
minutes with the magnetic tumbler.
I also have pierced designs soldered onto a textured backing sheet
and I was not happy with any method tried to finish these pieces,
magnetic tumbler did the trick.
I make a lot of elements, cast pieces used in fabrication or just
fabricated pieces for earrings and bracelets. I use traditional
tumbling with vibratory tumblers and after assembly the pin tumbler
does the final finishing. The pin tumbler does something that steel
shot in a rotary tumbler will not do, and I tried many times without
any success.
I do not do large pieces so I do not know anything about how those
pieces are affected.
I will try and post some pictures in the next week.
I second Judy’s statement about heavy pieces and magnetic tumblers.
I do gold jewelry that is non-traditional and heavier than
traditional; they just don’t move in a magnetic tumbler. This is not
a criticism just a statement about limitations.
I want to thank everyone who responded to my post about buying a
magnetic tumbler. And especially those who suggested I build my own.
The several links to plans and specs and the videos are inspiring.
Especial thanks to Robert Christopher. I may just give this a try!
WooHoo!