Dear Tool Timers,
This week I want to talk about jewelry polishing. The first thing I
want to address is how to spell the work polishing. I spell it MONEY.
Polishing is truly an area that will pay for itself over a period of
time. I probably could talk for a couple of hours about stories
centering around the polishing of jewelry. I’m not just talking about
shiny things here folks. Proper polishing will also get you a better
price for your jewelry.
In the manufacturing workshop I apprenticed in the owner once told me
that the material (gold) he polished off the castings (after
refining), paid all the polishers salaries for the year. He had eight
polishers working full time for him. He was very careful about where
all the sweeps and dust collection material went. Another shop in
downtown Minneapolis moved from one building to another. After they
moved out they went back tore out the carpet in the old location and
made $15,000.00 from refining the carpet. I spell polishing MONEY.
I will do two or three Tool Times on polishing. I’m sure all you
critics out there will have various opinions about what I recommend
but I value all comments. This is what I learned as an
apprentice, what I use in my own shop and what is taught in my
polishing class. This first thing I want to clarify is that I am
talking about jewelry store type jewelry. Within this jewelry store
definition are three areas of focus. The first is polishing in
manufacturing. The second is repair polishing. The third is polishing
one of a kind special order items. I will also compare a small shop
set up to large shop facilities. I’m sure many comments will fit in
any of these areas.
Within the manufacturing focus of polishing you need several
different specific polishing supplies. These supplies apply to flat
surfaces, curved surfaces and the blending the two areas together. The
preparation before polishing will also be of interest because in large
scale production very little is done at the jewelers bench. On fine
jewelry I also do not tumble finish much of the product. Not unless I
cannot reach by any other means the area I need polished. Tumbling
will round off the sharpness I want to maintain. I don’t want my
pieces just shiny, I want them polished to give me the best looking
product (which goes with profit).
With regards to manufacturing jewelry I will talk about the supplies
relating to the cast piece of jewelry. I don’t do stamping. The CAD
CAM stuff I do is also all cast. So you get the casting info. Rings
will be the example. I will talk later about polishing motors and dust
collectors.
Let’s assume from wax to cast product everything turns out OK. After
cutting the object off the tree or spru button (as close to the object
as you can), you weight it. This fits in the pricing structure. If it
is a ring it may be lightly tapped round on the ring mandrel now. I
use a rawhide mallet. This actually helps start the polishing process
by compressing the inner material of the ring. Some folks hallmark /
trademark now some later. Again all done in the polishing room.
Here comes the tool time stuff. I don’t file the spru off I grind it
off. Let’s say I have 50 rings to do. I want my time spent wisely.
Remember you are paying yourself or someone else $15.00 to $20.00 per
hour to do this. I can’t be running back and forth from one area to
another doing one ring at a time. This grinding wheel I use is a GMX
120 or 180 grit aluminum oxide wheel. I use the 6" x 1/2" size.
Gesswein and Rio as well as others carry them. I also have older ones
in various sizes. It can go either on a special Bolt on spindle for
the polishing motor or screw directly on the tapered spindle. These
are shaped with a truing stone to what ever shape I need, flat, curved
or sharp edged. This will leave an emery stick surface on the object.
This replaces the file and emery stick at the bench. This is emery
paper rotating at 3500 rpm so be careful. As they get older and
smaller I shape them for different purposes. Flat surfaces work the
best with these wheels but you can round off areas also. Some rounded
areas are just left alone and wait for tripoli brushing (next week).
You do as much of the surface as you can reach. This is a LIGHT touch.
You can take and thin a piece down in the blink of an eye.
The ring inside is next and I use a rolled up piece of #320 3M wet or
dry emery paper. #220 will also work but my first choice is the #320.
Not emery cloth but emery paper. The sheet of emery is divided and cut
into thirds the long way. The sections are now rolled into a tight
tube. This is about 3 inches long. Usually two of these rolled sheets
will fit inside a ring nicely. If you buy them they are called emery
rolls and sold a lot shorter in length. A lot more expensive also. On
the one end I place a rubber band stretched and rapped several times
around. The rubber band end goes on the tapered spindle first. The
motor spindle rotates down so you need to put the rubber band on the
left side of the roll. If you put the rubber band on the wrong end
your roll will ruin itself when you try to use it. When one layer is
used up I can easily peel off another and have a fresh surface. Put
this spent piece in the recycling bin. When necessary add another tore
off sheet from your original piece. You can purchase the paper at most
hardware store for about $.50 to $.75 per sheet. When placing this
emery roll on the spindle for the first time if you have a steamer,
steam the hole at that end. It will soften it for putting on the
spindle. The spindle will score the steamed roll and help it spin true
and centered. This will again be like an emery stick surface. Ready
for tripoli polishing.
The only thing left are the ring sides. This is done last with a
thinner GMX wheel. This wheel is also sharpened to reach tight areas.
Keeping your jewelry edges sharp will give you more of the jewelry
store product. Even junk pieces get more money spent on them if they
are polished well. In a larger shop most of the GMX work is done on a
split lap polishing motor. this will be addressed when I talk about
motors.
Now here is an interesting thing to do. If you have weighed the piece
before, weight it again. You have now reclaimed a small amount of
material. Multiply that by 50. You can see why my old boss loved the
polishing of jewelry. Also remember you have priced out your piece as
a rough casting. The difference you pocket! This is how the
manufacturers do it. I don’t write the rules I just try to learn them.
Isn’t this a great idea! Charge the customer for material you keep. Do
it with gold and smile all the way to the bank. Again I’m talking
about production jewelry runs.
The pieces are now ready for the next step. Tripoli polishing will be
next week.
It’s 12:30 am here so good night all.
Best Regards till next time Tr the Teacher Todd Hawkinson