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For polishing it is recommended to use primarily bristle brushes for
most of the removal work and to follow up with a buff where necessary.
Feel free to use a lot of compound, it is the compound that does the work,
not the buff. Old polishers would have dozens of shaped and turned wooden,
leather and even paper shapes and wheels to go on the spindle for different
problems.
A paper clip serves very well as a handle for any small part with a
hole in it; one threads the paperclip through and then holds it while
polishing the small part.
A general rule for dealing with institutions is to make friends as soon
as possible with the janitors and security guards as they will have a
great deal of control and impact on your life. Among other things one
can ask cleaning staff to collect the circular centers of the large "scotch
brite"®-like discs that are used in big floor polishing machines. The
circular centers are about 4" or 10 cm across and are normally thrown
away. If one hardens their centers up with hot glue or epoxy then one
has almost free abrasive wheels for satin finishing. They can of course
also be used as pads for cleaning metal surfaces for soldering and solder
before use.
A very useful tool is a cardboard disc sander. One uses the side or
large flap of a fairly rigid corrugated cardboard box. Make sure it has
not been bent or creased to damage its rigidity. Make sure one side is
smooth. The disc will be placed onto the tapered mandrel of a polishing
machine. One begins by measuring the distance from the middle of the tapered
mandrel to the closest part of the polishing machine or its hood with
dividers. The dividers are closed slightly so that the disc clears all
parts of the polishing machine and hood when rotating. Remember that a
cardboard disc will tend to ride up the mandrel so give sufficient room
for this. One then scribes the appropriate sized circle onto the cardboard
making sure that the center hole actually penetrates the cardboard. The
disc is now cut out carefully with an X-acto® knife. Remember that most
injuries in art schools are from X-acto® knives and do this carefully.
Then one takes a piece of 220 grit emery paper, spreads rubber cement
(not white glue-it dries in lumps and ruins the tool) onto the slightly
corrugated side of the disc, places it on the back side of the emery paper
and turns it with some pressure from the heel of your hand so as to evenly
spread the rubber cement on all surfaces to be joined. The disc is lifted
off and fanned over the emery paper so that both surfaces become tacky,
dull and mat. The two surfaces are then pressed firmly together and smoothed
to effect a good join. One then trims the emery paper flush to the cardboard
disc using a knife or scissors. Keep it close to the cardboard. 3M® has
a 100 grit aluminum oxide paper that outlasts anything else. I have seen
one sheet last through a whole workshop of hammers and chasing tool refinishing.
Wearing safety glasses the disc is now placed onto the mandrel while
it is spinning so that it rides up to the third or halfway level on the
taper, piercing through the emery paper. Get your hand off and away from
the rotating disc quickly as any emery paper sticking out past the cardboard
can inflict what might feel like the worlds worst paper cut. One holds
the back end of a steel file or another piece of steel onto the edge of
disc and paper to trim off any overlap and make the edge safer. The motor
is now turned off and the disc removed.
The area around the center hole is now strengthened by melting a hard
file-a-wax or other wax around the center. If one quickly places a torch
onto it and removes it the wax may melt and run into the cardboard about
the center making the hole last longer in use. If using wax make sure
it is dry and set before use as otherwise a vertical spray of wax occurs
when the disc is turned on. Better than wax is 5 minute epoxy which can
make a very permanent strengthening support. If using epoxy let harden
before replacing on the mandrel. With epoxy one can also place a little
mesh circle around the center to provide a little more rigidity. When
in use there are a number of cutting speeds available depending upon how
close one is to the spindle; further out is faster: closer in is slower.
Within a very few minutes there are also a number of grits available as
the more used parts of the disc become finer so that one has a lot of
choices in speed and grit size all on the same tool and accessible with
a minimum of hand movement. To stiffen the disc while it is running one
can hold a piece of wood behind it on the paper side while it rotates
so as to obtain a more rigid surface for faster flatter cutting.
The tool is used to sand flat surfaces onto jewellery replacing much
more expensive jewellers laps. It is unsurpassed for reshaping commercial
and handmade chasing tools and hammers. One can go directly from this
sanded surface to a polishing buff. On steel one uses Fabulustre® on a
buff and the process of completely refinishing a hammer can be reduced
to five minutes or less.
It is absolutely essential that the air and dust intake on the polishing
machine be completely blocked off with a piece of cardboard when using
this disc as sparks can be produced which will set the cotton lint and
dust in the filters on fire. This is a very real danger of fire with such
flying sparks-I've seen it happen twice.
If one places a polishing compound such as tripoli or Fabulustre® onto
the smooth paper side of the disc then one has an extremely fine polishing
lap that can produce superb flat surfaces on jewellery with plane surfaces.
If one makes a traditional type disc one can rubber cement a piece of
linen writing paper onto the paper side for an even smoother polishing
effect. It is far superior in flat finishing to expensive hard felt buffs
that jewellers use. Plain paper would probably work well for polishing.
Several discs with different starting grits are useful. For a minimum
cost and preparation time this type of disc sander and polishing lap offers
a great deal.
Some polishers will take a stiff paste of baking soda and water or icing
sugar and water and fill up holes for stonesettings and other places they
don't want polishing residues in on a piece of jewellery. When it dries
this prevents accumulations of polishing compounds in those places. When
the polishing is finished one washes out the water soluble paste and so
saves time and effort in cleaning out such places.
When holding a ring onto a felt ring polishing mandrel on the machine
it is often useful to have a short piece of a leather belt looped over
so as to hold the ring in place on the mandrel while it is polished. The
two ends in the hand become a handle. This also protects the fingers from
heat while polishing.
A tool can be made from a wooden clothes pin which is hollowed out slightly
with a large round burr in the curving hollows already in the jaws. This
holds a ring while polishing primarily for the flex shaft but will also
work on the large inside ring buff on the polishing machine.
Another version of the same type of tool for holding a ring while polishing
is made by taking a lath or similar rectangular cross sectioned piece
of wood and cutting a circular hole near the end. The inside of the circle
is carved away somewhat with a round burr in a similar manner to the clothespin
in the previous description. Then the lath is slit down about two thirds
or three quarters of it's length with a wide sawblade (band saw) and if
possible the end of the slit is drilled so as to help prevent the wood
splitting in use. To use it the wood is flexed open slightly, the ring
inserted into its rounded groove and the tension of the lath holds the
ring tightly for polishing. Some people like this one because when using
the flex shaft they can rest one end on their shoulder while they use
it.
There are also metal clamping and holding tools designed to hold rings
while polishing available from commercial suppliers. These work very well.
Holding items for polishing is an art form to itself. In factories they
sometimes cut a hole in a piece of steel sheet which surrounds and supports
the part to be polished. The steel sheet with the hole in it is then carefully
attached to a wooden dowel of appropriate diameter with countersunk screws.
This is then used to hold the production component in place while it is
held against the buff. For a single cast production item I have sometimes
heated up the piece and working quickly, burnt a hole which fits it into
a piece of wood to hold the piece in place while polishing.
Never use gloves while using a polishing machine! I have seen and heard
of some pretty nasty accidents from this. You never want to get your hand
tangled into an powerful electric motor. Always work with respect for
power tools, don't talk while using them and keep your attention on what
you are doing. In a serious accident one's first thought is often "that
was stupid".
Some people use "alligator skin®" or similar webbing tape combinations
to protect their fingers while polishing. Even masking tape has been used.
Usually though one uses cut off leather fingers from gloves and uses them.
A German polishers trick is designed to avoid the possibility of being
trapped in the buff and still use a cloth pad to keep heat effects down
and keep one's hand cleaner. If one places a strip of sheet about 3 inches
wide and 8 inches long when folded tucked under the middle finger and
over the ones on each side of it then one can hold items which get hot
from polishing without burning one's fingers. One uses a leather thumb
as well. If the cloth is caught then it is whipped from the fingers onto
the wheel without any chance of damaging the hand. Make sure you have
it right and try snatching the cloth from your hand suddenly a few times
so you understand how it works before you try it with a polishing machine.
This is potentially dangerous!
There is an attachment for a standard polishing machine spindle available
from companies such as Gesswein which hold a 2mm burr shank, which is
the standard size flex shaft tool shank. It is brass in color and resembles
a collet chuck. To change tools one has the machine running and gently
presses ones fingers onto the rotating chuck. This somehow allows the
flex shaft buff or bristle brush or whatever to easily come out and be
replaced. When one releases the slight pressure of the fingers the tool
is fixed in place. Because the tool is running at all times this is very
efficient and easy to use. Some shops have a special motor set up just
for this tool for small jobs.
Burnishers
There was a time before polishing machines (and still in many places in
the world where there is no electricity) when most polishing on metal
was done with burnishers of various types. Burnished finishes are durable,
bright and hard. Good burnishers may be filed out of high-carbon steel
drill rod, hardened and tempered and hafted. The process is that a harder,
polished material is rubbed with or without a lubricant (it is better
with) against a softer material (the metal) giving it a similar degree
of polish to that of the burnisher. Burnishers are often used today to
highlight edges in jewellery, to give a piece a 'frame' composed of very
thin light streaks off the edge itself. They refine and define details
in stonesetting such as the outside edge of a bezel or the fine work of
a prong setting. They accentuate the edges of all parts of a setting or
a piece of jewellery.
Agates, hematite, jade and so on make good burnishers but take a while
to make. A nice stone burnisher is really nice to have. One can buy an
interesting tumbled rock shape cheaply, take the bristles out of a metal
ferruled paint brush and set and glue the stone in place in the ferrule
to make an excellent stone burnisher equivalent or better than $20 ones
from Germany. The ones in the diagram have been combined with a oil or
acrylic paint brush so they function as a bench brush and burnisher combination.
Needle files may be converted to small burnishers quite easily by carefully
grinding, sanding and polishing them without overheating them which would
ruin their temper. I prefer a polishing compound called Fabulustre® for
polishing steel. Used carefully it can even do some of the work normally
done with fine emery on the steel prior to polishing.
Chasing tools may all be used as burnishers. Every chasing tool you
make is another burnisher for your collection.
Hammers are burnishers with long handles.
Burnishers are often kept bright by having a piece of board with a thick
piece of leather glued to it. One rubs the burnisher up and down the leather
until a groove is formed. By placing ruby or diamond powder and a little
oil in it one can keep the burnisher very shiny. Rouge and Fabulustre®
also work.
An old bur can be broken off. The end heated is and then bent over.
Harden and temper it to a blue on the body and light yellow at the tip.
It is then smoothed and polished and when used in a flexible shaft it
works like a rotary burnisher; like a hammer and fills in pits in castings,
gaps and so on.
A commercial rotary burnisher may be purchased from Fischer in Germany.
It is extremely efficient for filling pits before resanding and polishing.
It consists of a number of roller bearings around a drum. Each functions
like a little rounded hammer to smooth and blend the metal surface. The
Fischer Company order number for a general purpose size is 'Nietrad' Number
3653/080.
Joe Dule in New York uses a steel clock gear on it's spindle as a rotary
burnisher. I use steel as well as brass gears as wax burs when carving
filing waxes for casting models. It is also useful for riveting. Other
versions include a nut soldered to a small bolt and old barrel burrs with
5 or 6 flat ground sides.

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