I’m hoping you good Orchid folk will share your experience and help
me out with a technical problem I’ve encountered. A friend asked me
to make a pair of decorative sterling scales for the handle of a
folding knife, so I decided on a variation of the traditional Zuni
technique of overlaying a pierced sheet onto a textured back sheet.
I’ve pierced some arabesques and scroll shapes through 18 guage
sterling sheet and am having trouble figuring out how to smooth and
polish the inside walls of the piercings before soldering them onto
their backplates.
My piercing was pretty smooth and even, and I’ve touched up any
rough places with fine cut needle files where I could, but am still
left with lots of narrow spaces I’d like to get more polished. Even
my smallest fine grit diamond dental burs are too thick for some
spaces and they also tend to want to “dig in” and leave a scalloped
surface rather than a smooth, even one.
I have a tumbler with various plastic media, but it’s all too large
to get into these spaces. I also have a magnetic finisher, but know
from experience that it leaves flat sheet pieces with a faintly
frosted finish that’s hard to buff out, and that buffing over
pierced work tends to create rippled “drag marks” even with great
care.
Surely somebody out there has struggled with how to get a decent
finish on the edges of pierced heavy sheet and can help me out.
Sign me…“A frustrated Saw-and-Saw”
Walk In Beauty,
Susannah Ravenswing
Jewels of the Spirit
Germanton, North carolina
I like to use 3M WetorDry Tri-M-lte Polishing Paper (who thought up
that name?) for smoothing really tight spots. Installing a two
inch or so piece of thin sanding or polishing paper in your
jeweler’s saw can help to keep the edges crisp.
I cut thin strips of sanding cloth, put the pierced piece in a vice
and thread a strip through the opening - then rub the strip back and
forth on the inside edges. You can also purchase sanding thread or
thrumming thread - at least I have some I bought several years ago
but I can’t find it in the catalog just now. I like the strips better
because it contours to the shape of cut.
Surely somebody out there has struggled with how to get a
decent finish on the edges of pierced heavy sheet and can help me
out.
Traditionally you use a bunch soft strings. One end is fix to your
bench and the other is pulled to give it tension. The strings are
rubbed with a tripoli bar, and the work is rubbed up and down the
string. You could do the same sort of thing with thin strips of fine
emery cloth, but string is more versatile.
Surely somebody out there has struggled with how to get a decent
finish on the edges of pierced heavy sheet and can help me out.
Sand papers work very well for finishing the inside edges of
piercings. I usually hold the metal in a vise, and cut thin strips
of sand paper, thread a strip though a piercing, and sand. Works
quickly and the finish is wonderful. 3M makes terrific papers
specifically for precious metals, comes in the finest grits (and
micro grits), and they are perfect for this type of application.
Surely somebody out there has struggled with how to get a decent
finish on the edges of pierced heavy sheet and can help me out.
Hi Susannah.
There are a couple of methods I have found helpful.
Use a string or cord with an abrasive charge anchored to the bench
at one end and thread it through the piercing. Hold the loose end
with one hand and the silver in the other. As you slide the metal
sheet along the cord, direct the sheet so that the cord slides along
the edge of the piercing rather than working back and forth in one
area. This will help to keep your contours sharp and avoid those
scalloped effects and you’ll be able to reach the narrower sections
where a file or rotary tool won’t reach.
Something I prefer to the above, especially in a slot or V-shaped
piercing is to cut a narrow strip of medium to fine abrasive sheet
and insert it through the pierced area. Secure your silver sheet in
a safe (plastic or leather-jawed) vice or clamp so both hands are
free. Thread the strip through the piercing and use a sliding action
as described above. You’ll be able to bring the long edge of the
strip right into the “v” of your scrolled piercing where a few
strokes will smooth the sawed edge. Remove and reinsert the strip
with the abrasive facing the opposite direction to do the same on the
opposite cut edge. It is easier to manipulate the abrasive strip if
it is at least 10 cm long. The width can be about 5 mm or so to
smooth long open curves and narrower if the curves are tight.
The 3-M micron-graded sheets are wonderful for this and the wet/dry
variety with the rigid backing (Imperial microfinishing film, I
think) holds up to much use - especially if you need a very narrow
strip. The standard kind with fiber backing (like Pellon - a
non-woven fabric) will easily conform to the contours and wears well
with a lighter touch. I like the 9 micron grade best but if you want
something more aggressive, 15 micron should do.
As an aside, I’ve found the Imperial sheets seem to be more
aggressive in use than the regular sheets in identical grade.
Perhaps this is because the backing is less yielding to pressure than
the fiber?
I am not associated with 3-M except as a very happy customer. Hope
this helps. Happy edge-refining!
You may want to try taking Emery cloth in several different grits.
Cut narrow pieces (1/4 to 1 inch wide) from the strip.
Place the pierced work in a clamp or vise. Place the emery cloth
into the opening of the pierced work and using both hands pull the
cloth back and forth along the edge you are trying to clean up.
If you need to polish the edge before you complete the work, clamp
the piece back into the vise and use a piece of cord or thin leather
charged with a polishing compound such as rouge. Run the cord back
and forth along the edge the same way you used the emery cloth.
Susannah The traditional method of polishing into these crevices is
to use a string and buffing compound, for sterling I would suggest
Tripoli or Zam. While this sounds like it would take forever it
actually goes rather quickly. There are also abrasive cords and
tapes which could be used.
To clean up tiny areas, try cutting narrow strips of sandpaper and
holding them in your saw frame just like a blade. 3M actually makes
special strips for this purpose that have two different grits on a
strong, thin backing, but you can muddle along with ordinary
sandpaper.
You can also apply buffing compound to string, tacking one end to
your bench and holding the other, use like a razor strop. For really tight spots, try putting compound on dental floss.
You can also purchase sanding thread or thrumming thread - at least I
have some I bought several years ago but I can’t find it in the
catalog just now.
You can use string or a shoelace, charge it with tripoli, and thrum
away… tip for repronging more than one prong on the same head,
carefully solder the first prong, the bend the wire in a u shape and
position the wire where you need it to be to do the second prong,
solder it, cut the second but not the first, reposition if you need
to reprong another till all are done, final step, cut the first
prong and finish.
I would agree that the best tool to smooth and polish the inside
edges of pierced work is Wet-'n-Dry sanding papers which are
available in various grit sizes from coarse to ultra fine, and they
are best used wet. But even narrow strips cut from these toughened
papers wear and tear quickly.
So I stick lengths of plastic Electrician’s insulating tape on the
back of the papers, and cut strips with a steel rule and a razor
blade or ‘box cutter’ knife. Cut the combined strips in any suitable
widths for the job. For final polish, I use not thread or string,
but pieces of cotton tape which you can buy in small rolls around
1/4" wide. Rub this with a piece of rouge or tripoli, fasten one
end to the bench, thread it through the piercing, tension the strip
by hand and off you go.
One of the fellows at work tapes strapping tape on the back of sand
paper to provide a strong, reinforced backing. He then cuts narrow
strips of the backed sandpaper (reinforcing fibers of the tape
running the length of the narrow paper strip) and inserts these
strips into his saw frame like he would a sawblade. If you thread
your work pieces as if you were doing piercing, you can sand edges
of holes and cut outs by stroking with your sawframe. This is much
easier than anchoring one end of your sandpaper in a vice, threading
on your work piece, holding the other end and stroking the piece
with your free hand. With a sawframe, you can work at your bench pin
and really see what you’re doing and the saw frame keeps the
orientation of the paper strip how you want it. You can do a better
job keeping surfaces flat and not rounding edges.
Dental suppliers also carry plastic abrasive strips to be used in
this manner. The strapping tape on sandpaper is merely a "homemade"
version.
Traditionally you use a bunch soft strings. One end is fix to your
bench and the other is pulled to give it tension. The strings are
rubbed with a tripoli bar,
This is called thrumming. If you’re not familiar with it, the
newest version of The Complete Metalsmith by Tim McCreight has a
terrific drawing and explaination.
Mea culpa if this is a stupid suggestion. I’m only a beginner. I
haven’t done pierced work on precious metal but has done it on brass
bbokmarks and wood (using dewalt scroll saw). Woodworker’s have
lovely sanding belts that fit into thier electric scroll saws to cut
down on hand labor & carpel tunnel pain. The ones I use have pins,
but I have seen them at woodworker shows without. Couldn’t you use
these in your hand jewelry saws before dapping? I know I use the
jeweler’s saw blades in the scroll saw. I used to use the abrasive
thread by hand, but got to tell you, it was tough on the fingers when
I twirled it around the fingers. I realize on the much finer fretwork
you’ll still have to use the abrasive thread.