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This list digest contains the following message subjects:

1. LapDigest News for Issue No. 107 - Tues 1/20/98
2. NEW: Transferring a Cutting-Image from Copy to Slab
3. NEW: A Poor Man's Vibrating Lapidary Drill
4. RE: Drilling - Starting the Hole
5. Re: GFCI
6. NEW: Converting a Metal Bandsaw to a Mudsaw
7. SCHOOLS: SFMS Lapidary Summer Workshops
8. SHOW: National Gemboree show of Australia
9. FS: Lapidary Equipment


Subject: LapDigest News for Issue No. 107 - Tues 1/20/98

I have found many articles from magazines published 20 or 30
years ago, which I would love to reprint here, but have not
done so due to copyright laws. However, I found that if you
completely reexpress what the author said, in your own words,
then you are not violating his copyright. So one of these is
'reexpressed' below, and it adds to our discussion of how to
drill lapidary materials.

Also George Butts describes a way to copy a design onto a
slab; this is very similar to the method used to transfer a
design to copper for etching. It is getting close to surface
decoration, one of my favorite topics, and one we will see
more of in the coming months.

Be good, be careful, and have fun every day, preferably with
someone you love. Do it! Go for it!


Subject: NEW: Transferring a Cutting-Image from Copy to Slab

This is a description of a different way to transfer a design
from a paper copy to a slab, for use as a cutting outline.
The steps are:

..copy the design onto silicone release paper using a copy
machine or laser printer,

..stick a piece of transparent adhesive mailing tape onto
the copy and gently pull it off, transferring the design
from the copy to the tape, and

..stick the adhesive tape, with the design on the sticky
side, onto the slab.

The design visible through the tape is a positive and direct
copy of the original design, and may be used as a pattern
for trim saw cutting..

Here are some key points:

..Silicone resin-coated release paper is heat resistant, to
which nothing adheres except RTV silicone resin (to my
knowledge). A common source of silicone release paper is the
"support sheet" under pressure sensitive laser printer
labels. Just peel away ALL the original paper labels. One
support sheet can be re-used many times by gently wiping off
all residual fused toner after each use. Label support paper
is heavily coated with silicone and, sometimes, the image may
"skid" a bit, distorting the image.

..Slab should be fairly smooth, free of gross irregular saw
cuts, so the sticky tape will mate well. Be sure the slab is
clean (no saw oil) and is thoroughly dry. Lightly burnish
the tape-image really well onto the slab.

..If the design includes a large black area, it is a good
idea to white-out most of the black interior of the original
art work, leaving as much clear area as possible for best
adhesion. A completely black silhouette image would lift ok
but would be non-sticky inside the boundary, peeling free as
the edges are sawed away. If pre-clearing an image center is
not convenient, these are several alternatives: the printed
image can be touched up with a Q-tip coated with almost
anything sticky, you can spray the completely black
silhouette image on the back of the tape with a little
pressure-sensitive adhesive before you apply it to the slab,
you may smear 3M Feathering adhesive directly on the image
(stuck to the tape), and you may put Feathering adhesive
directly on the slab, let that "dry" and overlay this with a
center-blocked image on tape.

..The sticky tape doesn't seem to be too critical but must
endure the usual water-spray while the slab is being
trim-sawed. I worked this process out with common 3M
packaging tape where the saw lube is RV antifreeze (-50
degree Propylene Glycol/water mix) and had no problem. You
don't want a real tough or reinforced type film.

..For images larger than sticky tape width, there are wide,
tacky films like photo overlays but these are expensive.
Consider a pressure sensitive spray on simple cellophane to
make a wide tacky sheet? Haven't tried it; should work.

..The Internet www is a rich source of images which can be
downloaded and manipulated. A flatbed scanner will copy any
original, drawn or from a book, and usually comes with
software for image manipulation, just right for this process.
Direct computer output to a laser printer is handy but does
need a digital image. Fancy copiers with tight turns in the
paper path (after the image is cast) may tend to smear.

..This technique using a laser printer or copier to get a
fused toner image was developed for copper sheet etching.
Here the image on release paper was "ironed" directly onto
the metal. The toner then re-melts and sticks to the copper
when cool to become etchant resistant (ferric chloride, etc).
This is how to make prototype electronic circuit boards by
the onsey-twosey... but that's another story. I suppose, if
the slab were entirely smooth, one could put the release
paper (with image) face down on the slab and, with a padded
weight over that, heat the slab until the toner melted. The
image would be reversed. Haven't tried this; might work.

..Just a note about the obvious use of printer/copier
transparancy film with spray adhesive. This film is quite
springy and difficult to mate to the slab. Being Mylar, it
is also fairly tough so the saw tends to push delicate edges
away rather than saw through the film. You might have better
luck with your trim-saw setup. Remember, the image will be

..Why not simply use the pressure sensitive copier/printer
label itself? The paper is too strong and the adhesive is
poor when it gets wet so the saw "chews" at the image as the
saw gets close to the image. The paper also tends to peel
off and you can't see the slab under paper. Furthermore,
that scheme wouldn't be nearly so elegant or fun!

George Butts <>

...non-commercial republish permission granted...

Subject: NEW: A Poor Man's Vibrating Lapidary Drill

We have been discussing drilling holes in lapidary material,
and yesterday, I came across an article from the November
1977 issue of Lapidary Journal, page 1834-5, entitled:
Kassom. He developed this method; it seems to be a sonic
variation of an ultrasonic drilling method. I have not tried
it so can only report what he says.

He started with a Dremel electric engraving tool; it has a
engraving point at the end of a 1/8" diameter carbide steel
rod. For a drill holder, he used 1/8" brass welding rod
about 1/2" long, and drilled a hole in the end of this brass
rod. A piano wire about 3/4" long serves as his drill. The
hole drilled in the brass rod is large enough just to
accomodate the piano wire drill; the piano wire is then
stuck into the hole and soldered. This assembly is then
inserted into the Dremel in place of the engraving point,
and the setscrew tightened.

He built a stand to hold the Dremel vertically, with the
drill pointing downward. To drill, one hand holds the stone
up to the piano wire drill; the drill is turned on, and the
area is swabbed with a slurry of water and 220 carborundum
grit applied by a small brush or a cotton tipped applicator.
(I think it could also be applied using an eye dropper.) He
puts a pan under the whole setup to hold the slurry and to
catch the drip from the drilling.

He says that most of the holes he has drilled with this
set-up are only about 1/8" deep, and that he can drill more
than 30 holes before the drill wire wears out. This works
out to drilling a little less than 4" on the wire drill.

My Dremel engraver is a Model 280, and operates at 7200
strokes/minute. It also has an adjustment for length of
stroke, with 5 settings from small to large. I assume you
would use a large stroke for this drilling.

He also noted that you could drill non-round holes with this
arrangement. He showed a picture of a test slab which had
both round and square holes in it. To make the special drill
for non-round holes, he used a 1/8" steel blind rivet as the
shank, and soldered a drill blank on the bottom. Then the
drill blank was filed square on the sides.

He used this arrangement to make a channel for a wire inlay.
Using the square drill, he moved the stone slowly under the
drill along a premarked path, keeping the tip supplied with
grit and water. Constantly retracing the path, a channel is
slowly etched into the stone, into which he puts a gold wire.
The channel must be deep enough to hold the gold wire. He
said that he had inlayed gold wire crosses into agate
pendants by this method.
(Note: Concerned about violating their copyrights, I checked
with an authority, who said:"Except for designs, ideas cannot
be copyrighted; only their expression can be copyrighted. So
if you read something and later express the ideas in your own
words, you are not violating copyright of what you read."
Reassured, I wrote the above note from memory without
consulting the original paper. hale)

Subject: RE: Drilling - Starting the Hole

It is a common practice in metal drilling to use a special
punch called a center punch to make a small indention in
which to start drilling. This keeps the drill from walking
around a flat metal surface. To do this, you merely put the
center punch where you want the hole and strike it a sharp
blow with a hammer. The sharp hardened point does the rest.

I had forgotten a similar trick to start holes in lapidary
materials; we have heard many times that in starting a drill
hole on a perfectly flat plane, the drill will tend to skid
and wander. The same trouble for drills started on a slope.
Obviously what is needed is a small indentation in which the
drilling may start. Well, you can make such an indentation
with an electric engraver, such as the Dremel. Just hold the
tool at the point where you want the hole, cut it on and hold
it steady. Very shortly, you will have your small indention.


Subject: Re: GFCI

When I wired my garage for my shop, I used GFCI breakers in
the breaker panel. It was cheaper in the long run, and I was
able to protect 4 circuits at once. There's no worry about
what amperage is in the circuit, either...the breaker
determines it.

God be with you
al macneil
somewhere near seattle

Subject: NEW: Converting a Metal Bandsaw to a Mudsaw

Hi Hale !

Your timing in requesting discussions about lapidary bandsaws
and ring saws is impeccable. I was recently given a large
metal-cutting bandsaw (ca. 7" X 12") and the first use I
thought of was for slabbing rocks. Not gems, just rocks. I
am familiar with the mechanism by which mud saws work (the
Smithsonian's series on Amateur Telescope Making is an
excellent reference & how-to). However, there is no room in
my bandsaw for dipping the blade in the abrasive slurry, even
with an auxiliary wheel. Therefore, I will have to drip the
slurry over the blade just before it enters the cut. I worry
about abrading the guides and backup wheels. I also see a
fundamental tradeoff between the functionality of the brass
(?) band (softer is better) and its life (harder is better).
I presume that a centrifugal pump or "paint stirrer"
mechanism can keep the abrasive in suspension well enough to
transport it to the blade.

Well, now we lean back and awaite the verdict of experience..

George Langford, Sc.D.
(Ed. Note: George, is it possible to buy a diamond blade to
fit your 'new' bandsaw? It so, that is a better solution for
you than to use it as a mud saw! What length is the saw band
on your saw? But let's hear what everyone else thinks..hale)

Subject: SCHOOLS: SFMS Lapidary Summer Workshops

The Southeast Federation of Mineralogical Societies (SFMS)
sponsors 5 one-week workshops in various lapidary skills
including Silversmithing. Three are held at the Wildacres
Retreat near Little Switzerland, NC and two at the William
Holland School of Lapidary Arts in Young Harris, GA (near the
North Carolina border).

These classes are scheduled for the members of SFMS clubs;
however, other interested parties are welcome on a space
available basis. Membership in many of the Federation clubs
is not very expensive and generally open. Cost for the whole
week, including room, board and tuition (but not supplies)
is between $230 and $240 in 1998.

The Wildacres workshops are April 16-22, 1998, August 24-30,
1998 and September 28 - October 4, 1998.
For further information contact Registrars:
Arthur & Doris Mott, 337 Walter Rd., River Ridge, LA
70123-2652, Tele & FAX (504) 737-0259,

The William Holland workshops are June 7-13, 1998 and
October 11-17, 1998. For further information contact
Registrar: Mary Ingram, P.O. Box 440413, Kennesaw, GA 30144,
Tele (770) 427-1108, FAX (770) 423-1374,

Classes are given in:
Bead Design, Cabochons, Casting, Chain Making, Channel
Work, Faceting,I and II, Gem Identification, Intarsia,
Mineral Identification, Opal Cutting, Raku Pottery,
Silversmithing I and II, Wax Design, Wire Craft I and II

Subject: SHOW: National Gemboree show of Australia

The annual National Gemboree show of Australia will be held
at Gawler, just north of Adelaide April 10th. to April 13th.
It will include the seventh International Faceting Competition
where the best five competitors from each nation go into the
final. Details from Rupert Pickrell, 1A Spurgin St.,
Wahroonga, NSW 2076.

Don. & Frances Mason, Bermuda

Non-commercial republish permission granted.

Subject: FS: Lapidary Equipment

I have the following equipment for sale:

Highland Park 6" trim saw/motor: $150
Lortone Beaver w/100 & 220 diamond 6" wheels and 2- 6"
expandable drums and motor: $250
Raytech 6" setup w/ 180 diamond and expandable drum
and motor. $175
Two 8" wheel set ups. One has 100 and 220 diamond and the
other has 2-8" expand drums. $300 for both.

These prices do not include shipping from Greensboro, NC.
Contact me at the address below.
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