Edited and Published by Hale Sweeny
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Associate Editors: Geo. Butts, JR Shroeder, Steve Henegar,
Margaret Malm, Sam Todaro, and Ed Elam

This list digest contains the following message subjects:

1. LapDigest News for Issue No. 296 - Sun 5/13/2001
2. NEW: Tumbler Noise
3. RE: How Do You Cut an Egg Shape? (revisited)
4. NEW: Trip Report from Aussie Opal Country
5. RE: Tile and Glass Drills
6. RE: What Acid Will Clean Crystals?
7. RE: What Acid Will Clean Crystals?
8. RE: Sphere Preform Cutting Jig
9. RE: Tumbling Cast Metal Parts
10. RE: My Saw Doesn't Cut (a reprint)
11. FS: Adams Sphere Machines


Subject: LapDigest News for Issue No. 296 - Sun 5/13/2001

As I told you, I was going to Wildacres for a week and then
on to a beach for a week. Well, I never got to either of
those places, but have been mostly in bed with a bad chest
infection. Just now starting to feel better...

We will soon publish the 300th issue of the Digest, which is
somewhat of a landmark, and I am planning to include a short
'history' of how the Digest got started, and include a list
of the first members.

This has been Mother's Day. I hope all of you took the
opportunity to use this day to tell all of those close to
you how much you care for them and how much you appreciate
your time together. If you didn't, why not do it now? Time
is always short, and there is no better time than now.


Subject: NEW: Tumbler Noise

I have just come back to stone tumbling and polishing after
a thirty years absence. I have a two pound tumbler that is
extremely noisy. Has anyone else had this problem? I think
the only solution would be to build a box packed out with
soundproofing material. I will be most grateful if anyone
out there has any other suggestions. Houses in England are
very close to each other so I have neighbours to think of.

Can anyone out there assist me?

All the best.

Alan Monk
Alan: First, I had the same problem, and put a big piece of
plastic foam (as used in packing electronic gear/ computers)
under the tumbler. My tumbler was on a table, and this cut
the noise sent through the table top to a considerable and
acceptable degree. If this doesn't help enough, then cutting
the noise sent through the air - as you suggest - by sound
proofing would be my next approach.

I hope other members will have suggestions, as we all must
have been bothered the same way. Alan, let us know how it
comes out, and what you do to cut the noise. hale

Subject: RE: How Do You Cut an Egg Shape? (revisited)


I did finish up the plans for a jig to rough grind pre-forms
for eggs.

It is a hand operated device that rotates a dopped stone
against grinding wheels. The shape of the egg is developed
with a cam below the stone, sort of like a tracer attachment
on a lathe. Depending on how far the jig is positioned from
the grinding wheel determines the scale of the egg in
relationship to the cam. For my cam, I took some eggs from
the fridge an picked one out with a pleasing shape. The jig
is fairly simple and can be built with simple tools, i.e.,
drill press, table saw, and hand tools. There is a
dimensioned drawing of the cam.

My plans are just for the jig! The builder will need their
own 6" or 8" grinder/polisher setup.

Sorry, I haven't gotten around to putting up the plans on a
web page yet, if someone is really interested we could work
something out. A nominal fee for snail mail, or trade for
some rocks or something?

Jeff in Kalamazoo

Subject: NEW: Trip Report from Aussie Opal Country


As I write, I am washing off my opal rough and getting ready
for the 8 hour car ride to Lightening Ridge, which we'll
make tomorrow. The last week has been an incredible
combination of wonderful weather, great tucker (food) and
back-breaking fossicking. We've just been trucking over
heaps of backstow (the overflow taken from the opal mines),
picking out opal nuts and other bits that might contain
color. Back at the camp, we get our bucket of water and
pick, and crack them open. I have far more appreciation for
the time, work and skill entailed in getting the opal from
the ground to the cutter. And there are some fabulous
cutters here in Yowah, with a lot of tips which I'll make
notes on and share when we get back. It's all very informal,
very primitive. The only convenience is plenty of hot water,
as Yowah sits on an 80 year old artesian hot water bore
which brings the water to the surface at 120°F. Unlimited
hot water for showers and washing. The problem is getting
it cold enough! And ice is at a definite premium.

I'll try to write again from Lightening Ridge. I'm not going
to send pictures now, because the computer I'm using is very
slow and the pictures would take forever to download.

Talk to you again from Down Under.

Jackie Paciello

Subject: RE: Tile and Glass Drills

Typical department store glass bits will drill some thin
rocks, and most glass and tile. They are rather slow and
require constant lubrication to cut effectively and maintain
cutting ability. Too much downward pressure and your bit
will dull and the material will shatter. It takes time to
learn to use them properly on various materials. I make a
crater around the work area with caulking, silicone (gel
toothpaste will work for quick/light jobs). Fill the crater
with a suitable lubricating fluid, some people use kerosene,
but I generally use a light household oil or air tool oil.
These bits will work, though diamond drills and burrs are
definitely better suited to typical lapidary tasks.

Ron Winter, Auburn, Washington.
In search of: The Mother of All Geodes!

Subject: RE: What Acid Will Clean Crystals?

Hale -

This one more comment may be of interest. When heating and
cooling oxalic acid solutions with quartz crystals, one must
be very careful to change temperature slowly, particularly
during cooling, or the crystals may fracture! I have found
with large specimens of quartz that were severely stained
that placing the crystals in a plastic bucket of oxalic acid
solution and just placing the bucket out in the summer sun
for several weeks, adding water as needed, does a fine job
of cleaning up the crystals.

Harry Billica

Subject: RE: What Acid Will Clean Crystals?

Our Trip director read the post on cleaning crystal and
told me that it was what he did but would have put in bold
not sure that muriatic acid would be that violent but I am
not going to experiment. In any case every time I have
read about acid I have encountered that warning. If it
keeps one person from losing something vital it is worth


fun and time saving for the rockhound and lapidary

Subject: RE: Sphere Preform Cutting Jig

I went to the local welding shop and had them weld a 1-1/2
inch angle iron on a 3x6 inch steel plate. I use a C-clamp
to attach the jig to the saw feed. Once you have cut the
cube, you use the jig to cut the other 18 cuts from the

There was an article in Lapidary Journal about 35 years ago
that gave a formula for how much to remove from the cube
with each cut. I could locate the formula if anyone is
interested. But I eye-ball the cube and take off about
1/4 of the face each cut.

Keith Smith
15 Winchester Road
Farmington, MO 63640
(573) 756-2284

Subject: RE: Tumbling Cast Metal Parts

Have you tried "Tumble Finishing For Handmade Jewelry-Mass
Finishing on a Small Scale", second edition by Judy Hoch,
softbound, 32 pages. Available from Rio Grande
(800-545-6566) for USD $11.95.

Even though it's only 32 pages long, this book is right on
target with what you are talking about. The author's goal
is to show small manufacturer's how to go from casting to
tumbler to display case, with no manual operations. I've
bought the book and have read it and assembled all the
required components, but have not had time to test her

The book is easy to read and is very practical. It was
clearly written by someone who has done the things that she
talks about.

As far as tumblers go, I use, and recommend, the
mini-sonics. I've tried vibrating tumblers and IMHO, the
mini-sonics are hands down winners. They are a little more
expensive, but they are much quieter, a little bit faster,
and do a better job on a wider variety of materials. Since
they have no real mechanical parts (they use a magnetic
switch that goes on and off very fast) they should outlast
vibratory tumblers as well.

Best of luck,


Subject: RE: My Saw Doesn't Cut (a reprint)

Dear Hale:

You recently reprinted an earlier paper by Bill Ritter on
recommendations for cutting oils. His recommendations are
very valid, but Contempo Lapidary is no longer in business;
we purchased them in September 1997. Contempo's brand
"Finecut " oil is not now sold, but we do sell a very good
cutting oil called "Roc-Oil". Roc-Oil is much nicer to work
with than the standard oils or fuels. It is non-hazardous,
non-toxic, and non-flammable under normal conditions. It
has no odor, won't burn your skin (unless you're very
sensitive) and has a flash point of 275 degrees. It cuts
great in any rock saw. You may order Roc-Oil or request
a catalog by calling us toll free at 800-253-2954. We also
sell sharpening sticks.

Diamond Pacific
Customer Services

Subject: FS: Adams Sphere Machines

We manufacture four sizes of sphere machines.

.. A marble maker/refinisher at $300.00.
.. One that will make up to a 3 inch sphere at $400..00,
.. One that will make up to a 5 inch sphere at $500.00, &
.. One that will make up to a 7 inch sphere at $600.00.

Plus shipping.. Please contact me at 303-936 6600 or
write to the address below for more information.

Joe adams
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