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This list digest contains the following message subjects:

1. LapDigest News for Issue No. 185 - Fri 12/11/98
2. RE: Any Comments on "All-You-Need" Flat Lap?
3. Re: Need Information on Cabmate
4. RE: Need Information on Cabmate
5. Re: Need Information on Cabmate
6. Re: Polishing Pads [Speed]
7. Re: Polishing Pads [Speed]
8. Re: Polishing Jade
9. Re: Polishing Jade
10. BIO: Robin Pascal


Subject: LapDigest News for Issue No. 185 - Fri 12/11/98

I recommend that all of you take a look at the website:
which shows gems and minerals in the Smithsonian collection.
Well worth the time!

Just noticed that the membership is over 1400! WOW!

Now that we have a website, we can do things we never could
before. On the website, we can show plans, for example, of
how-to-build lapidary equipment. And this is something I'd
like the Digest to do - on the website. I have started by
asking a member to send us plans of how he built his own 6"
OR KNOW WHERE WE CAN GET SUCH PLANS (in the public domain,
of course), PLEASE LET ME KNOW.

It's getting on toward Christmas. May each of you have a
wonderful and peaceful holiday season.

.. and have fun!!!


Subject: RE: Any Comments on "All-You-Need" Flat Lap?

I looooove my Hi Tech All-You-Need flat lap!!! I bought
mine at an Inter Gem show almost six years ago. Although
I'm primarily a jeweler, I cut/polish a lot of my own
stones and have used it mainly for freeforms.

In the six years I have replaced my 100 and 180 grit
wheels once because I was pressing too hard at first and
wore them down, but all the other wheels are still fine. I
also use their small leather wheel with diamond slurry for
the final polish on many stones. It is light enough that I
have carried it around to an introductory class I used to
teach and two of the students bought one immediately. As
far as cleaning the tray - I take it into the garden -right
outside my studio-and hit it with a strong spray from the
hose. My studio is packed with tools and 'stuff' and the
small amount of space it requires, both for storage and use,
is a big asset!

Try it - you'll like it Mikee!

Nancy Bernardine Widmer

Subject: Re: Need Information on Cabmate

To Bob Lombardi:

My understanding of Crystalite (& other's) diamond meshing
system is as follows:

Mesh refers to the number of holes on a screen per square
inch. Thus your assumption of 325 diamond paste being
coarser than the 600 diamond impregnated lap is correct.
But, the difference lies in the medium to which it is
applied. The 600 diamond is sintered (pressed partially
into) then plated over onto a hard surface, whereas the 325
diamond paste has been rubbed into the cloth surface of the
FlexPad. The size of the particle being left exposed is
smaller than the sintered diamond, and thus produces
scratches of a smaller depth.

Remember, polishing is basically producing smaller and
smaller scratches closer together.

Mark Greenbaum
M.G. Designs
- The best in Custom Handmade Jewelry and Gemstones -

Subject: RE: Need Information on Cabmate

Hello Bob,

How can bigger grit sizes make a lesser cut? Seems odd but
not when you consider the medium for carrying the diamond.

I have many laps and devices for faceting, carving, cabbing,
inlay etc., and different materials allow penetration of the
cutting diamond to different degrees. For instance when a
diamond is sintered or plated to steel almost the entire
diamond is exposed as a cutting tooth, whereas on a soft
canvas and resin cloth almost the entire diamond is embedded
leaving a very small cutting tooth. Other media such as
copper, bronze, plastics, wax, and wood will all hold
diamonds differently and the resulting finish will therefore
vary. For instance 8,000 diamond and Vaseline on a grooved
(semicircular channel) Corian lap will produce a mirror
finish on star sapphire or jade.

Hope this helps.

Anthony L. Lloyd-Rees. ICQ# 15173706
web site: http://www.opalsinthebag.com

Subject: Re: Need Information on Cabmate

The CabMate is setup with a 180 grit wheel, 600 grit thin
disc, and then sanding and polishing with the 325, 1200,
and 50K diamond compound. The 600 grit disc is a metal
bonded diamond plate that tends to be more aggressive than
a comparable 600 grit diamond compound and Crystalpad. In
other words, diamond compounds will cut smoother than a
metal bonded disc.

As far as other backing discs, a Crystalite flexodisc will
work fine, along with any 6 inch disc with a 1/4-20
mounting bolt or 1/2" arbor. The CabMate is very flexible
to use and will accept a wide variety of accessories.

Peter Erdo
Graves Company

Subject: Re: Polishing Pads [Speed]

My equipment is powered by floor polisher motors. These can
be obtained at many garage sales very cheaply, a buck or
two at most. A simple check to make sure it has brushes and
you will have a powerful motor that can be wired to a
speed control (rheostat) and a reverse switch. I have had
no problems with these motors under commercial applications
over the last 24 years.

I agree with other posters that speed control is essential
for achieving a consistently rapid polish on all gems.
Without commercial considerations a constant speed polishing
head can certainly produce show quality results however if
your earnings are directly related to your polishing times
it is of limited use.

Anthony L. Lloyd-Rees. ICQ# 15173706
web site: http://www.opalsinthebag.com

Subject: Re: Polishing Pads [Speed]

<< I don't know how many Genies Diamond Pacific has sold
but they all spin at about 1725rpm and somebody has probably
polished every stone there is on one. Conversely, somebody
probably has had trouble with every stone also.>>

The RPM is constant, however the surface speed varies a
bunch. Assuming that you are using the disk on the end of
the shaft, and not the 14K "polish wheel". Work the center
of the pad for the stones that require a softer touch such
as opal, and if you need the heavy duty polish for something
like jadeite, use the outer portion of the disk. It is not
the best answer to your polish problems but all in all, a
very good compromise.

Don at Campbell Gemstones.

Subject: Re: Polishing Jade

Gil Shea said:

<< but please when cutting stone of any kind, don't work it
wet unless...>>

I work a lot of Jade ( Nephrite), Malachite, Black coral
etc. and only work them wet , I trust this was (when he
said: "don't work it wet) a typo which needs to be corrected
before someone actually starts dry sanding some of the more
lethal stones.

Tony Lowe (KIWI)
<tonylowe@pop.ihug.co.nz> .:.
Auckland, New Zealand ......... ::o::
```;;;;;;''' `\
(Hale's Note: I agree, Tony, it MUST be a typo. I think he
meant to say 'don't work it dry'. And by the way, that
is a great kiwi! hale)

Subject: Re: Polishing Jade

In regards to what Gil wrote about dry sanding jade
(nephrite, actinolite) he is indeed correct. The BC jade
someone asked about at the beginning of this thread comes
mostly from old asbestos mines. Hopefully we all know by now
that asbestos causes lung cancer and special care should be
taken to NOT breathe the dust of these stones while cutting
or polishing. This is easily done by using water. Polishing
compounds are usually wet or pasty anyway and won't create
any dust so there shouldn't be any worry there.

And since this is a moderated NG, you won't see any flames
here. This is one of the nicest groups I belong too. Very
refreshing...thank you Hale.


Subject: BIO: Robin Pascal

My name is Robin Pascal and I live and work in Houston,
Texas. I have been cutting stones since 1994 when I took
a lapidary course at the University of Houston while
preparing for my BFA in jewelry/metalsmithing which I
received in May of 1996. I am a full time metals and
lapidary artist working out of my home. I cut stones for
my own use in my jewelry and sell stones to jewelry stores
and other jewelers. I cut mostly free form stones
(because I hate to grind away rough). I belong to the
Houston Gem & Mineral Society, Houston Metal Arts Guild,
and Art League of Houston.

My husband and I are avid rockhounds. We usually take
two collecting trips each year, searching the guide
books for sites as well as stopping at any rock shops
that we see. I am particularly fond of drusy, and
collect and/or buy all I can. My husband and I have been
helping a neighbor with his 45-year old rock collection,
and consequently have access to some incredible rough and
mineral specimens. We sold rough and slabs at the recent
Houston Gem & Mineral Show, and I now have a lifetime of
exquisite and rare cutting rough from this collection.

My equipment consists of an old Rock lapidary unit,
of which I only use an 80 grit Crystallite diamond wheel
for forming. My main lapidary unit is a High Tech
Diamond 6" "all-in-one."

Robin Pascal
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