Drilling semi precious materials

Everything I read or hear about the drilling of semi-precious
materials–agate, lapis, amazonited etc.–indicates that drilling is
a slow and tricky procedure. BUT–every time I go to a gem show I
see, literally, tons of strings of stone beads, all drilled, selling
for a few dollars each. My question: How are these beads getting
drilled, by what method–and where–and by whom?

Andy

The drilling of that kind of material is tricky but it can be done. I
have done some using alot of water and going slow. as long as you
have enough water and go slowly it can be done. I strongly suggest
you get either diamond plated bits or burrs. use alot of water and a
slow speed dremel or drill. I have worked with turquoise, opal, and
Garnets. this way works best for doing single holes but for going
through the entire stone you should have a thin bit and go slow.

Brian

How are these beads getting drilled, by what method--and where--and
by whom? 

I’m guessing ultrasonic drills. They work with a vibrating fixed bit
with a water and aggregate feed. They are pricey. $28,000-$37,000
was the quote I got from Sonic-Mill a couple of weeks ago. There’s a
gentleman on this list that specializes in custom briolettes so he
may chime in with some real expertise.

I have some turquoise nuggets that I need to drill. Drilling
turquoise shouldn’t require an ultrasonic drill. I’m thinking of a
miniature hammer drill similar to it’s big brother used to drill
concrete. Anyone know if such a device exists or should I add it to
my never ending project list?

Rick Copeland
Silversmith and Lapidary Artisan
Rocky Mountain Wonders
Colorado Springs, Colorado
http://rockymountainwonders.com

Are they doing it with an ultrasonic drill? Would think that’d be
the fastest/most efficient method for production work. Sure wish I
could afford one!

Andy, There are other technologies out there. CAD/ CAM can and will
do some of these jobs. But generally not with the machines in use for
the production of waxes. DO NOT TRY THIS YOURSELF IT MAY DESTROY
YOUR MILL!!! Laser can work for some stones. Special lasers not
welding lasers. And only on stones with certain properties. Like no
metallic inclusions… The far more widely used is ultra-sonic
cutting. The same is used for production inlay, agate cameos (see
Rio Grande) etc.etc.

Many levels of power are available. The, weaker ones are mainly good
for small hole drilling only (beads) and tend to work fairly slowly.
One needs to take many things into consideration when making the
necessary tools for the job. But pretty much any stone up to corundum
can be cut with 3d relief (think of a playdoh mold.) Initial setup
can cost a few hundred dollars for pieces like cameos. Hope this
helps. I have a larger unit and in the past we have milled
successively. Generally a run of a hundred or so can start to be
pretty cost effective.

Rob

Andy

How are these beads getting drilled, by what method--and where--and
by whom? 

Good question, and yes it sounds tough, but it is not. For those who
do thousands, setting up machinery to do it is very expensive but
they probably do it as a job shop for others too. I do all my own
drilling and have since the beginning, it is not difficult, just
practiced and seldom have I ever had anything take over a minute or
two. But, if I were doing thousands, I would send them out.

Terry

Rick…I would not recommend using any sort of ‘hammer’ device on
turquoise. Stick with the simple diamond drills, although I would
spend the extra bucks and get good sintered drills…not the cheap
plated ones.

Any vibrations on turquoise could result in crumbling…even more
than it might on other stones. Turquoise has so many internal flaws
(which may not even show on a polished stone) that I would not
attempt it. A simple reciprocating drill that automatically moved
inand our of the hold being drilled is ok. But no hammering please.

Cheers from Don in SoFL.

I have some turquoise nuggets that I need to drill. Drilling
turquoise shouldn't require an ultrasonic drill. I'm thinking of a
miniature hammer drill similar to it's big brother used to drill
concrete. Anyone know if such a device exists or should I add it
to my never ending project list?

Depending on how many nuggets you have, I have drilled holes in
turquoise by dipping the nugget in water and just using the water on
the surface with any diamond bit, best is diamond triple ripple bit,
going slow, dip stone repeatedly about every 3 seconds to clean out
debris. Start hole with bit at 45 degrees. Regular drill press works
fine, just vary pressure, press down, back off, press down, back off
to allow water to clean debris from bit and hole. Use piece of wood
under rock both just under water. Slow, light touch.

Richard Hart

See: http://www.lopacki.com/howto

The drilling of these small holes is classed as “deep drilling” ( a
hole more than 3 times the drill diameter). Holes of this type in any
material require “peck drilling” which backs the drill out at least
every 3 times the diameter or a little sooner… The drills of
whatever type require constant cooling lubrication and hole flushing
each time the drill is backed off. Stones should be fastened to a
piece of glass or similar stone with glue or dopping wax. This helps
prevent shear spalling when the drill goes thru the back side. This
will be the biggest problem. Use a drill press similar to the Foredom
one described by Daniel Lopacki. Freehand drilling will often not be
successful.

Don’t even think about conventional hammer type rock drills.
Practice- practice- practice.

jesse

Don't even think about conventional hammer type rock drills 

I’m guessing this is my reference to my comment about a non-existent
(to my knowledge) mini hammer drill. I was merely thinking out loud
as an alternative to expensive ultrasonic drilling equipment. BTW
I’ve been experimenting with a vibrating engraving tool with a
hardened steel point used to mark steel tools. It won’t drill a hole
in Turquoise as is but shows some promise as a component to my mini
hammer drill project.

I have not failed. I’ve just found 10,000 ways that won’t work.
Thomas A. Edison (1847 - 1931)

Rick Copeland
Silversmith and Lapidary Artisan
Rocky Mountain Wonders
Colorado Springs, Colorado
http://rockymountainwonders.com

I would not recommend using any sort of 'hammer' device on
turquoise. Stick with the simple diamond drills, although I would
spend the extra bucks and get good sintered drills....not the
cheap plated ones. 

I’m not sure if I have tried sintered diamond bits yet. Thanks for
the tip! I need to order some lapidary supplies and will order some.
Believe me I know about fracturing turquoise. I’m trying to drill
Cripple Creek Turquoise which is harder than your average turquoise
and is natural (not stabilized). I’m able to drill it fairly well
but I’m looking to improve the process so my wife and daughter can
take over the drilling as they are the ones doing the stringing. I’m
not looking to compete in the turquoise drilling market. I’m just
trying to offer quality turquoise beaded strung jewelry to my line
that is truly handmade (tumble polished, drilled, and strung) and not
just purchased and strung.

Rick Copeland
Silversmith and Lapidary Artisan
Rocky Mountain Wonders
Colorado Springs, Colorado
http://rockymountainwonders.com

Rick;

An inexpensive lapcraft Diamond drill will drill Turquoise very
well in a flexshaft or even better in a dremel moto tool, the drills
come in sizes from 1 mm to 3 mm and aren’t (or weren’t) but 3 or 4
dollars each. Just keep the turq, under water, I used to drill
stabilized nuggets with a Covington drill press and plain high speed
steel drill bit usually size 56, used to get $.02 per hole not
counting the ones in my fingers, Cheap contractors you know.

Ken Ferrell