Shaping opal triplets

Hey everyone Happy Holidays. I have a job from a store that I do a
lot of work for and I’m cutting opal triplets into an assymetrical
shape to inlay into a 14k pendant. I’m using diamond cylinder-shaped
burs, a lot of water, and light pressure. I’m wondering if anyone
has a trick for eliminating the tiny little pressure flakes that
occur on the top layer of quartz. I’ll probably be doing a lot of
these in future so any tips will be greatly appreciated as I’d like
to have none of these little dings in the edge, but going back and
slightly rounding the edge of every one adds to the amount of time I
spend on them.

Thank you.

Hi, are you using too coarse a grit wheel or lap, try a softer grit
or do the major grinding on a coarse grit and then on a softer grit
such as 600grit or 800grit. Sandpaper is quite good for this also and
won’t chip, most chipping on quartz or opal is caused by using coarse
grinding wheels.

Christine in the Ridge where summer is here and all the wild grass
parrots have lots of babies at my seedbowls.

Hi, are you using too coarse a grit wheel or lap, try a softer grit
or do the major grinding on a coarse grit and then on a softer grit
such as 600grit or 800grit.

Hi,

Usually an inlay is fit in slightly proud of the metal, ground down
flush, then fine-sanded to prepare it for polishing. This lowering
process should take care of the chippy edges.

If the inlay is to stay raised, it sounds to me like you’re using
too coarse a diamond burr. The entire lapidary process is a
trade-off: the initial coarse grits remove a lot of material fast but
leave a rough surface which then needs to be smoothed and made
suitable for polishing by working progressively finer. But the fine
grits cut slowly. There is no magic bullet which will cut both fast
and fine.

Cheers,
Hans Durstling
Moncton, Canada

I think the problem lies with being able to find cylinder or tapered
abrasive burs that are small enough(like 2.5mm and 1.5mm) and are of
a fine enough grit.these flat triplets have to be shaped with
several tight, inward curves around the edges to fit into the piece.
I usually order from Rio G. but I didnt run across anything when I
looked. Either too course or to wide to do what I need. I’ve got
more of these pieces coming in a couple of weeks so I need to find
the right tool. Thanks in advance for any help.

As I understood it, you are reshaping the perimeter of completed
opal triplets. I believe you run the risk of separating the glued
layers by exposing the piece to the vibration/shock of the grinding
wheel and the water/lubricant used. Unless the glue used is
impervious to the coolant, both factors may affect the outcome.

Good luck to you.

Pam Chott
www.songofthephoenix.com

I think the problem lies with being able to find cylinder or
tapered abrasive burs that are small enough (like 2.5mm and 1.5mm) 

Diamond burs are, of course, the best. But you can do a lot with
wood. As I said in another thread, “The Chinese carved all that jade
with bamboo tools…” You can use dowels, and just charge them either
with diamond grit or carborundum. You’d be surprised… I have a
line
of stone carvings archived on my website - they’re all polished with
wooden dowels…