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Firstly, this is the way I do it. There are MANY other ways
of doing it and amongst gem cutters, saying one method is
better than the other is like arguing about religion or
politics.
This is the method that works for me and I can't remember
when last a stone popped off my dop.
I use a 5 minute epoxy to dop the stone onto the first dop.
Since I come from South Africa, the glue of choice is
Pratley White, but Devcon works just as well.
So there are my two dops and a
post-it pad to mix the glue on and a toothpick (cheap and
easy) and two syringes filled with glue. This I do so that I
can dispense the glue easily and accurately.
The syringes that the (Devcon) glues come in are junk. As
you see, Pratley is different colors, so seeing that it is
mixed well is easy.
The syringe lets you dispense small amounts of glue and
because it is accurate, the glue bonds very strongly.
Like this.
I am dopping two peridots, but
not all the following pictures will have them. I culled this
tutorial from pictures of various stones.
After the pavilion is finished
I transfer.
So now I align the stones up properly. Unlike wax or
cyanoacrylate, I have plenty of time.
Now comes the trick. After the
epoxy has hardened, I use an oxygen/lpg torch, called the
little torch. I heat the dop at the base with a hot flame.
The heat races up the dop and hits the glue. Before it can
cross the glue and into the stone, it separates, because 5
minute epoxies fail at about 100C.
Now I am holding the stone in a parallel jaw pliers if it is
a square stone or a specially bent pair if it is round, tri
etc. I am giving GENTLE pressure on the soldering pad, so
that as soon the heat hits the glue the dop gives way.
I hold the stone firmly, not to hard so as to chip it. I
also had a set of pliers that had nylon lined jaws but some
one stole them. They are the best to use. However, is the
stone is very fragile, like some Smithsonite I cut the other
day, I hold the dops by hand.Works just as well...
One doesn't have to use a oxy/gas torch. One of those cigar
gas lighters work just as well.
Here they are separated. I
know this is an Afghan tourmaline. The peridots in the first
pictures are long time finished :)
Here are the pliers I use for
round stones.
And this is how I remove the
stone after I have finished the crown if it is not too
sensitive. Otherwise I turf it into some Attack, an epoxy
solvent, or acetone for a day or so.
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