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First
the stone's diameter is measured at the pavillion and a dent is made in
the metal for the pilot drill (about 1mm diameter). Then the metal is
drilled through. The metal is drilled again until the hole is about 3/4
the size of the stone's diameter. Lubricate the drill bit. As long as
there is a 0.3 mm seat left there is enough to set with. It is an easy
mistake not to take out enough metal, 3/4 of the diameter of the stone
is probably a bigger final drill bit than you think. Hold it on top of
the stone to see how much stone sticks out on each side of the bit.
The seat is cut to fit the stone. This is done by using a drill bit (an
emergency measure only), or a stonesetting bur (which may tend to clog
from removing too much material, or tip and damage the setting) or a ball
bur which will stay centered no matter how one holds it and cuts easily
through the material. If one desires one can cut the seat afterwards gently
with the stonesetting bur. Some setters use a cone or flame bur and follow
it with the stonesetting bur. The tool is the same diameter as the stone.
Again, recommended procedure is first punch mark, then pilot drill, drill
to 3/4 diameter of stone, use ball bur to prepare seat for stone, follow
up with setting bur if desired. The cone bur can in an emergency be used
to "pull" the hole in one direction or the other before using
the setting bur to create the final seat.
Using a beveled graver one starts about 1.5-3mm away from the stone and
pushes down into the metal at a 40 degree angle, rising to a 45 degree
one. Note that is rather steep. The front of the graver pushes through
the metal and pushes the wall down against the stone holding it in place.
This is then done from the opposite direction and from the two other opposing
directions. The stone is now set and the raised material is now ready
for beading and rounding off with the beading tool which is used with
a slight sideways wiggle to burnish and polish the bead. One approaches
the bead at an angle slanted away from the stone, lifts the beading tool
up to vertical while pressing on it and then does a sideways "tremble"
with it to properly round the bead. It is important to understand that
it is the wall of the hole that moves in and holds the stone in place-it
is not the bead, that is purely decorative.
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