How
to drill accurate holes for Reversible-Pins:
Now it is time to drill the second row of holes
for the plastic Reversible-Pins.
Place the
copper wire index pin in position
as described earlier. Make sure the index pin
is held in position (a bent piece of wire with
yellow covering is shown wedged in between
the laser stand and the copper wire; however,
a small piece of heavy steel set on top of
the wire would probably work just as well).
Use
the first row of holes to position the
model so the second row of holes can be
drilled. Let the copper wire index pin engage
each die pin hole, this will automatically
establish the correct distance between holes.
As you can see in the above picture, the laser light is lingual of the tooth center. The light comes in handy for determining the mesio-distal location by rotating the model slightly.
As this picture illustrates, all of the plastic
reversible-pin holes are the same distance
from the die pin holes.
Glue all die pins in place
first, then insert the
plastic reversible-pins. Cut any index grooves
needed and lubricate the surface.
Reversible-Pins
are not glued, but inserted
securely
into the holes.