about setting freeform In order to make the bezel,
he proposes to use substances which are
Alginate is the least accurate material used by dentists for crown
construction and is not used for that purpose by most dentists.
However having said that, it can work in the procedure you describe,
if handled properly. There are many other materials available for
taking the impression of your freeform stones which would work far
better without the dimensions being affected by time and humidity. As
to the high cost of the stone (Van Rock) which was suggested, there
are many manufacturers of dental stones (which is refined plaster of
Paris) which are equally hard. Since the volume available to purchase
is far more than you need, I am sure a visit to your dentist with an
explanation of your problem will result in him giving you on e or two
cupfuls of dental stone. They all have it for making models.
Does any of you uses this technique to set freeforms? If not,
which technique do you prefer?
I have made a complicated setting for a laser cut stone by
duplicating the stone using a polysiloxane impression material
(frequently used by dentists for accurate mouth impressions) and
pouring into the impression a plastic material instead of "stone".
This model was then mounted on the platform of a vacuum forming
machine (another dental tool) and a shell of acrylic is formed which
is the female counterpart of the stones pavilion. This is then
trimmed as desired and is subsequently cast in the desired metal by
investing it as you would a wax pattern and burning out. (good
I realize this is a rather sketchy desciption, and if further
is needed, please feel free to call upon me.
HTH JZ Dule