Alternate for Dental Plaster

PFAFF2@delphi.com
Sat, 29 Apr 1995 00:35:31 -0400 (EDT)

> I have just purchased an 8" mirror kit from Wilmann-Bell and would like to
> make the tool using plaster and ceramic tile. Several attempts to obtain
> "dental plaster" from local sources has produced nothing but frustration.
> Can anyone suggest a source or alternative. Also , this technique doesn't
> seem to be covered in any of the ATM books. Any suggestions on method/
> pitfalls would be appreciated.
>
>___________________________________________________________________________
>_____
> Joseph Hetmanski jfh@att.rguxa
>
I use Ultracal 30 or 60 made by U.S.G. You can find it in a building supply store that sells plaster supplies to building contractors. This casting plaster has almost no expansion or contraction when it sets. The cost is about $20.00 for a 100 lb bag ( a little over kill for a 8 in mirror ). It sticks well to tile also. Next choice is Hydrocal them just cement.

The only info that is published that I know is in Advanced Telescope Making Techniques Vol 2. Bob Pfaff