Did you see Don Dunbar's statement on welding sand castings - can be difficult because of the silicone (sand) contaminating the surface.
A good heads-up IMOP.

George (down under)

Jack Beale wrote:

George,

    After reading so many messages, I just gotta tell 'ya: S-I-L-I-C-O-N-E... is used to make titties bigger.  S-I-L-I-C-O-N is the sand you refer to, and what they make computer chips outta...

    I believe that the sand (that's used in the mold) gets into surface of the finished piece and causes both welding and machining problems.

Jack Beale
jack.beale@att.net

 
The AirCraft Rotary Engine NewsLetter.  Powered by Linux.
ACRE NL web site. http://home.earthlink.net/~rotaryeng/            
Copyright 1998-2003 All world wide rights reserved.