[thuffner3]

Hi Ron,
Last year I built my own first furnace, (propane). I've cast several succesful pieces. One of the things I did learn, was to attach in such a way, a larger spru opening of sorts that was not foam. I.E.
I would bury my created piece in loose sand and as my sand reached the top of my piece impose an alum can with the top and bottom cut off. to sort of act as a super spru. What I believe this did was to force the gas from the foam out thru the sand and not back up the spru, thus causing my piece to be flawed by haveing the molten metal be forced back up the spru by the gas so to speak. I've have many more failures than successes, but this method also exacerbated the desire to build my first CNC carver/engraver. To remake all the pieces I'm trashing. Right now I look at this way, as long as I can get the surface I need milled,lathed or otherwise to the place I need it. It does really matter what the rest of it looks like. Sorry for the rant.
If I can be of any help in this method of casting please feel free to drop me a line.

Peace
In GOD
Neil

MERRY CHRISTMAS.