Both times I have cast a ring with a reasonably hollow ( domed ) head. I have calculated the metal needed carefully as I have done on successful casts. When I remove the cast rings there is no button and the space (hollow) on the underside of the dome is full of metal that I assume was for my button. A realmess!
Here’s my answer: Bob: Many things attribute to your casting
problem of a filled in hollow dome ring.
- Don’t skimp on metal, Usually good measure to put 50% more
metal in for melt than ring needs. 2. Try this procedure on
investing:
Dip waxes in a wax wash and let dry 1/2 hour before investing.
Mix investment for 4� minutes, Vacumn 2 minutes, habd stir with
a spoon 30 seconds, (will realse further air bubbles), vacumn
flask for 2 minutes.
The blob of metal underneath is an air bubble that gets filled
in as if it was wax. Your investment may be too thick and not
able to get underneath. Follow investment instructions, don’t eye
ball or add water or investment later because you think it looks
wrong.
If you have a large dome ring, maybe try dripping some
investment under the dome part, then qucikly placing the falsk
over it and filling it up.
Hope this helps.
David Geller