What happened here?

[Rasper]

I am finding that I need to burn out even these small test molds for more than 24 hours. The last one I poured, I burned out for 48 hours and it is the first one that was actually chalky white with no wax residue visible in the pouring cup. They are 12 inches tall and about 9 inches in diameter.

Richard

[Rasper]

I poured the next test yesterday. The casting is an exact replica of the wax, down to the tiny pin holes. Burning out longer has made a huge difference. One more test is coming up, and photographs of the results of all of the tests will come maybe tomorrow. Stay tuned.

R

[F.C.]

Good ya got it ironed out, Rasper.... happy for ya. Glad I could be of assistance in the theorizing department.

[Rasper]

All of these have only been cleaned up with a wire wheel.
Here is the first test. Insufficient burn out—24 hours.


This one using only fine brick dust and plaster as a brush on investment. No gas induced rash but a bit of a sandy rough surface. Burned out 48 hours.


This one is an exact reproduction of the wax. (Poor photograph.) I used fine brick dust, silica flour, and plaster. Burned out 48 hours.


Richard

[latzanimal]

Glad you git things ironed out Rasper...

FC I wish you were closer to me, I'm still looking to cast a cylinder...

[Rasper]

I re-poured The New Girl yesterday. Much better. I poured it a bit cooler, and I used distilled water in the initial coats of brushed on investment mix.



I did her lower leg separate this time to avoid core problems.

Richard