Metal Casting Zone

Decided to try another lost wax pattern, this time I was trying to see how small a part i could make. A little dog bone.
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this is my diy vaccum chamber, just to let you know drywall joint compound doesnt degass for s@#$.
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At 30 in in vac I made a giant mashmellow, the bubbles just would not pop.

Ok here the end result, the wax pattern floated in the investment and tilted over, the part didnt have a proper vent for the air to escape. I wouldnt call it a failure though, i just learned a few things to put into my box of tricks. On a brighter note though the overall finish is exactly what I was hoping for
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thats a great effort. all tricks add to experience.

That looks pretty good for a first try with brass. Did you do the same burn-out as you did with the zinc pour. I liked it too, by the way. I thought it required much higher burn-out temps, up around 1200 F. I contacted Ferris for some info, maybe I can get a free sample.

You may try an L shaped sprue to feed the metal under the part to fill it from the bottom up, with small vents on top. Just a thought, I have no experience at lost wax.

Im sure the burn out temp is supposed to be about 1350 but I feel that is to burn out the wax in areas where it puddles in the mold and cant run out. This wax seems to melt out at about 275 deg f and vaporizes at 340 but will leave a black goo where it puddles.
I think this is why they recommend the high burn out temps, but knowing this you should be able to mold up the part to keep it from leaving wax puddles and get a good melt out in the kitchen oven when the wife is away

"While the wife is away" being the key. It's ok to burn the peach cobbler and set off the smoke alarm (that usually means dinner is ready ) but just burn something that only slightly noxious and we will have to pay dearly.
There was a video on youtoob of a guy doing lost wax out of an oven and his spit and sputtered, threw metal all over and flamed up. Just be Careful. I've thought about setting the investment on top of the furnace while I was melting the metal to burn out some wax and preheat the mold.
Ferris's site doesn't tell much about what is required for burn-out.