Throwing My 2 cents in here. I was the person who mentioned way back that I had tried direct Microwave curing and it did not work well.. I even kep the parts in a microwave running at full power for as much as 20 minutes. Diferent materials reacted differently, but none were castable.
Using the 50/50 mix , Mike's settings on a 1.2 machine:
My next experiment had been using water and a microwave. I would run the microwave for 3 minutes on with a tall jar 1/2 filled with water and 5 or 6 parts in the water. I would allow the water to cool down and run it again for 3 minutes , cool down and run again. I then tried direct casting and it was Sometimes good and sometimes not. I did find that I could cure the resin in a UV curing system with a rotary device to rotate the parts for 10 to 20 minutes and the pieces became harder . These cast pretty good.
My Next experiment which seems to work BEST is:
I bought Mineral oil from CVS and put that in the jar instead of water. WHY ?
Oil can reach higher temperatures then water as the water can only reach boiling temperature.
So, i put 10 pieces made of the 50/50mix into my Mineral oil jar into the microwave.
1st noticeable difference between water and mineral oil..
In water, air bubbles cling to the surface of the parts, probably creating some issues.
In Oil, there were no air bubbles on the parts.
I cured the parts in mineral oil for 3 minutes in a 700 watt Microwave on full power. This was so hot that you could not touch
the glass without getting a bit of a burn. I allowed it to cool down and did it again for 3 minutes. ( do not know if it was needed to do twice) I put small and larger parts into casting and they all came out perfect with no failures.
My reasoning is the Mineral oil gets absorbed into the material a little and helps cure it. Since the oil is a combustible product, this may help in the "burning of the resin" . I have done this many times and the results have been very good.
I suspect we could use other types of liquid that are combustible, but there could be a danger in that while microwaving... so far, the mineral oil seems to be safe running for 2 to 4 minutes at a time. I do not suggest running oil in the microwave for 10 to 15 minutes as that MAY have an undesired effect.
Dealing with mineral oil, you should wear rubber gloves. AIR BLAST Excess OIL AT THIS TIME using compressed air.All the oil will not be gone, so expect there will be some left on the pieces.
IF you leave the pieces out to dry overnight, in the morning, they will appear to have absorbed all the oil which is a good thing, but not necessary.
Also, to attach the wax casting sprue so it does not come off, first use your wax pen to melt some wax directly onto the part and allow it to cool. Then weld your casting sprue to that location. The reason for doing it this way is so the first wax melted can get hot enough and bond to the part through the oil coating. This makes it easier to weld the sprue to that area without it constantly falling off.
I have been developing different methods of curing because My factory also does large parts and we use all kinds of materials. Curing and casting larger parts can sometimes be problematic.