reading the prior posts is it correct that the frosting come from a higher heat?
Yes. That's it. Lots of heat, really just a tad too much. Just below frosting is where I was trying for, but I don't have a really stable pot and I wasn't using my thermometer.
Does it affect the BHN much?
Not at all. As long as the mold stays roughly the same temp.
The alloy can go from 750 to 950 and it won't matter.
, if you let the mold temps go up and down crazy-like, it will affect not only bhn but size as well.
From what I've read..... up to 3 bhn numbers on the hardness scale.