I see you let your flask sit for several minutes while u melted the gold. the flask temp dropped right? also I see it didnt affect anything . is this true? you can still get results with lower flask temps?
You can, but it's better to have your metal already melted/melting and ready to go with a furnace when the flask is reaching the end of its burnout cycle. The way this video shows melting the metal is fine, but getting a furnace was the best thing I ever bought for casting. Way safer, more predictable, and less wasteful with gas and oxygen. I also thought it was weird that he added the boric acid to the flask after he had already poured the metal. I work in a commercial jewelry repair shop, we put the boric in with the melted metal first then pour it. The boric has to melt to create a flux coating, it's to help the metal flow. Adding it in afterwards is counterintuitive.
I'm just curious why you add borax on the top after you cast. I've seen other casters do this but it doesn't make sense to me. How does it help with the casting to put it on the button after the casting is poured? I'm asking because I'm starting to learn how to cast. Thanks!
It's called Dura-Bull vacuum casting machine. The same machine is also for sale on Amazon under different brand names. OrangeA is one of them. RioGrande.com is the most reliable source for jewelry related supplies.
It's called investment plaster, and when mixed with the proper amount of water, which is usually becomes about the consistency of fairly thin pancake batter, creates the liquid plaster casting that gets poured into the flask.
It's boric acid powder. When heated, it melts to create a flux coating on the metal, helping it flow better. The video shows him adding it after pouring, which isn't correct. You're supposed to add it to the molten metal, then pour.
You can get vacuum tables like that from RioGrande. They're a little over $1,000, but for all that they can do and what they come with they're worth it.