Which is the right flux powder to use for melting scrap silver for casting?
Printable View
Which is the right flux powder to use for melting scrap silver for casting?
Whatever works.
I tend to use borax & charcoal; I'd try ammonium chloride if I had any on hand.
You must have a chemical cupboard stuffed full Peter. I do have borax powder - the kind you use for cleaning. Is that the same as you get with a borax dish? But I don't have ammonium chloride - where do you get that? Lots of sodium chloride, though.
Perhaps I'll have to buy a dedicated one - was looking at easy flo flux powder and tenacity, but the first had a low temp limit, and the latter said it had to be mixed with water. So I'm confused.
I have a bit of an assortment... I usually buy powdered borax from the local Chinese grocers (along with bicarb by the 3kg bag) - and borax is borax (sodium tetraborate decahydrate).
Easyflow & Tenacity fluxes I have around too; I only use them with Easyflow & Silverflow solders though.
Rose Chemicals might have ammonium chloride?
How do you mean clean?
On the Cooksons Knowledgebase it says you can just use Borax paste from the borax cone. I have only got one of the tiny scorifiers so is that OK or do you REALLY need borax powder?
The only difference between the borax I buy as powder and the borax in a cone is the cone is stuck together; they're both decahydrate (10 molecules of water to 1 of sodium borate). There will be a bit more water in the paste than there is in the powder, and that's it. But the water will be driven off at the temperatures you're aiming for!
Cheers both! :Y: