What's the proper way to mellt scrap metal?

[Shaun750]

I've been melting silver and gold for over 15 years,but had a terrible time the other day,melting an ingot.It was for a pendant 60mm x 30mm 1.5mm thick. I had to remelt it 3 times,and there was still a hole after rolling it down,that I had to solder.

When I think about it,I was never really told how to melt metal,Just shown it vaguely and then got on with it.

I've seen on ganoksin Giacomo melting silver filings and mixing borax and salt.I emailed him a while back,but didn't really find out what it was for.

Any of you guys come across,a more scientific method to melt metal.

[andrew_berry]

I make sure the scrap is clean and pop it into a crucible and melt it with a oxy/propane torch.

When you are heating the silver up, sprinkle with powdered borax.

Swirl the metal around as it get to look like mercury so any impurities get stuck in the borax coating the crucible. Sprinkle more borax on the surface so the molten silver is clean with no scum on the surface.

Pour into mold but still keeping flame on the pouring metal.

Cool gently.

Thats all I do.

Plenty of videos on YouTube showing how its done.

Andrew

[Shaun750]

Thanks Andrew,that's exactly what I've been doing for the years,but every now and again there is some quite bad porosity in the metal. The last time i did a big ingot,i had to repeat it three times before I got a decent melt, wasn't really that happy with the end result because i had to solder a hole in the metal.