Has Anyone Done Home Silver Refining?

Been experimenting with the furnace and trying to practice on copper, but can't quite seem to get it hot enough to fully melt all the material I put in there... I know copper has a higher melting point than silver, but I should be able to melt it.... IR thermometer was showing around 2000F in the furnace... I got tired of blasting through all my propane today, just got a little nugget melted yesterday... not much to look at but it's a start... more experimenting on fuel/air mixture to come.... apparently this is harder than it looked!

Progress! Looking good!

Fun thread! Been looking for updates.

Excellent!

Impressive.

Jskirwin-

So far it's not cost effective, but a lot of that has been due to initial trial and error. I seem to have spent about $17 on propane so far for about maybe 3 pounds of copper melting, spread over three weekends. Now that I'm dialing it in I think this will get better. First couple weekends I had didn't have the gas flow high enough (mostly out of fear of the furnace capabilities), so I was just spending a long time skirting the melting point. This last weekend I had it cranked up and from start to being able to pour was about 45 minutes. After the initial warmup, I was able to pour, then add more to the crucible and have it quickly melt within about 10 minutes. So for cost effectiveness I'll need to spend a good chunk of the day melting, as I burn a lot of fuel just warming up.

Right now I'm more concerned with the fun of it and the hobby than being cost effective, but eventually I'd like that to change.

Have made some strides in being able to get more bars and better quality in shorter periods of time. My record so far was this morning - 5 bars in 1.5 hours. Also honing in how to get some of the finishes I want. I'm liking these pour lines. I rigged up a blowtorch to heat the ingot mold while I pour, so it cools a little more slowly and I get these circular ripples, otherwise the top layer cools too quickly and eventually sinks in like a deflated cake.

Have sold one on eBay for $8.50 plus shipping, hoping to eventually be getting more for these, but feeling out what the market thinks they're worth through auction. I have 10 more listed and each of them has a bid with still 5 days to go, so there's definitely some buzz out there.

My pressure regulator is just a knob that will go from 0-20 psi, so I can't tell exactly what pressure I'm using, but if I had to guess I probably have it around halfway at 10-15 psi. I'm going more now based on the sound of the furnace to know if it's cranked up enough.

I probably load up about 5 lbs of wire per pour. I fill it with wire scraps before putting it in the furnace, lite the furnace on a low flame, and put the crucible in there on low to let everything warm up for about 5 mins, then I'll put the lid down and crank it up. After that initial wire melts down I have some thicker 1" thick copper wires that I stick in there to add to the melt. I try not to get the crucible more than about 1/3 full, so it's not too heavy/awkward.

Using my IR thermometer, when the temperature is reading about 2100-2200F then it seems to be about ready.

I've also found that I can only run one propane tank about an hour before it starts to freeze and flow gets restricted, so I have 2 tanks so I can alternate. Not sure if that will still be an issue in the summer...