Smelting

[686]

is there a best temp. to aix your alow at? i am using 5 lb ww--5 lb range-- 2 lb liontype--and 8 oz 60/40 sowder. i will be using a 75 lb pot addind and taking out 30 lb at a time. 2nd question, if you have un known ingets and wanted to remelt them and thought zink might be it there, would you belt at 650 or so to let the zink float to the top? thanks

[454PB]

I did a little "spell checking" here, and I think this is what you asked:

"Is there a best temp. to mix your alloy at? I am using 5 lb ww--5 lb range recovered scrap-- 2 lb linotype--and 8 oz 60/40 solder. I will be using a 75 lb pot adding and taking out 30 lb at a time. 2nd question, if you have unknown ingots and wanted to remelt them and thought zinc might be in there, would you melt at 650 or so to let the zinc float to the top? thanks"

Some people use a thermometer for smelting, with the idea that keeping the melt temperature below 787 degrees will prevent zinc contamination. I don't, I sort them by inspection have never found a zinc weight. When I'm doing several hundred pounds at a time, I really don't want to fool with a thermometer. I suppose it's possible that one slipped by me, but I've never found any problem to indicate that. On occasion, I use a thermometer while casting, but mostly as a curiousity. The 36 years that I have been casting has pretty well determined the way I do things, and the thermometer only verifies what I have learned through experience.

If you decide you're going to use a thermometer to smelt wheel weights, I'd recommend you shoot for 650 to 700 degrees before filling your ingots. The addition of linotype and solder lowers the melting point, and who knows what might be in range scrap.

I did an experiment once to see if I could separate the components in an alloy, and it failed. I doubt that zinc contaminated alloy could be salvaged in that manner.

[Bob Jones]

I try to keep the temp low and start pouring as soon as the melt is good and liquid and the refuse is skimmed. I do that in case of zinc ww and it does work. Last weekend I smelted about 400 pounds of wheel weights and for the first time, mixed in with the clips, were four wheel weights that hadn't melted. I quickly scooped them out and sure enough they were riveted zinc weights that had slipped through my inspection.

I don't use a thermometer but the mix goes from "slush" to liquid pretty quickly. Once it's a true liquid you can flux and skim, no reason to go any hotter that I can see.

[parson48]

I'm fairly new to all this, having smelted a grand total of 2 5 gal. buckets of ww. In this brief time I have found 4 steel weights and 2 with a Zn stamped on them. They didn't seem to be anywhere close to melting when I scooped them out with the clips. I don't have a thermometer, but I keep an eye on the melt.
parson 48