Steve I agree 100%
I flux 2 or 3 times on a 20 lb pot. I use gulf wax and ignite it while stirring the mix while scraping the bottom and side aggressively. All the "crap" is released and floats to the top to be skimmed off with my tea strainer. Lead goes through the strainer and the dross stays out to be dumped. Once you get to the point where it's just oxidized lead it's obvious you're done.
Once two metals are alloyed, they are molecularly one. There is no settling of the pure lead and floating of the lighter tin or zinc or Linotype (which is another alloy itself). It's not like water and oil.
I'm no expert, this is just my understanding.
Last edited by Rigmarol; February 6, 2013 at 09:08 PM.