from the old forum:
Experiments with fluxes, for ladling.Powdered Charcoal
I use a food processor to grind bar-b-q charcoal into flour. The finer, the better. About one tablespoon per 10 pounds of lead. It works OK, no smoke, and only a little bar-b-que odor. It would be the perfect flux except it takes a lot of lead out with the dross. For this reason I will only use it for wheelweight but not for expensive or hard-to-find alloys (the lead used for testing molds gets recycled over and over so the flux loss adds up over time. For normal use the flux loss would not matter much since you would only need to flux once per pot). Note: the food processor was eventually destroyed while grinding charcoal, so that was the end of the powdered charcoal flux.Olive or canola oil
Dispense with a pump bottle like used for hand soaps. About one teaspoon per 10 pounds lead. It fluxes very well with minimum waste. It does smoke, but the smoke and smell are not as bad as other waxy or oily fluxes. It does not catch fire unless the pot temperature is very high. Works better in combination with fine sawdust.Cornmeal
the most effective flux I have tried. Very aggressive. This would be good for smelting wheelweight outdoors. However, the smell is very strong.Potato Flakes
OK but not as good as cornmeal and even stinkier. Burnt potato -- yuk! Fine Sawdust
not so great by itself but when good when combined with olive oil or beeswax. Some woods like oak will have a pungent odor. Do not use dust from particle board or OSB because the binders may be toxic.LBT bullet lube
is a pretty decent flux, with a pleasant smell. That is the only use I have for LBT lube.Borax
seems to work at first but takes a lot of good lead out with the dross. I think Borax is an oxidizer and actually oxidizes good lead. It does not smoke or stink much and it does get the pot clean, but the loss is unacceptable.Beeswax
works well at low temperatures, smells bad at higher temperatures. Improved by adding fine sawdust.
I have yet to find the perfect flux. They all smell bad, some are just worse than others.