Originally Posted by
montana_charlie
There are two (primary) occasions when we melt lead alloy.
1.) when we are breaking down 'scrap' to clean up the metal, combine into a single homogenous alloy, and cast into ingots for storage ... and, 2.) when we are casting bullets.
During '1' (most of us use the term 'smelting' even if it IS incorrect) a lot of us use wax of various kinds. It DOES seem to help the various components 'blend' together, and it helps 'gather' trash into a wad for scooping it out.
Since this is a 'blending / cleaning' process, it seems okay to say we are 'fluxing' the components that we are 'smelting'.
When casting bullets ('2'), we are dealing with clean alloy. So the only thing we might do is cause oxidised metal to re-combine itself with the molten alloy. This change in oxidized metal is called 'reduction', and reducing oxides is done with carbon-based materials.
That includes the waxes, but also includes 'wood' (and almost everything else on the planet).
Allowing the wood to char on top of the lead is good, and it's even better if there is a small fire to help take oxygen molecules out of the oxides. So, wood dust, shavings, chips, and even solid sticks (used while stirring) are commonly used for reduction.
A thick layer of the resulting ash can be left on top of the alloy, if using a bottom pour pot, where it helps to keep atmospheric air away from the surface ... reducing the need for reduction. (pun intended).
By the way, it's not unusual to hear this reduction process also referred to as 'fluxing', so don't get confused.
A person using a dipper will probably skim all of the ash off and make bullets until dross (oxides) build up enough to clean it again.
Almost anything will work, but anything that will melt (unless it's a wax) is probably going to leave a mess.
CM