Problem Fluxing! Help!

[dmclark523]

So I've melted down about 200 bars of lead in my new setup, but i keep running into a problem:
I've been using Walmart Tealights to flux with. I take them out of the little metal shell, and make sure all I am burning is the wax itself.
Problem is, sometimes it flames up, and other times it doesn't. When it doesn't, it leaves a really messy smear of brown/black oil on top of the lead, which, I assume, is the wax.
It acts the same way water does when mixed with oil. Its very, very hard to fish out of the pot with my spoon.
I've tried to encourage it to burst into flames by giving it a little bit of flame from a torch, but that doesn't work at all.

Suggestions? Really appreciate the help guys!

[500MAG]

I tried those once and will never do it again. I spent a heck of a long time trying to get that stuff out. Try some sawdust, it works great. I keep some scap pieces of 2x4's around and run the jigsaw thru them to collect up sawdust in a small plastic container.

[dmclark523]

How does sawdust work in the pot? Does it flame up? Does it just char over? What should I expect?

[oneokie]

It reduces the oxides back into the melt, same as any carbon based flux.
Some kinds of sawdust will flame when the smoke is ignited with a flame.
It will char over, you want to leave this on top of the melt unless you are dipping.
Doing so leaves an oxygen barrier that will greatly reduce oxidization of the alloy. Using sawdust as a flux will also remove the wax residue from the pot walls.

DO not use treated wood sawdust or particle board sawdust. The chemicals used in those are toxic when inhaled.

[R.M.]

When it doesn't flame up, it's probably because your melt temp. is lower than the wax's flash point. I'd bet raising the temp a bit would get it burning.

[snuffy]

If that wax is not self-igniting, you don't have the lead hot enough. End of story! Get a thermometer so you know when you have around 700 degrees. Fluxing at that low temp is not working. Wax should throw a lot of smoke, then burst into flame by itself. When it does, the lead is hot enough for the fluxing action to take place.

[Daffy]

If that wax is not self-igniting, you don't have the lead hot enough. End of story! Get a thermometer so you know when you have around 700 degrees. Fluxing at that low temp is not working. Wax should throw a lot of smoke, then burst into flame by itself. When it does, the lead is hot enough for the fluxing action to take place.

Agreed.

[geargnasher]

Carbon/hydrocarbons don't "flux". They "reduce" when burned. This reverts the oxide scum to elemental metal, but doesn't do a thing to remove contaminants from scrap alloy, particularly dissolved metals and such that muck up the casting quality of the alloy. Sawdust contains carbohydrates, which (long story short) help remove these contaminants, as well as reduce the oxides, two-in-one substance. Stir it a lot with a wooden stick to expose as much alloy to the charring sawdust as possible.

Read Glen Fryxell's "The simple act of fluxing" (google) and you'll know all you need to know.

Gear

[runfiverun]

^^^^^^^^^^^^^^
didn't even read the post just do that.
if the wax don't light off throw a match in there.