Smoke

[WHITETAIL]

I would like to thank the guys & gals here
for giving me many opinions on useing
sawdust for fluxing the lead.:grin:
I was smelting yesterday and tried
both wax and sawdust for fluxing.
Made a bunch of smoke, but it smelled
GOOOOOD.[smilie=w:
It seened to me that I got a lot more junk
out without taking much lead out.

[Bret4207]

Try stirring the sawdust with a stick, double the effect.

[crabo]

I like Home Depot free 5 gallon stirrer sticks. I pick up 5 or so when I pass through.

[fredj338]

I have used commercial flux, bullet lube, sawdust, it all works, but the sawdust & a bit of wax seems to work the best for me.

[archmaker]

I stir with a port orford cedar stick, I have a bunch that will not work well for my arrows, but the work very well for stirring the lead, and the smell . . . :)

[ra_balke]

Years ago I read in the CBA journal that Flux was good for nothing.
Once the alloying metals are combined, they do not seperate.

I dunno... .... that's what the journal article said.

Ever since them, I have not used flux even one time, I simply scrape most of the crud off the top, and do my casting outside in the open air.

[Heavy lead]

I know that if I do not flux I don't get nearly as good of mould fillout. I don't flux multiple times just once per casting session, but I do get better fillout no doubt.

[Bret4207]

Years ago I read in the CBA journal that Flux was good for nothing.
Once the alloying metals are combined, they do not seperate.

I dunno... .... that's what the journal article said.

Ever since them, I have not used flux even one time, I simply scrape most of the crud off the top, and do my casting outside in the open air.

I agree with what the article said, but- to me it seems the dirt and oxides in the pot, even dust in the air, tends to take some of the melt with it in the "crud" you're scraping off the top. Fluxing and stirring seems to reduce the amount of crud and garbage and make the melt cleaner. It also loosens what ever garbage is adhering to the pot walls and get's that floating to the top.

It seems to work, that's good enough for me. Like many things in this hobby the art aspect often seems to overshadow the science aspect.

[higgins]

Many years ago oiled sawdust was a recommended flux. If you ever want to experiment with it, don't go to a lot of trouble making it up. There is at least a small amount under the sprocket cover of your chain saw.

[Firebird]

The liquid metals don't separate out, they do stay dissolved in each other. What they also do is react with the oxygen in the air to form their metal oxides, which is what forms that scum on top of the liquid metal. Any flux that contains or burns down to carbon will reduce those metal oxides back into metal and carbon monoxide/carbon dioxide. A layer of kitty litter on top of the pot won't reduce the metal oxides, but will prevent the oxygen in the air from getting to the liquid metal. A lid on top of the pot will also help prevent the formation of the metal oxides, and also help keep heat in pot to melt the metal.

[Whitespider]

Years ago I read in the CBA journal that Flux was good for nothing.
Once the alloying metals are combined, they do not seperate.

Hmmmm..... I dunno if I can agree fully with the "good for nothing" part of that.

I wouldn't argue that "once the alloying metals are combined, they do not separate", but in my observations, fluxing does make the alloy somewhat more liquid, or thinner, flow easier, and that's at least something. As well, casting with a dipper (as I do) requires skimming the pot often, and fluxing dramatically reduces the amount of dross skimmed from the pot; again, that's at least something.

Is fluxing necessary? Maybe not. I know of one local that doesn't flux and the quality of his castings are not debatable. I've tried it both ways; I definitely see an improvement in flow (fill out) and the amount of waste (dross), which is enough to keep me fluxing.

[blackthorn]

There is an easy way to settle any doubt in your mind. Simply store up the skimmings from several pot fulls and then, later, put them into a separate pot and heat it up. Once it is good and hot add a bit of sawdust, oil, bullet lube etc. then take a very dry piece of 1x2 and stir the stuff really well. See what you wind up with. If there is no alloy melted/fluxed out you will know that fluxing does nothing! If there is useable recovery----well----