Sawdust as a flux??

[J-Bar]

I have been using canning paraffin to flux the molten lead in my Lee bottom pour pot. I read an article that said sawdust is better than wax.

How much should I use? Should I light it with a match, like I do with the paraffin, to prevent smoking?

Any guidance appreciated.

 

[rcmodel]

Sawdust works as well as wax.

But it smokes like the dickens unless you light the smoke and burn it off.

Myself?

Not much works better then recovered cast bullets with old bullet lube still in the grooves.

Just throw a couple in and flux away!
I also save bullet lube 'balls' I roll up with my fingers while cleaning up my bullet size & lube press dies.

It works good too.
And the bees-wax ones even smell good!

rc

 

[ADKWOODSMAN]

Old crayons also work.

 

[Kp321]

I have used wax, sawdust, and rosin but now use nothing but Marvelux. No smoke, no mess.

 

[41 Mag]

I use the sawdust to flux when I am smelting my alloy down and pouring ingots from my big pot. It works great and I end up with nice clean ingots to put in my bottom pour.

I use the paraffin to flux in my bottom pour so I don't take the chance of getting any of the carbon from the sawdust down into the spout.

I have before and while it didn't totally plug it up, it sure made it squirt off to one side. It was pretty easily cleaned out, but I would rather not have to stop during a nice going pour and do it again.

 

[luzyfuerza]

^ what 41 mag wrote. I've also been known to recycle used walnut shells from the tumbler as flux.

 

[Steve2md]

I use sawdust as the bulk of my flux when smelting, then a pea sized ball of beeswax for a final cleaning before casting ingots. I only use beeswax in my casting pot (bottom pour lee). it has had about 500# of lead through it since I got it, and it still doesn't drip. I may drain it and give it a cleaning anyways, but I don't think it really needs it.

 

[splattergun]

I use sawdust as the bulk of my flux when smelting, then a pea sized ball of beeswax for a final cleaning before casting ingots. I only use beeswax in my casting pot (bottom pour lee). it has had about 500# of lead through it since I got it, and it still doesn't drip. I may drain it and give it a cleaning anyways, but I don't think it really needs it.

This
What you need to flux is carbon. Different sources of carbon will smoke more than others. Burn some sawdust. How does it smoke and sputter? Compare a paraffin candle to a beeswax candle. The paraffin drips and smokes. The beeswax burns cleanly.

For the initial smelting I use sawdust and light the smoke. For final smelting I use beeswax. If my bees have had an off year and I get no wax for myself, I'll use paraffin.

 

[Schwing]

I still use paraffin myself. I have a ton of it from my wife's canning days. When casting, I usually flux once, stir really well and remove the dross and then immediately flux again and leave the grey dusty carbon junk floating on top while I cast. The layer of gunk on top prevents oxidation that prevents your alloy from separating. On a bottom pour pot, you just need to make sure you don't let the pot get too low or that garbage ends up in the works and plugs things up.

 

[frankenstein406]

Pet bedding is cheap, I think it was $7 for a big bag. I like the bedding over candle wax but still use both.

 

[Steve2md]

Forgot to mention, I get my sawdust from whatever wood projects I do. I empty the catch bags from my chop saw and sanders into a tupperware and just keep adding to it. I save the shavings and dust from my lathe too, but it's sometimes a bit coarse. I have heard though, that home improvement stores will give you sawdust for free if you take in a bag and ask for some.

 

[oldillini]

Forgot to mention, I get my sawdust from whatever wood projects I do. I empty the catch bags from my chop saw and sanders into a tupperware and just keep adding to it. I save the shavings and dust from my lathe too, but it's sometimes a bit coarse. I have heard though, that home improvement stores will give you sawdust for free if you take in a bag and ask for some.

We have a saw mill near us where you can get it by the truck load. Don't know how coarse it is.

 

[gpb]

I use pine pet bedding shavings for flux. I would advise staying with identified pine shavings or saw dust. Many hardwoods have toxins in them.

 

[JohnM]

I burn wood, so I always have lots of chainsaw chips.
I scoop up a bucketful as needed.
Does a great job and I leave a layer of ash covering the top of the melt.

 

[mtrmn]

Pine rosin pulled straight off the trunks of trees in my yard. Smokes a little bit but smells good.

 

[J-Bar]

Good stuff pards, thank you!