How much sawdust to add to lead as flux?

[ikevinlu07]

Hey! I just saw'd some hardwood logs for sawdust..
Now I need to know in what quantity of sawdust per pound of lead?

I have 50 lbs of lead sheets (x-ray room).

Thanks!

[MyFlatline]

I think the pine dust works better IMO. When fluxing cover the top of the pot with a thin layer, let it start to char and stir it in. Do it a few times and you will answer your own question..

Best of luck

[Grmps]

Similar to myflatline,
for smelting I cover the top with a good layer, wait till it starts to char then light it and wait until it burns off then stir it in well
for casting I do the same thing then leave it (the crumbly dross) on top to prevent oxidation and splash whe returning spues to the pot.

Hardwood will work, Pine is better due to the sap/resin in it.

[ikevinlu07]

Ah, thank you. I only have hardwoods in my backyard ;/

[MyFlatline]

If you have a lumber yard near, they will gladly give you a bucket of pine dust...just sayin

[lightman]

I start off with a big hand full, maybe like a coffee cup. The rosin in the pine seems to work better than other stuff, but throw a fist full into the melt and see what happens.

[MaryB]

If I am low on sawdust I grab a scrap of 2x4 and my chopsaw and start shaving the end. 5 minute and I have a small bucket of sawdust

[bbogue1]

I put a box under my table saw and collect the sawdust. Mostly pine, some fir.
When I smelt as soon as I start to see melt in the bottom of the pot. I sprinkle a generous handful over the soon to be melted lead. I begin stirring it in deep while I let it char and the lead melt. I'll add more every so often to assure no oxidation of the tin. Always stirring it in while scraping the sides and bottom of the pot. When everything is melted and I have stirred a little bit, After the slushy stage but, before the lead gets too hot I pour it into an ingot mold, At that point when I return the pot to the heat I will remove the dross. When the ingot mold has been filled I add more lead and sawdust and repeat the above actions. When I am done I leave about a quarter inch of lead in the bottom of the pot and the char stays also.

I use a different pot to smelt than I do to cast. My casting pot is a bottom pour pot. The ingots in the casting pot are subject to a handful of sawdust also just to keep the oxidation down. Less stirring but I do stir deep but not as often. The sawdust on top thins out as it chars so I add more now and then to keep the sprew splash down. A little lead (2-4 pounds is left in the pot with the char when I'm done. All the reject bullets go into the pot for next time.

[5Shot]

I go to the Farm & Feed store and get a bale of Pine shavings (pet bedding) for about $4.00

[kens]

My own belief is that the sawdust is a means to keep air (oxygen) off the lead melt. When the sawdust burns up and leaves carbon, the carbon ash is a neutral element that serves to block air from allowing the lead to oxidize.
Just my .02 cents

[runfiverun]

the ash is carbon and your doing a process called carburization.
this helps the alloy bind together better.
[this is a true fluxing]
don't just be jamming the ash down into the alloy or you'll play hell getting it back out.
just work the alloy through the ashes picking it up from the bottom and pouring it through.

then throw some wax in the mix and light it off.
this creates an oxygen free barrier on top of the alloy and is a true reluctant to return the oxides back into the alloy.

now you scrape all the junk off the top and smash it against the side of the pot.
as you cast just doing the wax and fire routine is generally enough to keep the oxides under control.

[ikevinlu07]

Thank you all for the advice. I will do ask you guys suggested.i

[country gent]

I use a medium hand full of pet bedding on my pot when fluxing and flux as needed my ladle casting pot is 100+ pounds when full. I let it char a little add a small bit of wax with it and stir it working the lead up thru it to help. I use a big slotted serving spoon or spatula to stir and scrape the pot. the slotted spoon removes most of the ash and debris and a solid one removes the rest.

[Scooby]

+1 for the coffee cup amount in my harbor freight dutch oven. The handle on the cup is nice to hold onto too.

[kens]

sawdust & wax works so well, that I must ask:
why isn't Marvelux made of sawdust an wax?

[308Jeff]

sawdust & wax works so well, that I must ask:
why isn't Marvelux made of sawdust an wax?

Floor sweeping compound is. I picked up a 50lb box at Big D Flooring. Works great.

[mac1911]

sawdust & wax works so well, that I must ask:
why isn't Marvelux made of sawdust an wax?

It would need to come with a heavy duty ventelation system.
I like wood shavings for the smell. Marvelux is great for the casting pot inside.

[jsizemore]

I used to make my own but I did some work with a guy that has one of those portable traveling bandsaw mills. He said come and get all I want.

[Bazoo]

I use pine bedding also, as we have a guinea pig.

[Budzilla 19]

We sawed up some 147 year old long leaf pines that had to come down, and I got a lifetime supply of really heavy with rosin sawdust! Works like a dream! Smells good also! Like a campfire!