How much flux do you need for 1 lb lead alloy?

[Danm55]

New to making my own bullets. I didnt know u needed to flux the pot. How much parrafin should i add to the 1 lb lead? And do i just drop it in and wait for it to burn away completely?

[bangerjim]

Wax is a reducer. Saw dust is a flux!

Cover the top of the pot surface with about 1/2" or so of DRY pine sawdust and stir with a wooden paint paddle or stick. Remove burned wood when done after a few minutes.

The key word here is STIR!!!!!!!!!!!!

Now repeat that TWO MORE TIMES! That will give you clean lead. On the last fluxing add a bit of beeswax in to clean the mix. I do NOT ever use paraffin because it flares up way too easy and smells horrible. Beeswax is what works!

[Froogal]

I use sawdust for smelting range scrap into ingots. Just enough to almost cover the surface, and throw a lighted match on top. When actually casting bullets, I use candle wax. 2 or 3 thumbnail sized pieces to start, and maybe again when adding more lead

[TurnipEaterDown]

Wood / sawdust can make a very good reducing agent. When I was doing my MSME work on exhaust aftertreatment systems, at a school that had its history in mining, the Chem Prof on our team recommended that I look into copper mining & ore smelting operations to understand reduction reactions w/ copper compounds. The mills in the area in the 1800s used logs in the reduction furnaces to strip the oxygen from the copper ore. Copper ore (with lots of copper oxides) + wood (combustible), closed furnace at high temp, the wood wants to burn and will strip the oxygen from the copper ore to do so. Wood consumed, liquid copper poured off into ingots.

With the lead, same sort of thing is happening. Oxidized lead and desirable alloying materials (tin, antimony) can be de-oxidized (metal oxides reduced) by putting sawdust on the top of the pot when nice & hot and having the wood catch fire. Really helps if the lead is down quite a little bit from the pot rim, helps to keep the boundary between lead and sawdust depleted of atmospheric oxygen.
The sawdust will catch fire (I often find I have to light it) and since the fire is on top of the molten metal the interface will be depleted of atmospheric oxygen, and the hot sawdust will use what it can from the metal oxides.
Really, anything that burns good will work, just think about what you want to breathe, and listen to people who will tell you what works well. Like the two people already commenting did.

I remember melting down a couple hundred pounds of roofing lead one day at a friends farm. The tar on the sheeting did a right fine job of reducing the metal oxides, but the smoke cloud was horrible! Lots of black smoke from the tar, with yellow ash on the pot from sulphur, and a stink that was bad.
Same thing getting a couple hundred pounds of lead out of x-ray room wall sheeting. Buddy split up the wall sheeting and gave me the lead, which was covered in glue. Fired up the large pot outside on a nice windy day and melted it all down under a layer of ash from the glue. Neighbors probably wondered where the stink was coming from...

Like Bangerjim said, the waxes like paraffin will easily catch on fire and cause a hazard or draw attention.
The commercial casting fluxes as you can get from Midway or other reloading places work very well and are not fire prone (least what I have used), but you will pay something for them.

No matter what, as noted above, you should stir. Certainly makes the result better and gets you there quicker.

Enjoy your new hobby.

[pastera]

For smelting dirty lead, I use a tablespoon of plumbing flux for ~20-25 lbs more or less depending on the amount of dross.
Once that has reduced the dross, scrape out the dirt and junk - don't do this if you are trying to recover copper jackets unless you want them tinned with lead.

Do not use an active flux like rosin or acid in your casting pot - only in a cast iron pot. It will eat holes in a steel pot.

Saw dust or wood shavings are not very active so are safe to use on thin pots. However they take a higher temp and larger quantities to reduce all of the dross back to metals. I usually cover the pot and let it char for a while before stirring to eliminate any chance of steam and it creates the oxygen starved atmosphere necessary to get the last oxides to give up their O2.

[Hick]

Note that all the above is about cleaning the lead alloy of oxides and impurities. If the lead alloy you are talking about is already pure (such as from an alloy supplier) you won't need to flux much at all. When I use alloys like Lyman #2 from Rotometals I cast all day without flux and have almost no dross forming.

[justindad]

I don’t get good results from paraffin wax.
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In addition to sawdust & beeswax, I sometimes stir with a wooden stick (note: moisture in the wood steams out, which could be bad… I just don’t dunk the stick deeply into the lead). I have a block of paraffin & beeswax that was melted together, and I rub the hot stick on the block so I’m stirring in wax with the stick. Sometimes that turns the stick into a torch.
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I have recently been using stearic acid. Works very well at cleaning the top of the molten lead. Beef tallow probably has similar performance. The next block I make will be bees wax & stearic acid, without the paraffin.
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Lately I have been lighting the waxes & sawdust on fire after it warms on the lead. I like it so far.
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I do not put sawdust in the bottom pour pot, but I will use the stick in the bottom pour. I had debris in the nozzle and inclusions in the boolit when I stirred sawdust in the bottom pour, but I may have been doing something else dumb to cause that

[dale2242]

What works for me:
Put in enough dry pine shavings to cover the melt 1/2 " deep.
Toss in a fingernail sized piece of candle wax and ignite.
Stir until there is nothing left but ash on top of the melt.
Remove the ash with a perforated spoon.
Cast without inclusions. My melt is CLEAN.
I cast inside my shop. Igniting the smoke keeps the smell and smoke down.

[fredj338]

I only truly flux scrap when making ingots, sawdust & old bullet lube. Only clean alloy goes into my casting pot but I also toss back bullets during sizing that have a flaw & they are usually coated. SO I have a habit of stirring my casting pot with a wooden paint stick each time I add alloy. It seems to keep things running the way they should.

[JoeJames]

I use sawdust, and recommended it to a buddy who tried it. He had a real fancy area for his smelting; so he set off his smoke detector in his shop and back at the main house. His wife was not pleased.

[bangerjim]

I use sawdust, and recommended it to a buddy who tried it. He had a real fancy area for his smelting; so he set off his smoke detector in his shop and back at the main house. His wife was not pleased.

That is what he gets for trying to do dirty filthy stinking work like that inside! NEVER......EVER......ever! Remelting scrap/COWWs is an outside job.

Period.

banger