A fellow I used to see on my meter reading route said he used borax, the 20 mule team stuff for bullet fluxing. He had been casting for over 50 years and said he was told to use it By someone in the Lyman factory. No smoke no smell just white powder where he spilled it. I was wondering if anybody else uses this stuff and if so how much. Thanks

257 Rock,
I use whatever wax is at hand for intial fluxing of a mix, but then put an inch or so of crumbled charcoal on top of the mix. Voila' no more fluxing needed. I'm a ladle caster as well, using a Rowell #2, this has the feature of a 'tube' to the bottom of the ladle bowl. A full scoop holds ~ a pound of molten metal, I can do a 6 cavity 245gr mould with one scoop, the bit of charcoal on top of the ladle keeps oxygen out of the mix, and helps hold the heat. The hot charcoal prevents contamination, or 'burning' of the tin, and keeps noxious gases and fumes to a minimum.
Cheers,
R*2

I use plain unflavored kitty litter on top of my bottom pour pot. Learned this from one of the guys on the old Shooters Forum.

quote:

Originally posted by Jimmy Mac:
I use plain unflavored kitty litter on top of my bottom pour pot. Learned this from one of the guys on the old Shooters Forum.

Jimmy,
Try the charcoal, because it's actually 'burning', it becomes an active chemical seal, whereas the inert kitty litter is just a physical barrier.
Cheers,
R*2
Ps. This was a tip from Bill Ferguson "the antimony man", works good! He's forgotten more about lead and alloys than most will ever know. www.theantimonyman.com

The problem with borax is it is hydroscopic, ie attracts water, and when you stir it in your mix, you'll get sizzling and popping. It seems to coat your mixing spoon with a film, which soaks up moisture, and releases it when stirred in.

I use wax, but will have to try charcoal, as that sounds like the best way to go.

I just tried Borax for the first time. It does work. It doesn't stink -- well, maybe it makes your casting area smell like a laundromat. It does contain moisture and it does sizzle and pop, but just enough to agitate the melt, not enough to cause problems. It does seem to react with the lead and produce a significant volume of some kind of ashy grey product, which is then skimmed off.

I'll use it for a week or so and then report back.

Bullet casting metal is fluxed not to clean the metal but to remove the oxygen from the oxides that float to the surface.

Borax(Hydrated Sodium Borate) is hygroscopic
(absorbing or attracting moisture from the air)
it has 8 atoms of oxygen in the compound therefore it could not react with oxides from lead or tin .

Borax is a good flux for brazing,it is melted onto the surface to be brazed forming a crude glass which excludes the oxygen before oxides can form.

Kitty litter(diatomaceous earth)is siliceous in nature,I'm not sure if it would combine with the oxygen. A layer of it on top of the alloy would inhibit the futher formation of oxides.

The flux needed for a lead and tin alloy is carbon.Carbon reacts readily with lead and tin oxides reducing the oxides to metal with CO and CO2 gases as by products.

Powdered charcoal works well because it doesn't burn off as fast as oils or waxes.

WC

Thanks for the replys and reasons. I have always used some wax but wondered about this borax thing. I will most likly try it sometime just so I can say I did. Do you just break up some of the charcoal you use for grilling or is it something different.

quote:

Originally posted by 257 Rock:
Thanks for the replys and reasons. I have always used some wax but wondered about this borax thing. I will most likly try it sometime just so I can say I did. Do you just break up some of the charcoal you use for grilling or is it something different.

257,
Ayup, ordinary old charcoal outa' the woodstove, fireplace, or grill.
Thanks for the input Wildcat, and a bit more of the science of what's goin' on.
Cheers,
R*2

Charcoal sounds like a good idea but I don't have any easy way to pulverize briquets, and don't have any other source.

Seeking a fine grained, carbon-rich material, I tried cormeal today -- worked great, but it did smoke a little, and smelled like burnt popcorn. Next time I'll try tater flakes.

Wildcat's info got me thinking. The other day when I tried borax, I put in about 1 teaspoon of borax and took out about 1/4 - 1/3 cup of grey crud. I'd never seen so much crud come out, cuz the pot wasn't that dirty. Maybe the oxygen in borax was oxidizing the lead???? It did a great job of cleaning the pot, but I may have lost a lot of good lead in the process.

[QUOTE]Originally posted by popenmann:
Charcoal sounds like a good idea but I don't have any easy way to pulverize briquets, "

pop,
No hammer??????????? Rolling pin? Wack it with a shoe!
R*2

]

When I was a schoolmarm, I collected pencil sharpener shavings for use as a blanket on the melt. I would detail a boy to gather shavings from all the rooms each semester when new pencils were distributed and got lots. It turns to charcoal quickly enough. The graphite was no problem as it skimmed off to make incredibly dirty hands.
The shavings monitor was allowed to sit in the corner and make himself lead soldiers, fishing sinkers and bullets at lunch time as a reward.
Had lots of volunteers.
Cheers from Darkest California,
Ross

Today I tried tater flakes (don't laugh, about a year ago another poster on this board highly recommended using a chunk of raw potato). The tater flakes worked very well as a flux, much like the cornmeal I tried the other day. Residual moisture in the flakes made it sizzle and agitate the melt, which is good up to a point. There was a little smoke, not as much as with wax or oil, but like the cornmeal the smoke smell was very unpleasant and lingered for a long time, making tater flakes unsuitable for indoor use.

Tomorrow I will try flour. Maybe I could find an old coffee grinder and use it to pulverize charcoal briquets .....

We do quite a bit of woodworking here so i make my own charcoal by sprinkling sawdust on the melt.

Why not try coffee grounds, either fresh or recycled and dried? I know they will give off a lot of smoke. I use Brita water filters and am thinking of drying out the charcoal in old filters and trying that. I have a second small house on my property, currently being modified into a work shop. The kitchen has a small electric stove which I covered with a piece of sheet metal and set my electric melting pot on. Above the pot is an exhaust blower (to outdoors) and light so it's a nice set up and keeps the fumes down. I do my initial meltdowns (of scrap and wheelweights) outdoors over a Coleman gasoline camping stove and stir in chunks of old candle wax which give off clouds of smoke before bursting into flames. To the uninitiated it looks like alchemy.

Coffee grounds? At least they should smell nice. Unfortunately, I don't drink coffee.

Today I tried flour. It worked, though only so-so. It smoked just as much as wax, though, so scratch flour off the list.

I suppose I'll have to try the charcoal, otherwise I would go through life wondering if I'm missing out on something good.

If the charcoal doesn't work out, then I may break down and buy Marvalux. I cast indoors, with no ventilation in the winter (which lasts 9 months here).

Experimenting is half the fun of casting.

Some years ago when Linotype was still used in the Newspaper industry . The method of fluxing was using Potatos. It is a method I have used for many years and to date have had no problems

I must be honest and say that I've never cast or been involved in any casting. But in reference to your charcoal problem, you might go to your nearest pet store that carries tropical fish supplies and pick up the charcoal for the filters that they use. Not sure how much you need or how long it lasts, but it comes in pretty small granules and should be available in like 1-3 lb boxes. Might be worth a look-see.

284Win,
Thanks for the tip. I might pulverize it my food processor to make it even finer. It should wash up OK.

Update on charcoal:

I checked out the fish tank filter stuff, about $4 for an itty bitty box. It might have been worth it except it appeared to be coarser than I wanted.

So I bought a $4 bag of bar-b-que charcoal instead. 4 briquets go into the food processor, after several minutes out comes a nice black flour. Next time I'll grind it outdoors, instead of in the kitchen.

I tried it a couple of times today. It does act as a flux, not very agressively, but adequate. Only a little smoke and very little odor. After a couple of minutes it turns grey and clumpy. One spoonful of charcoal flour yielded 3 - 4 spoonfuls of grey gunk. It made me wonder if it was actually oxidizing the lead similar to what the Borax did. So far it's looking pretty good, but I want to use it for a while before I make up my mind.

I gotta ask...what did your wife think of the fine black dust all over the kitchen?

3584Elk,
Being single does have its advantages.

The second time around, the gears stripped on the food processor, so now I am back to square one. I do like the finely powdered charcoal as a flux, but there needs to be an easy, economical way to grind it.