What kind of flux do you prefer and why

[ballistim]

My table saw is about 20' away from my smelting set-up, kinda made my decision pretty easy to try it, has worked better for me than anything else. I also use paint sticks or cut myself stirring sticks from scraps when using my table saw, and save all the sawdust for smelting, both pine & hardwood, both work well for me. Stirring with a stick is dual purpose as it cleans the sides & bottom of the pot while adding carbon so its a win-win situation.

[btroj]

Be careful scraping the bottom of the pot with a stick, it is easy to get bits of charred wood stuck in the valve. Been there, done that. I no longer stir with a stick for that reason.

[ballistim]

Be careful scraping the bottom of the pot with a stick, it is easy to get bits of charred wood stuck in the valve. Been there, done that. I no longer stir with a stick for that reason.

So have I! I only do that now in my large smelting pot using a ladle to pour into ingots. I use a layer of sawdust on the surface of my Lee 20# pot when casting to prevent surface oxidation. Good advice on the stirring on the bottom of a bottom pour pot, had to drain a full pot when the valve stuck-no fun indeed!

[wmitty]

Used pecan hulls last couple of casting sessions for fluxing and they worked great.

[jmort]

I am all for thrift, but in my opinion, when you have pine pet bedding or pine kitty litter available for so little, why resort to anything else? I doubt anything will work better for smelting and most everything else will be less effective. If you cannot afford $4.00 to $7.00 for a lifetime supply, I understand.

[geargnasher]

I use kingsford's. Wood charcoal ("real") never crossed my mind. I don't see the issue with having it "burn down to carbon". It IS carbon, when it burns down it is ash. Ash is only good for keeping the air away from the melt's surface. The whole issue with all of this is to use something chemically more "active" than lead (and antimony and tin) that can wrest the oxygen off of the lead (etc) oxides. Carbon works, and is available. Other thangs will also work, but all of the common reducers contain carbon, and there are a truckload of alternatives. In the present case compare the charcoal to a simple piece of wood used to stir the melt. It fluxes as it stirs. The wood burns due to the heat and takes the oxygen away from the lead. It's the burning down where the fluxing happens. Once burned down the carbon is all turned into CO2.

You're talking about reducing, not fluxing. Anything will reduce. Wax, oil, resin, anything that will burn and support the exchange of electrons that shift oxygen atoms from one compound to another. the carbon is to remove UN-reduced oxides of zinc, aluminum, calcium, etc. out of the melt. If they're reduced too and already in suspension, you aren't getting them out again with carbon until they re-oxidize.

Gear

[gwpercle]

I am all for thrift, but in my opinion, when you have pine pet bedding or pine kitty litter available for so little, why resort to anything else? I doubt anything will work better for smelting and most everything else will be less effective. If you cannot afford $4.00 to $7.00 for a lifetime supply, I understand.

Don't get so frugal that you try used kitty litter (as in used by the kitty) that's a smell you wont soon forget. I know there is probably some chemical compound in kitty urine that is good for fluxing but you have to draw the frugality line somewhere.

[prs]

I "think" Kingsford charcoal is compressed of wood product AND bituminous coal. You can buy true wood charcoal of various quality. Vegetative matter like sawdust or nut hulls that have not been pre-charred should perform better as the charring process will pull oxygen from the metallic oxides and the resins in them (that will be lost in the charcoal process) will help bind the impurities.

On the lighter side, try marijuana buds. Wow, man, like, that really -- uh, er, what were we talk'n 'bout?????

Rooster

[geargnasher]

I don't know, but suddenly I'm craving Chee-tos and I don't know why.

Gear

[leebuilder]

Too funny. Used some potato chip/crumbs from the bottom of the bag once. Worked great, took me a while to figure out how fluxing works. I use saw dust and wax scraps, you just have to let it work with stirring and scraping.

[leftiye]

You're talking about reducing, not fluxing. Anything will reduce. Wax, oil, resin, anything that will burn and support the exchange of electrons that shift oxygen atoms from one compound to another. the carbon is to remove UN-reduced oxides of zinc, aluminum, calcium, etc. out of the melt. If they're reduced too and already in suspension, you aren't getting them out again with carbon until they re-oxidize. Gear

Sounds to me like everybody else is talking about reducing too. "If they're reduced too" they aren't oxides any more. True fluxing is simply an aid to skimming (think Marvelux).

[btroj]

Actually, sawdust does both. It chars and burns on a low order producing lots of carbon monoxide. Carbon monoxide is a great reducing agent. Once the wood chars it forms a substance that has lots of capability to adsorb things, things like the stuff we want gone. It holds on to them so when we skim he charred remains of the sawdust we also remove the impurities.

A wax does the reducing but it doesn't adsorb anything. Marvelux just removes everything, no reduction.

With a substance as cheap and universal as sawdust why use anything else? Well, technically I am using pet bedding but same thing essentially.

[cajun shooter]

I have like most tried a bunch of different things to use as a smelting flux. The best by far has been wood shavings, not sawdust, The shavings form a very good carbon pile that will clean anything that I've ever smelted. A member on this forum sold boxes of the stuff until a family problem put him out of business. His shavings were from spruce and they gave off a great smell. Later Fairshake.

[Smoke4320]

Cedar dog bed shaving work well and to me a great smell
a huge bag (many years supply ) will cost $4.00 to $8.00

[jmort]

I would research Cedar smoke before inhaling/enjoying it. My conclusion, Cedar shavings not for me.

[cbrick]

For those that like to use a wood stick to stir and scrape the sides/bottom of the pot here's a word of warning. Your intent is to flux, i.e. clean the alloy however that stick will char under the surface, the charred pieces can/will flake off under the surface and become trapped there. They then go out the bottom spout or get picked up with the ladle and cause inclusions in your bullets. Yes, the charred pieces are much lighter than lead but lead is dense enough to trap and hold them under the surface.

Stirring flux around on the surface of the melt will do a fine job of cleaning the surface of the melt but will do nothing for all the rest of the alloy in the pot. Proper fluxing means using a ladle or spoon to bring the alloy up to the surface and pouring it through the flux and continuing to do so until all of the alloy has been cleaned. Proper fluxing takes time & patience to be done correctly and done well.

Rick

[georgerkahn]

I concur with cbrick (Rick) re methodology; I use a two-step procedure: Step ONE is when I take wheel-weights and "whatever" which is melted over propane in my DCROCKETT pot -- where I vigorously flux with pine sawdust from under my table saw. The results are poured into ingots. Step TWO is when I'm preparing to make boolits, where these ingots -- plus RotoMetal tin and or super-hard is added -- all in an RCBS Pro-Melt, where I again flux with Marvelux and a bit of the red carnuba wax on Gouda cheese. This works for me...
georgerkahn

[JWFilips]

My procedure: Super clean the alloy ingots with flux ( sawdust) a number of times in the smelt. Then only these clean ingots in the bottom pour pot with only the use of a redutant ( bees wax) to get the tin back in... No carbon No Wood stir sticks = perfection in the dropped cast boolits....Very simple Very easy! I learned this from the "Masters" here! Yes and **** can get easily stuck in the bottom of the pot under the weight of the alloy! It does not come to the surface easily!!! Once you know this you will learn never to put **** alloy in your pot nor stir the bottom of a bottom pour pot with a carbonized stick!

I just love the way this site censors stuff! Krap is close to **** There is a lot worse here!

[cbrick]

We concur right up to and right before you mentioned Marvacrap. Anyone tried to bring any of that onto my property much less into my shop there will be a heck of a fight.

Aside from being extremely hydroscopic, aside from how horribly it gunk's up the pot and all tools is the fact that it removes all and any oxidation at the surface. Zero reducing of tin or antimony or anything else, truly nasty stuff. I use sawdust in the smelting pot and in the casting pot. Cleans and reduces. No, sawdust in the casting pot will not cause inclusions in your bullets unless you do something intentional to force it below the surface. Stirring with a wood stick can/will do this.

Rick