Cast Flux

[WFO2]

How often do you flux to take care of the oxidation during casting ?

[Shuz]

If you use a bottom pour furnace and float a layer of new kitty litter(diatamaceous earth) on top of your melt, you only need to flux at the start of operation. At least that works for me.
The kitty litter prevents air from getting to the melt and thus oxidizing it.

Those who ladle pour will have to weigh in on what they do.

[gwpercle]

I ladle pressure cast and fluxing is done when needed, I don't have any set time frame . Using a Lee Magnum Melter with 15 lbs. of clean ingots in there, I flux well when I start , then usually about halfway through the pot I flux again. Towards the end I will put back all the bad cast and sprues , melt and flux again and finish casting the metal. I like to keep the top surface clean so as not to pick up crud with my ladle.
I flux with three things, a small amount of Marvelux first , stir well and add a spoon of cedar pencil sharpener shavings to this add 1/4 teaspoon of beeswax and stir with a wooden paddle, skim and stir , skim and stir , till the top is clean and shiney . Sometimes I may have to flux one more time, especially if I add a few clip on wheel weights that are dirty . But a lot depends on how clean the ingots are.
I find this three way flux gets me the best mix.
Gary

[Bent Ramrod]

I flux at the beginning of casting and just push the accumulating oxidation out of the way with the ladle as I cast. I fill the ladle against the wall of the pot adjacent to the cleared area. By the time there is enough crud on the surface so this doesn't work, the pot is usually close to empty anyway. My pot is 20 lbs.

If I cast a lot of smaller boolits I might flux at the half-full point. But I try to do it as seldom as I can.

[country gent]

I flux somewhat often once I get everything going. My pot is 100lbs+ and theres ussually 2-3 of us casting from it at a time. Proably about every 150- 300 bullets total. I believe fluxing keeps the bullets more consistant due to a more consistant alloy mix. I read someplace once of an old time bullet caster ( 1910-1920 or so) that had an agitator made for his pot that constantly stirred the alloy while he was casting to keep it blended. I have thought about this since even on my big pot a auger type agitator would have to turn very fast to keep the metal mixed and moving. a power screw driver would do fine. I recomend fluxing as needed and as often as you feel it needs to.

[runfiverun]

maybe once a year.
seriously.
I put clean alloy in my casting pot and return sprues right from the cutter back to the pot.
I'm considering cleaning my pot for the first time since about 2004-5 or thereabouts.

[Yodogsandman]

I start each casting session with about a pencil eraser size chunk of wax or old bullet lube tossed on top of the melted alloy and light the fumes off with a wooden match. Stirring back in any oxides while scraping the bottom and sides of the bottom pour pot. Then any impurities are skimmed off and put into a metal coffee can. So, just once each session.

The small amount of oxides that show up on top of your alloy during a casting session doesn't change the composition of the alloy enough to worry about.

[HangFireW8]

I flux somewhat often once I get everything going. My pot is 100lbs+ and theres ussually 2-3 of us casting from it at a time. Proably about every 150- 300 bullets total. I believe fluxing keeps the bullets more consistant due to a more consistant alloy mix. I read someplace once of an old time bullet caster ( 1910-1920 or so) that had an agitator made for his pot that constantly stirred the alloy while he was casting to keep it blended. I have thought about this since even on my big pot a auger type agitator would have to turn very fast to keep the metal mixed and moving. a power screw driver would do fine. I recomend fluxing as needed and as often as you feel it needs to.

You should read Glenn Fryxl's articles. Once the alloy is mixed, it stays mixed.

[WFO2]

Thanks really new just second cast in the morning and wanted to know yall's thoughts . Its a 20 pound pot so I'm thinking that crud on top is normal and just go for it .

[bangerjim]

I NEVER put anything chunky in my bottom pour pots. EVER!!!!!! No matter what it is, it will eventually get down into the pour spout! Been there done that B4 I learned better.

Since I ( and hopefully YOU) have made perfectly clean and fluxed 3X feed ingots, there is absolutly NO need to flux in a casting pot. Only REDUCE the Sn back in.

To do that, I use a pea-sized piece of beeswax ONLY everytime I add new feed ingots to the pot. The surface stays mirror shiny and the beeswax keeps it that way. Parafin wax is a no-no in my process because it creates dangerous flare-ups that can cause burns. And it stinks to high heaven, unlike beeswax that smellss sweet!


The beeswax leaves a bit of black ash on top that I skim off to leave shiny surfaces.

That is how I do it.......with great success. Use whatever (you think) works for you.

[Shiloh]

Been using cedar shavings lately. Stir real well and leave it float on the top.

SHiloh

[DerekP Houston]

I don't flux at all when casting boolits. All my ingots are cleaned and fluxed prior to getting to that point. Once melted I skim what little dross/oxide is left on the top off and start casting. When I get around to remelting a large batch of ingots I'll dump all the dross I've been saving back in there to reclaim what tin is left over.


Thanks really new just second cast in the morning and wanted to know yall's thoughts . Its a 20 pound pot so I'm thinking that crud on top is normal and just go for it .

just skim the crud off the top and save it in a coffee tin.

[PaulG67]

I do not put anything in my casting pot but clean lead. All fluxing is done while smelting.