Bottom Pour

[686]

when you are bottom pouring how often do you flux? is it by how much new ingots you add or by time? thanks

[GabbyM]

Only when I add metal. After fluxing the surface will skim over with tin oxide then stabalize.
I use a 40 pound pot so it takes a while to draw it down. I don't add spur back while I'm casting.

[Shuz]

I flux when I add new ingots or sprues from the boolits I just cast. I also have found that floating new kitty litter added on the top of a melt will keep the alloy from oxidizing, therefore reducing the need to flux and stir more often.

[monadnock#5]

I've recently taken to mixing range lead with my wheelweights at a ratio of 1:2. I weigh the ingredients on a scale, and then melt the ingots in a stainless steel pot on a hot plate. It's just amazing how much more junk I'm able to flux out of the mixture. Junk that never gets a chance to foul the Mag 20.

So my current system is: render and flux in my cast iron pot; alloy and flux in my stainless pot; flux the Mag 20 only after the addition of ingots and sprues. Also, be sure to set a schedule for emptying and cleaning your bottom pour. Works for me. YMMV.

[docone31]

I have found, since it is a bottom pour, I add ingots when I get 1/3 down, and flux when I feel like it.
I also, scrape the bottom of the pot and where ever I can with a long flat blade screwdriver.
You would be amazed at how much stuff accumulates in the corners of the bottom, and sides.
I believe, the oxidation clumps, by their nature, prevent flux from releaseing them.
Since none of my ingots are perfect, I do pick up little bits of crud throughout the mix.
I ingot aside from my bottom pour pot. I do toss the cut offs directly back into the melt when I am casting. I just got into the rythym years ago.

[Le Loup Solitaire]

I always flux, stir and skim whenever/after I add new metal or when the melt starts to get "clingy" or starts to look and act "stringy". For fluxing material I usually use a slice of ordinary candle wax and light the resulting smoke with a match. I've also used Marvelux which doesn't smoke or smell as much. Bullet lube also works, but it is an expensive way to go. There are lots of other homebrew concoctions that also work. An important thing to remember is that when you flux and stir; try to go deep into the pot with whatever you are using to stir, as this gets slag, crud and dross to exit/float out of the mix where it can be skimed off. The pot should periodically be thoroughly emptied and cleaned. LLS

[686]

i guess i am some where in doing what some of you are doing. i have had a part in over 1,000,000 bullets hand casted. most by me, some by school kids yrs ago. the older i get the more i want to know. it is easy to see how bad i use to do it.
i am bottom pouring with a magma 90 lb pot. i do not fill it any closer than 1 in. from the top. this way if i forget and stick in another 6 lb. ingot it does not run over. i have done this with a rcbs 20 lb pot. makes a mess of your pants, a little warm too.
i start by fluxing when i make my ww, range lead, and soft lead ingots . when i put my mixture together for my bullet alow i flux. this blend has ww, range lead, soft lead, liontype, and 60/40 soder. i do all this mixing in about 150 lb pot. as i am adding and pouring my 6 lb ingots , i do not empty the pot. i also use a 60 lb pot at the asme time. i do a lots of cross mixing. these are my mullet alow ingots ready for casting bullets.
when i turn on my pot to cast and it is all melted and filled to 1 in, of the top i flux. if i get it to full the flux can run over the top as i stir. my ladel is a old lyman that looks square and makes it easy to scrope the sides and bottom. i scrape every time i flux.
as i am casting i normaly flux 2-3 times in an hr. i do add ingots to the pot as needed. i try to keep the level close to the same. some times i forget and have to add 2 ingots. i just put them in maybe 2-3 min. apart.
i also will let the pot go down about enugh for 2 ingots, but will add spru cut offs. i have always thought that what ever that needed fluxing that you could see on top would not bother the lead comming out the bottom.
HOW OFTEN TO FLUX is realy my consern. is there a reason i should flux more often or less often as i am casting?
this is very long but i like any help from others i can get and maybe the way i have been doing it might help others. it is not that i have not casted or fluxed, it is i am looking for others thoughts. thanks charles

[DLCTEX]

If you're getting good boolits, don't worry about it. If you see inclusions it's time to clean the melt no matter when you fluxed last. Some batches clean up easily, then some take a lot of fluxing and stirring to get the trash out. I think it's because some contaminates are harder to separate than others, or maybe the moon phase isn't right. DALE

[Calamity Jake]

WOW what happened to this trick from the old shooters sight? KITTY LITTER!!!

Thats right kitty litter, the cheapest pure clay litter you can find, you do not want any additives in it. And it is not a good idea to recycle from the litter box.

So after your finished fluxing your bottom pour pot add about 1/4 inch of kitty litter on top, it does many things, 1. it stops oxidation, 2 it acts as an insulater keeping the heat in. 3 you can sturr it into the alloy to flux if needed. 4 when time to add ingots, just lay them on top of the litter they will melt and self flux as it goes thru.

I leave it in the pot until it starts turning to dust(10-12 casting sessions) then skim it off, flux good and add new litter. Been doing this for 5-6 years now and I like it a lot.

I'm Calamity Jake, and I approved this message.