"Fluxing" questions

[Ian]

I do basically all of the above, and often use a cedar stick to stir with. If you aren't stupid with it you don't get junk trapped in the melt, and nothing cleans the sides of a pot like a softwood stick, it's like a "magic eraser" for dross Klingons. So I basically dump a handful of sappy pine sawdust on top of the pot, swish the oxide scum through it, set it on fire, ladle metal up through it and pour over the top, and when the flames start to burn out I stir the hell out of it to create a vortex that cycles metal through the pot. Then I skim and take a few minutes to check the forums, size brass, pet the cat, kiss my wife, go pee, (not necessarily all at once) and come back and skim the rest, oxides and all. Then it's go time with the bottom pour.

 

[Mike W1]

Just a bit off the topic here, but as another suggested I made a scraper for my Lee 10# out of an old hacksaw blade. Ground off the teeth, contoured the end a bit to fit the pot and put a wooden handle on it. It's a lot easier to scrape the sides and bottom of the pot with it than with something wider.

 

[Ian]

Hmm. All the hacksaw blades I have already have a smooth side and rounded end.

 

[Longone]

I have read this and other posts and am still missing something. I use an RCBS bottom pour and I still get a restriction in the nozzle, I'm doing something wrong just can't put my finger on it.

I too started out using the Marvel flux stuff, seemed to coral the debris OK but it sizzled and left the pot a mess. Tried corn cob media and was much better but as I read it does leave some of it suspended in the lead and that would plug the nozzle. Went to saw dust, maybe I wasn't using enough or my stir timing was too soon or too late but it also seemed to leave suspended particles in the lead that would eventually end up in the nozzle or in/on a bullet.

I do normally run the pot down and then reintroduce the sprue to remelt, am I causing another issue by allowing them to cool and making the cleaning process worse?

I do most of my casting @ 750* read from a thermometer (RCBS), I mainly cast for handgun at this point with some 30 and 7mm.

Any help would be appreciated, but please................type slow.

Longone

 

[Rick]

Sawdust cannot get into the melt or under the surface in any way UNLESS you force it down under the surface, if you do even though the ash is far lighter than lead and you would think it floats to the surface much of it will not. Lead is dense enough to hold it in suspension. The correct way to flux is to use a ladle to bring alloy up to the surface and gently pour it through the flux. Do this long to get most all of the alloy poured through. Correct and proper fluxing isn't quick stir and done, it takes some time but the rewards are well worth it. Also I never use any type of wood stick to stir or scrape the sides/bottom, the stick will char in the melt and scraping with it will break off pieces.
.

 

[Mike W1]

It appears to me that any "fluxing" is best done in the initial process of turning whatever lead you have into ingots. When it's clean pour the ingots! Far as when casting the ONLY thing that goes into my pot is beeswax and that's not a flux as I understand things now. Maybe every 2nd or 3rd potful gets a smalll lump of beeswax and that's it. Pot stays clean and spout is open, after all you're only putting already cleaned ingots in there.

 

[Ian]

It appears to me that any "fluxing" is best done in the initial process of turning whatever lead you have into ingots. When it's clean pour the ingots! Far as when casting the ONLY thing that goes into my pot is beeswax and that's not a flux as I understand things now. Maybe every 2nd or 3rd potful gets a smalll lump of beeswax and that's it. Pot stays clean and spout is open, after all you're only putting already cleaned ingots in there.

Yep. Use clean ingots and only reduce oxides with wax or something like that as they form during the casting process and when you add back sprues, culls, fresh ingots, etc.

Personally, I use sawdust even in my casting pot but am careful with it. I keep hearing about people having spout clogs but have never, once ever had it happen to me.

 

[62chevy]

I use saw dust in my pot too but just move it around and never put it in or under the lead. I ladle cast with a Lee dipper, have a Lyman but don't like it, for casting and when making ingots to pour the lead through the wood chips. Never had a problem with crud in any bullets.

 

[Longone]

So reading between the lines, it would appear that when melting initially that would be best done in a larger dia. pan with a shallow lead content so as you stir the undesirable ingredients will float much quicker and easier. In the past that's the way I did it just because of the equipment I had, this last time I melted the weather didn't look like it was going to cooperate so I just melted and poured ingots.
I finished before the rain but now am left with a bigger headache. Does this sound feesable?

Longone

 

[RicinYakima]

If you don't mind spending the time, try polishing the inside of your cast iron crucible used for the first cleaning. That keep a lot of stuff from sticking to the sides. FWIW, Ric

 

[Chris]

Ric, good idea. Guys that go to stainless steel comment on how it's easier to make clean alloy.