Do you empty your casting pot?

[kccraft]

I've been reading up a bit about casting since I'm interested in getting into it. I have read that you should always leave some lead in the base of the pot when you are done casting. It makes sense that it'd re-melt better with good surface contact, but how critical is it to do that?

In trying to imagine my ideal process, I'd like to cast ingots of pure lead (I have access to quite a bit of raw lead at the moment) and mark them as such. Then I'd like to melt down wheel weights into ingots and mark those. Then when I'm working up an allow for a particular purpose I'd be able to accurately judge the ratio of pure lead to WW.

But if you have to leave lead in the base, then every time I switch alloys I'll be tainting it with that leftover.

Is there a process for cleaning out the pot between alloys, or would I have to get a different pot for each if I really wanted to keep them "pure?"

[muddy]

Full or empty it doesn't really matter. I cast all my center fire bullets out of WW with nothing mixed in. When done I fill the pot before I shut it off so next time all I have to do is fire it up. I use a 10 pound Lee pot for my pure lead to cast muzzy stuff and I leave that full to. If you are mixing alloys all the time you will probably want to empty the pot after each session so just drain the pot into an ingot mold, mark the ingot so you remember what mix it is and then just start over next time.Once you drain most of the lead out of a bottom pour pot there isn't much left in the bottom, a couple scrapes of a spoon will remove most of the left over slag and a quick wide with a wad of paper towel will finish it off.

I think you will find that straight WW will cast good bullets and adding to much pure lead will just make your bullets too soft for center fire stuff. When you want to turn pure lead into something other then muzzy fodder I think you will find you will be better off adding other know material to it then WW. There are a ton of recipes on the net to turn pure into Lyman #2 or other mixes that cast great bullets, most of these recipes are made from adding solder, antimony, pewter and tin to the lead in some fashion or the other.

[dewittdj]

If the pot is subject to oxidation on the outside and inside when it is empty, then, IMHO, leaving some lead in the pot will protect the base metal of the pot from oxidation, similar to tinning an iron. You always leave the tip of an iron tinned afterwards and tin it before starting a new job. I figure the same would probably hold true for the pot. A hot surface will attract and react with oxidants in the air much faster without the "protective" lead coating in place. Heat transfer much more effectively with clean (nonoxidized) surfaces making contact.

[FrankenHollow]

I usually flush.

[kccraft]

I like the idea of using a dutch oven or similar for casting ingots or making alloys, and use only ingots in my pot.

I don't have any sort of outdoor/camping stove that I could use for that, so hopefully I'll be able to find one cheap. If it turns out to be cheaper to buy a second lee pot as a dedicated alloying/smelting pot and keep the main pot free of the contaminates, does that do just as well as the dutch oven method?

[FrankenHollow]

[James]

Near as I can tell, It does not really matter. Leave it however you get done with it. I have done it all ways, and seems that when you heat the pot up again, whatever you put in it will melt. The oxidation is not a problem. Flux and skim and you are good to go.

[Rhino]

I read on numerous forms about how it is good to leave at least a little lead in the bottom each time. It was related to helping the spout remain clean and not getting slag and dirt into it that builds up on the top of the melted lead. Not sure if that is right, but that is what I have been doing. I try to keep the pot at least 3/4 full while casting and then when I finish I have been pouring ingots to take the level down to an inch or so. I may skip the ingot part and just leave the remaining lead like mentioned above.

[James]

"Is there a process for cleaning out the pot between alloys, or would I have to get a different pot for each if I really wanted to keep them "pure?""

If wanting to change alloys when the pot is hot and lead melted, I would just pour the lead out into a mold. Picking up a small pot with a pair of pliers to pour is pretty simple. However if using a dutch oven it will be a little harder. Be careful. Maybe dip most of the lead out before pouring?

If you leave a bit in the pot and cool it, the lead will come right out when the pot is cool It does not stick to the pot.

[James]

If the pot is subject to oxidation on the outside and inside when it is empty, then, IMHO, leaving some lead in the pot will protect the base metal of the pot from oxidation, similar to tinning an iron. You always leave the tip of an iron tinned afterwards and tin it before starting a new job.

Interesting thing about the cast iron pots, you can't tin them on a bet. They seem to repel the lead. If lead is left to cool in the pot, when the pot and lead is cool, just turn the pot upside down to empty it. The lead falls out as it does not grab onto the pot at all. If you pour all the lead out of a pot it all goes out, none is left on the surface of the pot. IOW no tinned surface remains.

In the dry climate I reside in my pots never rust just sitting around as long as they are indoors and don't get actual water, as from rain, on them. Let them get wet and see how quickly they rust. I don't know how they would do in areas that have high humidity. In any event, when you melt lead in them, the oxidation comes off and can be skimmed off when you flux. I guess it won't hurt a thing to spray a protective cover of oil on your pot when in storage to keep the rust off. It would just act as flux and burn off when you heat it up again.