? Brown coating on casting pot

[franklin_m]

First time casting guy. What is this brownish coating on inside of my pot after I was done? Does it need to be cleaned out? If so, how?

(Cast was pure lead except for some (25) slightly oxidized lead balls that came with the gun)




Sent from my iPhone using Tapatalk

[mold maker]

I've been casting sinkers since 1960 and boolits since 64, but I've never seen anything like that brown/tan in my pot.
What did you use for flux? Did the alloy cast good (no wrinkles) round balls? Was the pot brand new with a coating to retard rust?
A picture may be worth a thousand words, but that one raises a thousand questions.

[Walter Laich]

1st: yes it does need to be cleaned off. Usually once it cools it will scrape off using a putty knife. I've also had luck while the pot was still hot but most time the ¢rap ends up back in the melt. DO NOT REUSE IT--trash it

where did you get your 'pure lead'? guess all the balls are gone into the melt, too.

There was something in one of those two sources. Pure lead won't look like that and oxidized lead shouldn't leave that reside either

[franklin_m]

It was a brand new pot. Cleaned with alcohol before using. No flux. Lead came from rotometals.


Sent from my iPhone using Tapatalk

[D Crockett]

simple and easy tool to make is a hack saw blade with about 1.5 inches of the end heated red hot and bent into a 90 you then use the teeth side to scrape the crud off the pot. what it is no idea there and you can use this tool while the pot is full to get the crud to come to the top of the melt D Crockett

[franklin_m]

simple and easy tool to make is a hack saw blade with about 1.5 inches of the end heated red hot and bent into a 90 you then use the teeth side to scrape the crud off the pot. what it is no idea there and you can use this tool while the pot is full to get the crud to come to the top of the melt D Crockett

Thanks!


Sent from my iPhone using Tapatalk

[edctexas]

Still no suggestions as to what the crud is?? I have had once sometime ago and after I drained and cleaned the pot I have not seen it again. Just love to know what the crud is!

Ed C

[Walks]

I think it might be dirt. I got the same thing a couple of times when melting down 1 lb ingots I bought from a lady who found them buried in a junk pile behind a "new" house she had bought from an estate sale. I washed the rest of the ingots with a scrub brush & rubber gloves. Problem went away. I cleaned the inside of my pot with an old bait knife & steel wool. Then simple soap & water dried with paper towels.

They were "LYMAN" ingots that tested out at 11 bhn.

[JPinMI]

I don't know what it is but I get it quite often, and I consider my lead source clean. It has always been easy to clean though by chucking one of those wire brushes into my corded electric drill.

[Bent Ramrod]

It's one of the lead oxides, which go from a light yellow color through red to brown to black. Or a mixture of them.

Make sure you scrape around the sides and bottom of your pot when you flux. That will bring the loose stuff to the surface, where you can skim it off. More will form in the course of continued heating and casting, so you'll have to repeat the scraping when you flux again.

I never clean the pot back to bare metal, unless I have a bottom pour spout that is crudded up. I just scrape the loose stuff and expect more. It's inevitable. Any time you heat something up to melt it, a little bit is going to decompose, especially that part next to the hottest surface. My Chemistry professor told me that 50 years ago, and, except for maybe ice melting, everything else seems to follow the rule.

[lwknight]

Agree with Bent Ramrod. I get a thin layer is yellow dust on my pot mostly at the level that is working. It is not below the lowest that I get to before adding more and not above the high level. I never worry about it but just keep going.
Edit to add:
Pure lead will oxidize pretty fast so you will get that yellow build up a lot more than when using something with tin in it. It only takes a small percentage of tin to inhibit oxidation. When using something like #2 alloy or even hardball alloy you will probably not even see that oxide line.

[deac777]

It's lead oxide. If you decide to scrape it off, try not to breath in any of the dust. It is less dense than pure lead and can become airborne.