[SWO]

Someone gave me a can of misc. scrap lead. I melted it down in small batches to pour in my lead ingot mold. I don't have a large lead pot, so I used my electric melter that holds about 2 lbs. Most of the ingots are normal, but 3 of them crumbled like a block of chalk. Any idea of what material this was? It looked like lead and melted in about the same amount of time, but was a little whiter in color than the other lead ingots that I made.

[dlaery]

Question: What’s a SWAG?
Answer: SWAG is an highly technical, time-honored acronym for scientific wild-assed guess, a variant of WAG (a plain or unscientific “wild-assed guess”). It is a term to describe an on-the-fly appeal to intuitive processes that lie outside of standardly accepted scientific methodology. In other words, its a plain, ordinary “hunch.”

This is just a WAG, I would guess the lead was not hot enough when you poured it in an ingot and/or remove from ingot mold too soon.

If it was Zinc mixed with lead it would look like a slurry on top.

I don't know of any other metals that would melt like lead and be crumbly when poured in an ingot.

[JSC]

Another "WAG"

Did you flux the melt ?????

I have had some thing like this before ... mostly with wheel weights ... try a good fluxing ..

My

JSC

[hawnjigs]

SWO, are you saying the cooled solidified ingots were crumbly or when you remelted them to pour?

[SWO]

Originally Posted by hawnjigs

SWO, are you saying the cooled solidified ingots were crumbly or when you remelted them to pour?

They crumbled after I removed them from the ingot mold after a remelt. They were still hot, so I used a pair of pliers to move them and pieces broke off. I did drop a piece of wax in while the lead was melting to flux it.

I remelts them again last night and let them get a bit hotter than what I probably did the night before. This time, they held together and didn't crumble. I didn't realize lead had those properties.

[hawnjigs]

OK, I've worked with old wheel weight and battery lead scrap which hot ingots crumbled when grabbed with pliers too. I learned that hardening metal antimony causes a lead alloy to form a grainy structure that in sufficient quantity weakens intermetallic cohesion(aka crumbly) especially when hot. The more antimony present in an alloy the more powdery the surface appearance & the higher pitched the "clink" when dropped gently on concrete. I keep high antimony alloys separate from softer when melting into ingots, since they are best used for larger castings only. I would caution that wheel weight melting temperature should be kept as low as possible to avoid melt contamination with the occasional zinc weight which will melt at 787*F.