I was casting some boolits today and I had something happen that made me just dump the pot (into ingots) and stop.
I had already cast about 10lb and my alloy is 5:1 COWW to linotype and my casting temp is around 675.
I added in another ~10 lb with the same ratio and after I fluxed it in I started seeing some strange results.
On every cast the boolits were very frosty and the sprue just crumbled when opening the plate. The lead in the pot looked fine. It was shiny and consistent so I went and cast a few rounds and all the boolits came out the same. So, I thought that I might have some sort of contamination so I thought I have enough boolits, I'll just get this stuff out of the pot and ask the folks at Cast Boolits if it looks as if I got some zinc in there or maybe just too hard of an alloy?
In this pic, on the left is an ingot of my COWW lead then next to it an ingot of some 4:1 COWW to lino from a while back (oxidized a little) and then the next two are what I just dumped out of my pot. They are much whiter and not smooth/shiny.
Is this Zinc contamination or is it that maybe the COWW lead I got was much harder than I thought?