Poor Ingot Poured

[Brucifer]

Hi all. This may be my first post not sur. I have been reading and am very thankful for all the information.
I just did my first melting of wheel weights. I use a LP furnace (plumber’s pot) and stick-ons sorted from the clip-ons. Tried to remove the zinc and steel from the lead. Don’t think I did a good job of that. The stick-on seemed to work well and I was able to keep the temp below 700 deg F. the zinc ones floated. Didn’t know there were zinc stick-on. My ingots poured well.
Now for the clip-on. I think the zinc melted with the lead. I tried to skim it off but not pleased with the ingots. I poured into a small cast iron pot. (8LB) when I knocked the ingot out the bottom was crystallized and broke off. Is this a temp problem or zinc problem?

[SciFiJim]

Looks like you dumped the ingot before it cooled sufficiently. When it is still hot it is soft enough to break. An 8 lb ingot like that is going to take a while to cool enough to stay together.

[Defcon-One]

Remelt, repour, then be patient. Give it 5 or 10 minutes to cool, then drop it into a bucket of water, or wait even longer. It will not break up.

Probably not Zinc but the temp when you dumped it out!

[Larry Gibson]

As mentioned you dumped the ingot to soon. Let it cool more. What you see in the crystalline structure is the antimony rich/tin poor nature of WWs. That causes the tin and lead to harden and different temps. Let it cool. If you want excellent bullets instead of good bullets add 2% tin to that alloy before casting bullets with it.

Larry Gibson

[Brucifer]

Thanks for the help and lesson. patients with a new project not one of my strong points. 2% tin will do,

[D Crockett]

Brucifer if you will pay the shipping I will send you as a Christmas gift 2 of my 2 cavity ingot molds but this being the giving time of the year just pay the shipping and they are your give me a pm and let me know if you want to do this D Crockett