think zink

[brino308]

Ok so I started casting to make shooting more economical and then found myself buying more and more stuff to the point that shooting has become secondary to the hobby of casting. Now I find trouble shooting my process has become an obsession. It was one of those afternoons where the melt was the right temp and the mold was the right temp and everything was right with the world, when suddenly I looked at my sprue pile and saw what looked like broken concrete. Could I have gotten some zink in my alloy?
Please Help
Thanks171580

[osteodoc08]

Melt and mold too hot and cut before completely cooled is what it looks like to me.

what did the alloy look like before and while heating up/melting?

[gwpercle]

What is your alloy composed of and how were you fluxing and with what ? May not be zinc .
Welcome to the addiction ,
Gary

[Yodogsandman]

Looks normal to me. Just dropped too hot. The granular surface is the antimony as it was forming molecular chains, dropped before it was fully cooled.

Welcome to your new addiction!

[brino308]

My alloy is battery clamps (free from work )and lead free solder . Using the pencil method my bhn is about 12. I flux with bees wax

[brino308]

Thanks for the replies, I knew I came to the right place

[Cowboy_Dan]

What you are seeing is called frosting. This is caused, in your case, by a hot sprue plate. If you got zinked then you would have seen "metal oatmeal" on top of the melt.

[bangerjim]

Don't worry about Zn if less than 5%. Just add a bit more Sn to decrease the surfact tension when casting. And you boolits may be a bit lighter. No big whoop.

Been there......done that.......no problems.

You have a simple heat problem.

Cast away!

banger

[scottfire1957]

You're good.