Comment by jpdoctor

My grandfather worked for AC Gilbert, which made the Erector Set, and American Flyer trains. I had rather complete sets growing up, and couldn't figure out why my erector set and toy trains were so much better than everyone else's.

But another toy was a lead casting kit: You would melt lead in a crucible, which would then pour into a mold. http://www.girdersandgears.com/kaster.html

Never had the atomic energy kit, probably because I was already too stupid from the lead fumes out of the crucible.