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bbs70
02-14-2009, 09:20 PM
I need some help with something I've never run into before.

My set up.
Two weeks ago I started using a turkey fryer and a dutch oven.
I use 3 Lyman aluminum ingot molds.
I smelt my lead, flux it, and skim off the dross.
I then turn the burner down enough to keep the lead hot, but not too hot.
I fill the molds, when I finish pouring the third one full the first mold is ready to be dumped then poured again, then the second, so on and so on till my pot is almost empty.
As I said after I pour the 3rd mold the first one is ready to dump with no problem.

NOW, here is the question.
Two days ago I acquired a partial bucket of what the dealer said was solder.
It was mostly wadded up solid solder wire like you would use with a soldering iron.
I put it all into the empty dutch oven and melted it.
As usual I poured all 3 molds then dumped the first one to start over again.
When I dumped the first mold the ingots fell out and made a mushy pile on my work bench.
I waited a couple more minutes before I dumped the second mold, the ingots came out and were still somewhat soft yet.
I left the third mold for 5 minutes more and dumped it out , but they still seemed a little soft to me.
I filed all 3 molds again and waited 5 minutes before dumping, but they still seemed soft.
I'm at a loss as to why.

I've never had this trouble with wheel weights or pure lead.
Can someone explain?

runfiverun
02-14-2009, 09:44 PM
tin melts at 450* and solidifies at this lower temp too.

KYCaster
02-14-2009, 09:44 PM
The solder has a lower melting temp than your Pb and WW, so has to get colder to solidify. Just takes longer cause it has to lose more heat.

Jerry

bbs70
02-14-2009, 09:55 PM
Didn't know about the 450*, that would make sense then.
I guess then that I have a bunch of high tin stuff here.:drinks:
It sure had me scratching my head.

Thank you gentlemen, I appreciate the information.

Tom Herman
02-15-2009, 01:22 AM
The solder does have a much lower melting temp than lead or wheel weights do. So, if you have a hot alloy, it will need to cool muc lower before you can release it from the molds.
Solder is a GOOD source of Tin for flowability of alloys... Shoot for 1-2% Tin for best results.
Congrats on your score!

Happy Shootin'! -Tom



The solder has a lower melting temp than your Pb and WW, so has to get colder to solidify. Just takes longer cause it has to lose more heat.

Jerry