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stubert
07-03-2010, 08:01 PM
I got a bunch of lead from my father in laws garage after he passed a few years ago. I was mixing up an alloy today and threw in a roll of sheet lead to lower the bhn. I was keeping the mix at about 600 degree's. the sheet did not melt until I upped the temp to 650. It looks like lead, I can scratch it with my fingernail and it is really soft and bends real eaisy. Possibly Tin?

lwknight
07-03-2010, 08:36 PM
Maybe your thermoneter is a bit off. Also old oxidised lead has a kind of insulation on it so its harder to melt.
Crank it up to about 700 degrees.

mooman76
07-03-2010, 09:15 PM
Tin actually melts at a lower temp than lead. Pure lead takes a bit more than 600. More like 650, I don't remember the exact temp.

docone31
07-03-2010, 09:30 PM
Sheet lead is going to take some heat. Also, as stated oxidation will take some heat.
When melting silver a ball of metal will form inside the ball that is melted. That is oxidation. Same with lead. Lead however takes less temp.
Here is where you wait a bit. Put in the lead, turn up the heat, and it will melt.

sagacious
07-03-2010, 10:59 PM
No mystery. What you saw is normal, and indicates that your sheet is pure lead or very nearly so. Pure lead melts at about 620*F, so you'll need to set your temp at about 650*F to melt it.

stubert
07-04-2010, 08:11 AM
Thanks, The sheet lead makes sense. I was alloying down a bunch of lasercasts that were way to hard. Started at 22-23 bhn, now i've got a pot full of 15 bhn. (as checked with a Lee )