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View Full Version : Sheet lead/flashing is a PITA.



JeffinNZ
05-13-2012, 08:48 PM
Team

I was given about 60lb of sheet lead a while back. I'll never say no to free lead but sheet lead is a PITA to smelt. The very thin material has a brilliant coating of lead oxide all over that acts as a fantastic insulator. Getting things started took a while but once up and running it wasn't too bad. A lot of work however compared to smelting WWs.

PanaDP
05-13-2012, 08:55 PM
Really? I love the stuff. I shoot mainly soft alloys for BP so I need those soft lead supplies.

runfiverun
05-14-2012, 12:36 AM
if it's the white coating i really hate that stuff.
it's hard as heck [over 35 bhn airc] and probably the most dangerous form of lead there is.
i'll wet it down and wire brush it off before melting.
the brushing helps it melt quicker,and then a super correct fluxing to get the oxides back into the melt.

geargnasher
05-14-2012, 03:29 AM
I pile it all in the smelting pot, cover it with diesel fuel, light the burner and set fire to the whole mess. The smokey, sooty flame reduces the heavy oxides as the pieces melt and crumble into the pot. The tar doesn't ever seem to really burn, but I got a piece with pine pitch sealant on it once and I thought I was going to lose the whole smelting setup, it burned like a metal fire and made the iron pot glow deep red. Any time I smelt stuff like that the respirator is on my face and charged with fresh heavy-metal-vapor cartridges.

Gear

Defcon-One
05-14-2012, 10:14 AM
Lead pipe is exactly the same. Heavy grey oxide and a ton of crud inside, especially in the drain traps. It is hard to get the heat to the metal because of the oxide coating and the odd curvy shapes.

But hey, it is all pretty Pure Lead ingots an hour later and I forget the mess pretty quickly!

sqlbullet
05-14-2012, 10:40 AM
You also have to keep in mind the higher melting point of pure lead compared to WW alloy, as well as the properties related to it's phase change. With WW you feel like you are getting somewhere starting at about 470° as it starts to slump. Pure lead has no slump temp. Solid right up to 627°, and then it just sits at that temp until it absorbs the energy of transformation.

Makes it seem like forever.

onesonek
05-14-2012, 10:50 AM
Lead pipe is exactly the same. Heavy grey oxide and a ton of crud inside, especially in the drain traps. It is hard to get the heat to the metal because of the oxide coating and the odd curvy shapes.

But hey, it is all pretty Pure Lead ingots an hour later and I forget the mess pretty quickly!

I have a bunch of pipe here that needs smelting,,,,,,,,
I hadn't thought about the heat issue with it.
Would it be better to leave an inch or so from the last for better heat transfer???
Just a curious thought,

Defcon-One
05-14-2012, 12:47 PM
If the last batch was pure lead, then YES! I am certain that you'll get a faster overall melt that way.

40Super
05-14-2012, 07:46 PM
Yep I just did 400lbs of lead pipe and its a pain to get through the oxide outside. I cut it into 4-6inch lenths and preheated on a hotplate while working with the pot. As the pot got lower I could add a lenthg or two and they would melt a lot faster.It helped to swirl them in the molten lead. I now have about 600lbs of 1/4plate to melt, but that doesn't have much oxides so it melts real nice.

docone31
05-14-2012, 09:11 PM
I just spray it with PAM! and then walk away for a bit.
All gone.
Comes out nice.

TCLouis
05-14-2012, 09:12 PM
When I think smelting, I envision a I am building a Funeral Pyre, light it off and walk off for an hour or so, then cast up about 400 lbs of ingots before the day is out.
Not likely an activity that can be accomplished in suburbia.

Several coffee cans of sawdust in the pot usually results in a layer of carbon on the surface of the melt and little oxide