What caused this??

[taco650]

I smelted some lead SOWW's today and after fluxing with sawdust I got a blue color on top of my lead.

[Mitch]

Nice pure lead or dern close to it turns blue when you get it a bit to hot.no big thing it will be just fine. I would think if you have a hardness tester in is 6bhn or less.

[Dollar Bill]

That's lead oxide from over-temp. As Mitch said, no worries. It happens when mixing large batches. Just flux thoroughly before casting and keep the temp down.

[taco650]

I wondered if it was caused by a heat issue. I used a propane camp burner for the first time to smelt this batch. Heat control is just a knob on the side. I'll get it eventually LOL!

Thanks for the advice.

[Mitch]

I have found you realy don't have to get pure lead all that overheated to get the blue oxidation.i kinda like seeing it then I know what is in the pot.

[taco650]

I did a couple batches of COWW'so after these & they blued a little but not as much. I had also lowered the temp some.

[RogerDat]

Sometimes a pot of pure will have a freaking rainbow of colors on the top. Really a very pretty way for the universe to tell me to quit wasting propane and turn the burner down a bit.

[tmag97]

Pretty swirling blue colors is what I get melting sheet lead

[OS OK]

Just a note on temp…the other day I did a batch, piled in my 'cupcake' size ingots in the Lee 4-20 and just for giggles thought I'd set it to 4 1/2 or so, not quite 5 on the dial just to see how long it would take to melt and be ready. I did this because I end up at that setting roughly anyway trying with thermometer to run at around 725 degrees.
To my surprise it melted way before I thought it would…almost as fast I thought. I saved myself the frustration of going way over temp. and then chasing it back down and seeing blue in the pot.
No blue this time though…'just a note'...

OS OK

[Geezer in NH]

I love pure lead !!!!!