The tin can lead casting.

I've seen quite a few Seeker videos. Such an ambitious project. Somewhat less finicky than an America's Cup build, however.
 
Speaking of lead, yesterday we watched a program about walking the Harriot Way in the Yorkshire Dales, UK. I was surprised to see the importance and the extent of lead mining in the Yorkshire Dales. At one point, this region was the world's largest producer of lead.

I did some searching on line and found this article. https://www.mylearning.org/stories/lead-mining-in-the-yorkshire-dales/45? It is a complete and well written article of the industry there.
 
We were watching that show a couple weeks ago. There is also Time Team episode about Romans and the lead mines in Wales. Most Time Team episodes are available on YouTube as this one is.
Pierre
 
This one is about the lead mines in Herculaneum, MO. It's a horror film by today's standards. Even today, that town enjoys low 3rd grade literacy rates. Must be something in the water, eh?

 
graham-xrf said:
The melting of 2.1kG of lead in discard sacrificial half of a lube spray can in a woodburner turned out OK, though with lots of good experience.
That means lots of "don't ever do it that again" all the way to discovering how to deal with shrink voids in the top surface.
Originally from thread --> "Melting Lead Shenanigans", this is what happened.

View attachment 438325

Lead melts at only 327C (621°F), so putting the can among the wood coals in a living room woodburner was total overkill. Wood coals glow red hot, so are 700C to maybe 800C. Even so, it worked. Upon cooling, there was this big hole in the top surface. At first, I had no idea why.

Fill the hole
I went for a re-melt, this time done lots more conveniently using a regular plumber's butane/propane torch. I mean one of those atop a disposable hand-held fuel cannister. I stood the can on a piece of old fireplace insulation board, and just heated from the side. This time I could more easily stir (with borrowed screwdriver). Some yellow yuk slag and some bits of black stuff came to the top, so I dragged it to the side with a teaspoon, and scooped it out. I kept stirring, but very little more slag came out.

View attachment 438326

Then I got it that as the lower part cools, it shrinks from the outside. The fix was to let it cool, but keep re-melting from the top to keep the void filled. This, I guess, only happens when the top is wide open, and would not occur in a proper mold with sprues and vents. Clearly the cooled cylinder had shrunk lots more than the can, but it still would not just "drop out". I tore off the can in by twisting it around pliers "sardine can opener" style. It turned out better than I expected.

Upside down view.
A perfect replica of the shape of the bottom of the spray can. :)
Now we begin exploring what it takes to machine lead. I may need to give it a temporary aluminium disc screwed, glued, or somehow fixed onto one end, to have something that won't just go squish in chuck jaws. There is the need to bore a hole right through it. Drill press? Lathe? Whatever it takes to fit a support mandrel up it, so that one can have the other end held by a tailstock centre

View attachment 438327

I think the slag drag teaspoon looks well enough to get a wash and be returned to the kitchen before any confessions become necessary!
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Hoping that you’re joking about return the spoon to the kitchen. It will always be contaminated.

Dry pine sawdust makes an outstanding flux. It has to be from solid wood; not plywood. Plywood contains glue. That’s how I flux lead for bullets. They’re very demanding of clean, well fluxed lead.
 
David2011 said:
Hoping that you’re joking about return the spoon to the kitchen. It will always be contaminated.

Dry pine sawdust makes an outstanding flux. It has to be from solid wood; not plywood. Plywood contains glue. That’s how I flux lead for bullets. They’re very demanding of clean, well fluxed lead.
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Unfortunately - no joke! The things we do in ignorance!
As it happens, it was a stainless spoon, and nothing appeared to "stick" to it. Regardless, it got shined up with Scotchbrite, wiped over with IPA, and put back.

This thread is great - very educational about melting lead. I would not wish to divert the theme, but to catch you up from the original thread, I now await the results of recent diagnostic blood tests. The painful symptoms may be related to lead leaching from bone.
 
I used beeswax for flux when I was into lead soldiers in the 1980s.
Pierre
 
I had no idea that both pine saw dust and beeswax would be flux for lead.
I also had no idea someone would use a spoon that was used in the kitchen.. @graham-xrf I do hope you are ok.. I never cross back to the kitchen... if I use it in the shop it stays there.
 
woodchucker said:
I had no idea that both pine saw dust and beeswax would be flux for lead.
I also had no idea someone would use a spoon that was used in the kitchen.. @graham-xrf I do hope you are ok.. I never cross back to the kitchen... if I use it in the shop it stays there.
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Well.. unfortunately I am not OK, though I highly doubt that the spoon mishap has been the cause.
None of the spoon surface could have carried any lead significant back on its surface, given that it was so abraded when polishing it up. That said, my present condition has modified my life, not in a good way, and all onset in a short time. Yes, the symptoms all do match various forms of lead poisoning associated with low level long term exposure, but they also match various other ailments. Diagnosis is pending in a week or so.

Compared to what so many of the members in this forum do, inhaling fumes from red-hot chips reacting with oils and coolants, welding away without the 3M filter, hands in degreaser, casting bullets, spraying WD40 all over the place, my behavior seems almost angelic. That is, except for that one incident involving me mistaking the plastic orange juice bottle for one I had filled with methanol-denatured IPA, related elsewhere on this site. So yes, I do have a (poisoning) track record, but I do try to be aware. I wear the nitrile gloves, and do all the stuff involving protection, right down to the ear defenders. Its just that, sometimes it can go wrong!
 
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