Melting lead shennanigans

[graham-xrf]

I used a Dutch oven (cheap one) to melt lead for kart racing weights.
Happy to not be doing that anymore.
John

I'm sorry, but that one went over my head.
I know I am prone to stumbling over minor cultural differences, but exactly what feature makes an oven "Dutch"?

 

[WobblyHand]

I'm sorry, but that one went over my head.
I know I am prone to stumbling over minor cultural differences, but exactly what feature makes an oven "Dutch"?

https://en.wikipedia.org/wiki/Dutch_oven It's a covered pot, typically made of cast iron, like this:

 

[benmychree]

Oh this brings back memories.
When I was around 12 years old too far away to admit to my mate and I used to go scrabbling accross the shed roofs removing the what we thought was lead squares (I believe later we found they were zinc) from under the nail heads holding the corrugated asbestos down.
These were melted down in a tobacco tin on a primus camping stove and cast into lead half crowns.
These lead half crowns were accepted in cigarette machines at that time the results of which were then sold in school at 2d each to all the idiots that wanted them. (I have never smoked and could never understand why anyone would want to)
This escapade lasted for about 3 months before the ciggy machines suddenly stopped accepting our counterfeit cash.
Oh happy days.

I love it!!

 

[682bear]

I've been casting bullets from wheel weights for 30- something years, mostly for .44 Magnum, .30 carbine, and 30.06... I've also probably made over a ton of lead shot for shotgun reloading.

No offense intended, but your setup makes me nervous... there is no way to control how hot the lead becomes. I've been taught that as long as the lead is silver, it is safe. If it starts taking a gold tint, it's time to lower the heat input. If it begins looking purple, it is about to start 'outgassing'... and you need to be wearing a respirator...

-Bear

 

[graham-xrf]

I've been casting bullets from wheel weights for 30- something years, mostly for .44 Magnum, .30 carbine, and 30.06... I've also probably made over a ton of lead shot for shotgun reloading.

No offense intended, but your setup makes me nervous... there is no way to control how hot the lead becomes. I've been taught that as long as the lead is silver, it is safe. If it starts taking a gold tint, it's time to lower the heat input. If it begins looking purple, it is about to start 'outgassing'... and you need to be wearing a respirator...

-Bear

None taken, and many thanks for the response.
I know that there is accumulated experience here that includes years of discovering stuff that is not such a good idea!

One of the reasons I put it in the woodburner is because I wanted it to be where it could not hurt me. I didn't fancy pouring anything, and just standing a can of lead in there seemed like a simple scheme that avoids much of the work and skills needed to do it any other way.

There is a temperature gauge indicator mounted on the cast iron body above the doors, with "most efficient" range marked 100C to 400C. Of course, there are wood coals in there glowing red, which is way more than 400C. The design is modern, arranged with two air inlet routes, one of which takes (very) hot air through the fire, up, and guided back to the front at the top, to descend across the quartz windows. That air is hot enough to turn any carbon smuts and deposits into CO2, and keeps the windows clear. All that is left is a very fine white ash which wipes off with a wet cloth.

I am OK with metal being outgassed of trapped air, which is a different thing to the toxic vaporizing metal off the top, which happens all the time once it is molten. The air that enters the woodburner for combustion can only end up going up the flue, and would take lead vapors with it, to become white lead oxide ash. As a sort of "smelter's fume cupboard", I am thinking it might be a whole lot safer than melting a batch on a welding table. While the lead was melting, I was not even there!

Estimating from the colour of the red, the temperature of the thin metal above the molten lead was about 700C (about 1292°F). The lead below was glowing very faintly red, I estimate about 580 to 600C, which is much hotter than needed. The "can" was, of course, completely unsuitable other than to simply let it cool in there. Once the lead was liquid, the can could not be gripped by anything without being a softer-than-usual, squishy, thin-walled can again, so there it stayed overnight.

 

[cathead]

Plumbing in olden days was done using cast iron pipes. The connections were made using lead and oakum so it was
common for plumbers to have a gasoline powered heater with a large pot made of cast iron and filled with lead. It's
obvious now that the plumbers were contaminating themselves by working with the stuff but the biological effects are
commonly not seen for years. Lead concentrates in the bones and the body has no way to remove it so not something
to be used casually. Overheating lead generates lead fumes that is more toxic than people realize. It's best to melt
the lead outside with just enough heat to get the job done. I found this photo on the internet.

I have one of these old heaters. It holds 2.5 gallons of gasoline and is capable of generating a lot of heat. I use it solely
for stuff like heating up the diesel tractor on a cold day. The tank has a pressure gauge on it and uses a small hand operated
air piston to pump it up. I generally pump it to twenty PSI which is plenty and the gauge goes well over that to eighty PSI
or so. It makes one think when pumping air pressure into a canister of gasoline! The amazing part is that it is probably
a hundred years old and still works well, more than I can say for most stuff made these days.

It would be a good idea to read up on the toxicities of lead before heating up a pot of it. If you do, you will be a lot
more careful with the handling of it. That's not to say that I might make another lead hammer or two but will be mindful in
doing so.

 

[graham-xrf]

It would be a good idea to read up on the toxicities of lead before heating up a pot of it. If you do, you will be a lot
more careful with the handling of it. That's not to say that I might make another lead hammer or two but will be mindful in
doing so.

Look along the periodic table around lead. See the other heavy, low melting point metals around it. Mercury exudes toxic vapors all the time. See Thallium, once used for rat poisons and insecticides, and historically popular as a murder weapon known as "inheritance powder". So nonselectively toxic, it is now banned.

In the same group as lead, but lighter, we have tin. This is as toxic or more so than lead! Then there is Bismuth, Antimony and Arsenic.

I get to the conclusion that pretty much all metals, except possibly gold, and platinum, are toxic, and the vapors are always dangerous. lead, of course, has that "cumulative" property.
----------------------------------------------------------
Regarding the hammer.
Do you mean one that will not mark surfaces, or do you mean the sort with the lead shot inside that does the "double blow" effect?
Is that what is meant by the name "dead blow" hammer?
I am intrigued by those.

 

[RJSakowski]

Here is a graph of lead vapor pressure vs. temperature.

In my experience, lead starts to discolor at slightly over the melt point due to air oxidation so color is not a good indicator of vapor pressure. I expect that we had higher exposure standing in ICE exhaust in the 1970's from the tetraethyl lead additive to gasoline.

In exposure to a direct flame, there will be some airborne lead oxide particles due to flame turbulence. In addition to heavy metals, most elements and compounds are toxic at some concentration. Heavy metals such as lead can be removed from the body. Calcium EDTA will chelate lead , allowing it to pass through urine. The treatment has been around for decades.

Dead blow hammers have lead shot contained internally. The shot deforms inelastically upon impact, reducing any rebound.

 

[graham-xrf]

For all this, I look at the cast cylinder on my desk (yes - weighing down paper right now), and I feel unsettled by stuff like in the video. When I was young, I often had my hands in aviation AVGAS. I would cheerfully solder circuit stuff. OK, I didn't eat it, but now I discover folk who use shooting ranges also wear masks!

 

[David2011]

I've been casting bullets from wheel weights for 30- something years, mostly for .44 Magnum, .30 carbine, and 30.06... I've also probably made over a ton of lead shot for shotgun reloading.

No offense intended, but your setup makes me nervous... there is no way to control how hot the lead becomes. I've been taught that as long as the lead is silver, it is safe. If it starts taking a gold tint, it's time to lower the heat input. If it begins looking purple, it is about to start 'outgassing'... and you need to be wearing a respirator...

-Bear

Old thread; I know. I’m a bullet caster as well. The gold to purple on the surface of molten lead is most likely oxides of tin. The longer it’s exposed to air the darker it gets, starting at golden and ending in dark purple. Lead vapors don’t develop until the mel temperature hits about 1140 degrees F. That takes a lot of effort.