Water and casting lead?

[davinci]

It's a long held belief that getting even a drop of water in a pot of molten lead will cause a tremendous explosion from the quickly boiling water.

I'm an experienced welder and spent a little time in college as a foundry apprentice and did quite a bit of casting aluminum, so I like to think I have a little knowledge on this subject, but I'm not an expert.

Foundry sand contains an oil, and a percentage of moisture. When using foundry sand that is too dry (or been used too many times), you add some annealing oil to make it bind because it doesn't dry up. I've heard of using water as a binder for foundry sand, but all the moisture that is left in a mold will leave 'dimples' on any part of the casting as the air has no way to escape. This is true of aluminum, I have never casted lead into a sand mold.

I started casting for the season the other day. It was a mostly cloudy day, no forecast for rain. set up the pot outside, started casting, then sprinkles and of course rain. I unplugged my pot and ran inside just before the rain started coming down hard, and I'm sure that the pot was still molten. I thought I was going to have to scrape lead off my bricks for months, then I looked out the window and saw nothing at all like what I was expecting. Rain was falling into the pot, on everything else... no explosion.

Granted this was rain, not like I poured a bucket of water into my pot somehow. The only evidence was little craters in the top of the now-hardened lead.

I got into a discusssion on another thread about this where mention was made of "the lead must have cooled off very quickly" or "unless water gets under the surface of the lead you won't get an explosion"

does anyone have any experience, or know anyone, who has ever actually 'exploded' a pot of lead from putting in a wet ingot or wheel weight...or somehow putting water into the pot intentionally. Please, no "my brother's friend's cousin-in-law told me" experiences.

Thanks!

 

[ReloaderFred]

The problem lies in getting moisture submerged into the molten lead, where it quickly forms steam, which must escape. I did this inadvertantly many years ago and had lead splatters all over the place. There wasn't an explosion, per se, but there was a fairly violent eruption of escaping steam, even though the amount of moisture was quite small. I wear an apron, gloves and eye protection when casting, and my apron and gloves had plenty of splatters on them, as well as the surrounding area.

I stir my molten lead with a long handled spoon, and if I don't lay the spoon on top of the melt for a few minutes to dry it completely, I'll get bubbling of the molten lead when I put the spoon into it cold. There is a lot of humidity in the air where I live, so just about anything exposed to the air has moisture on it.

As for the event you describe, the moisture (rain drops) was falling on the surface of the molten lead, so it was forming steam before it was able to enter the lead. Steam on the surface won't cause anything but rising mist. If those same rain drops had somehow gotten below the surface before being converted to steam, then you would have had lead splattering, caused by the steam trying to get out at a rapid pace.

Hope this helps.

Fred

 

[bfox]

Hi
I said in the other thread I did .
Not an explosion but kind of a pop and it threw some lead out ,
not all but some .
I was putting in a 1 lb. ingot that I guess had some condensation on it .
I got a few minor burns from it but luckily nothing bad .
Not something I want to do again .
If you want to mess with 700 degree lead and water go ahead .
But I know for sure I am going to be more careful .

Bill

 

[rcmodel]

I started bullet casting in 1961, and have been doing it ever since.

And I'm the one who started this discussion in the other thread you mentioned.
I said "water in the pot will result in a trip to the emergency room!"

Perhaps I should have said "may result", instead of "will result"?

I still believe that is very sound advice to those new to bullet casting.
And there are a lot of those folks on this forum!

And yes, I have had a small lead explosion more then once, when dropping range scrap jacketed bullets into a pot.

I assume the water or moisture was inside the bullets, between the jacket & core.
As soon as I dropped a handful in the pot and started stirring them in, I got splatted pretty good!

I also witnessed a larger, and far more serious one in the 5th. Army AMTU shop in 1967. That one was from a folded section of scrap lead plumbing pipe dropped into a large gas-fired alloying pot.
It blew lead all over the place, and severely burned the guy working the pot.

Now, (unless bullets have been in the scrap bucket for some length of time to dry out), I heat all range scrap up with a propane torch now before I throw them in the pot, to make sure there will not be another steam bubble explosion.

Regardless, many folks use a bucket of water on the floor under the pot to drop hot bullets into.
In that case, culled imperfect bullets may end up with a drop of water in a void, or hollow-point cavity, and go back in the pot right away.
That's going to result in an accident!
Don't do it!

Instead, throw them in a scrap bucket and let them dry out for a few weeks. Use them in another casting session after they have had time to dry out completely!


rcmodel

 

[scrat]

true true true.

water in the pot wont cause an explosion but a pop where some lead can fly out. i have casted a long time. i can recall an occasion where i was sorting through some bullets that i had just casted. there were a few that did not looked too good. i threw one in the pot and POP and a little gurgle. some lead did splatter. not a lot. just a little. it was enough though to make sure that i dry off all bad bullets and make sure they are dry before putting them back in the pot.

 

[Sharps Shooter]

It’s probably been 30 years, but I remember once when I finished a casting session I still had 4 or 5 pounds of molten lead in the pot so I poured it into my ingot mold pan and set the pan out on the driveway to cool. Then I forgot about it for a few days. It might have rained or snowed before I started another casting session - I don’t remember. What I do remember is when I placed one of those 1-lb ingots that had been outside in the driveway into a fresh pot of molten lead.
However, it wasn’t a “tremendous” explosion by any means. It was just kind of a “poof” and a few tablespoons of molten lead spewed out of the pot. My arms would have gotten some burns except for the fact I was wearing heavy leather gauntlet gloves that went halfway up to my elbows.
Another example of molten metal and water was when I worked in an elemental phosphorous plant where they had 4 massive electric furnaces to melt the ore. Every so often they had to run a “tap” on those furnaces, meaning they had to drain off the slag and molten metals. The metal tap holes were lower on the furnace’s sidewalls because the metal was heavier and settled to the bottoms of the furnaces. When the furnace tappers did a slag tap, they ran the molten slag straight out into the “slag pit” where water was sprayed on it to cool it. But metal taps were run into huge sand pits inside the furnace building. Once the metal cooled, it was called a “chill” and they hauled the chills out with a crane. But way back when, before the EPA and OSHA got so powerful, we used to talk the furnace tappers into allowing a little bit of a metal tap to escape to the slag pit. They’d only do it at night when the big bosses weren’t around. It was spectacular! Chunks of red-hot slag and metal as big as cantaloupes would get blown clear over the top of the furnace building, and that was about 90 feet tall. It probably wasn’t the smartest thing we ever did, but that’s how I learned about molten metal and water.

 

[Walkalong]

I backed rcmodel up in the last thread and stand by it. I have seen it with my own eyes and talked with others who have as well. We caught flak about it. I guess some folks just need to see it with their own eyes to believe it.

It can be anywhere from a "little pop" to a spectacular emptying of the entire lead pot. It depends on how much water and how deep it gets in the pot.

 

[zxcvbob]

When I have scrap lead to melt down, I fill a Revereware saucepan with dirty lead and don't care if it's wet or not. It will dry as it heats. I don't add any more to the pot once it melts, and I don't stir until the whole contents are smoking hot. That way, no water can get in.

When I'm casting bullets, hot sprues and hot reject bullets go back in the lead pot right away (some people say you shouldn't even do this.) Reject quenched bullets don't go back in the lead pot until after I'm all finished and the pot has been turned off long enough that the lead is hardened.

 

[Vern Humphrey]

It doesn't take much of a pop to seriously burn someone -- especially someone not wearing proper protection.

Years ago, I had a friend who washed some scrap lead to get all the crud off it. Among the pieces he washed was a hollow lead soldier. When that sucker went into the pot, he received serious burns!

 

[Paul "Fitz" Jones]

As a hobby and commercial Police reloader I operated 50 lb to 6,000 pound lead pots. When starting I would over fill them with solids of scrap, Police range bullets and tire weights. As the pots melted from the bottom and the solids dropped I could add more scrap on top of solids still in the pots as any moisture would evaporate before the chunks or scrap lead reached the liquid lead and melted.

However I have been burnt by having a 50 pound pot full and was filling ingot molds with my ladle but a drop of sweat dropped from my nose so I turned as fast as I could but got splattered with droplets of lead ruining a pair of polyester pants and had small burns on my arm and neck.

From then on I wore a face shield, denim cap backwards an apron and denim clothing that I could peel the lead off of without damaging the material as a seagull dropped a load once when I was properly dressed. After that living near the ocean I always used my 50 pound pot on the patio under it's roof.

 

[spencerhut]

When I was a kid . . .

I was stupid enough to melt some lead on the stove in a little metal measuring cup. Don't remember exactly what I did, but water was involved and the little measuring cup of molten lead exploded like a bomb all over the kitchen. Lucky I didn't put an eye out.

Now ask me about the time I mixed Draino, aluminum and water. That was a trip to the ED. Those little Draino crystals keep burning after they embed in your face, forehead and eyeballs.

 

[darwin-t]

If you put a wet ingot in the lead, the lead will immediately "explode" out of the pot. I used to work in a file factory, in the hardening dept. The operators used tongs to put files in the lead (the floated and there was a bracket that they hooked the tang under). Then they took them out of the lead and put them in water (salt water, I think). anyhow, if they get distracted and put a wet file in the lead, ALL of the lead came out of the pot and knocked them back against the wall, covered in hot lead. It never happened while I worked in that department, but there were a lot of very jumpy people working in there.

When I worked in a foundry, they had large gas powered flames keeping the ladle dry. If the molten magenese hit the cool damp concrete floor, it was very unpleasant for everyone in the vicinity.

 

[jmorris]

zxcvbob Uses the technique I now use, if you start out cold any moisture is gone way before the lead will melt. A printer friend once gave me a few hundred pounds of linotype, some must have had moisture and when added to the mix, some of the erupting lead made it 16’ to the roof of the building. Maybe I should make always where safety glasses my signature, they saved my a$$ that day (one lens had a spot on it the size of a quarter). Oh, also a hat and old welding jacket….

 

[Jim Watson]

as a seagull dropped a load once

I read of a case where a Junebug flew into a lead pot. Fatal for the bug, painful to the caster.

 

[ReloaderFred]

My wife always said Junebugs were evil............... Now I know she was right.

 

[dmftoy1]

I don't know about a tremendous explosion but I've added a slightly damp wheel weight to a smelting pot and had a result very simliar to what happens when you drop some frozen food into a fry daddy. Popping, sizzling, etc. with little lead "drops" flying out of the pot . .and if it hits your skin it does hurt a bit.

FWIW.

 

[yammerschooner]

Here is the result of a damp, not super wet, wheel weight.

 

[rcmodel]

Yep!
That looks about right!
BTDT!

When water turns to steam, it expands 1/1,600.

Or:
One gallon of water becomes 1,600 gallons of steam!

Or
One "drop" of water becomes 1,600 "drops" of steam!

The water to steam reaction has a higher expansion ratio by volume,then gasoline, black powder, smokeless powder, and many blasting agents.


rcmodel

 

[Walkalong]

BTW: When water turns to steam, it expands 1/1,600.

Thanks rcmodel. I never did find that, only how quickly it happens.

When boilers blow up it is usually from them going dry, the safeties not working (shutting off the burner) and, when the tubes are red hot, water being dumped into the boiler. Now THAT is impressive. Thankfully, I have never seen it in person. (I took care of 6 boilers for several years at the hospital) I have seen pictures and it will blow boilers out through block walls.

 

[griz]

Just in case you still don't think it's worth worrying about, here is a picture of my safety glasses after it happened to me. They looked worse than that when it happened. It was about five years ago and a lot of the little specks have fallen off. I keep them as a reminder of how painful stupidity can be. The biggest injury was a second degree burn on my wrist where the gloves and long sleeve shirt did not cover. I also had small spots of first degree burns on my face.

The area looked just like Yammer's pic. It was also louder than I expected.

 

[bfox]

Griz
Did you do that when you put an ingot in ?
I got a cheap plastic face shield after it happened to me .

Bill

 

[griz]

Yep, a big chunk left outside and apparently damp from dew. I was melting big pieces (30-50 pounds) to clean them up and cast them into one pound ingots. Was trying to ease that chunk in slowly to avoid splash and it slipped out of my grasp. If I owned an automatic kicking machine I would have stood in front of it while I was shaking my head.

 

[Upriver]

One more vote for care when dealing with melted lead - I've had spatters (pops, whatever) from adding "damp" lead when casting fishing jigs. It was a lot like adding water to bacon grease on the stove. The first (and last, so far) time this happened to me, I had been working for over an hour with no problems, and must have picked up a piece of lead that condensation had formed on without noticing it (working outside, in the evening).

Always wear gloves, long sleeves, and eye protection.

 

[Gewehr98]

Yammerschooner, thanks for the picture!

I made the mistake of putting a recently-quenched cast boolit back into the hot Lyman 10lb pot several years ago. How I avoided serious injury is beyond me, because there was molten boolit alloy everywhere! While I wish folks like DaVinci would see such spectacular reactions to answer their incredulous-sounding questions, I wouldn't wish the potential for severe burns on anybody.

 

[Vern Humphrey]

While I wish folks like ****** would see such spectacular reactions to answer their incredulous-sounding questions, I wouldn't wish the potential for severe burns on anybody.

As Will Rogers used to say, "There's three kinds of people. There's those who can learn from books. There's those who can learn from others. And there's those who have to pee on the electric fence for themselves."