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View Full Version : Smelting and casting dangers.... Need info



retyc
08-27-2010, 11:37 AM
Hey guys, new to the forum, so Hello from the Lone Star State.

I am looking for the definitive answer about smelting wheel weights and casting bullets. Is lead vapor actually produced below the boiling point? I have heard both sides of this story, and I am looking for some reference material that is not propaganda..... ie EPA ****.

Also, I have young kids at home. If lead vapor is produced at smelting temps, is there any particulate located in this vapor. In other words, is there a possibility of me dusting their toys or the yard with lead dust?

And no, I'm not a hippie. It's just the wife is looking for verification after seeing me melt all the junk off some wheel weights yesterday.

Thanks in advance

sargenv
08-27-2010, 12:05 PM
The vapor that is produced is all the junk coming off the ww's, usually the paint and other crud that floats to the top. I usually smelt with the lid on (just in case there is latent moisture or something in the pot to make the lead spatter). After I've had it on the burner for about 20 mins and mostly melted, I take the lid off and usually the exposure to the air ignites the fumes instantly, and only for a few seconds.. I then put my fluxing material in and sift out the crud and clips.. usually I flux 2 or 3 times. The lead will not vaporize as long as you keep the temp close to the melting point.. for me between 650 and 700 deg. Keeping it that low also doesn't allow any errant Zinc ww to melt and mess up the pot. After all that when I am satisfied my melt is clean, I ingot it and go to the next box of WW's starting the process all over again.

cobbmtmac
08-27-2010, 12:11 PM
retyc,

First welcome aboard. I have be casting and smelting for about 7 years, always with good ventilation. I do not have any scientific proof that it is not harmful. I can tell you that I have been involved with the Nevada Cast Boolit Shoot, (NCBS) all durning this time. Many of the NCBS casters have been casting and smelting for 40-50 years. Several of them have told me they have their lead levels tested every few years, with the results being normal.

Again not scientific, but its good enough for me.

mdi
08-27-2010, 12:32 PM
Keep the temps below 900 degrees, don't stand in the smoke, use common sense, and nuttin' will happen to you OR your kids. Vaporized lead and lead oxide are the "toxic" states of lead, and with a very little bit of care, you'll never encounter either. I don't wire brush the white stuff off old lead, nor max out my lead pot temp...

P.S. Lead isn't an evil entity just looking to jump on unsuspecting youngsters and poison their blood. It's just a natural occuring metal.

mold maker
08-27-2010, 01:22 PM
The major danger in smelting lead is the dross that floats on the melt. It contains all of the lead oxides present. Common sense says not to breath the smoke, and contain the dust from dipping off the dross. Keeping the area clean and properly disposing of the trash, is all that's required. I smelt over a large scrap of plywood to keep drips off the cement. They are unsightly, but harmless. If concerned wash the area down with a hard spray of water to get rid of residue.
The big lead poison scare comes from a time when almost every thing had lead paint on it. As it broke down it released lead as dust onto everything near by. We were literally raised in a lead atmosphere. Not saying lead is safe, but almost all of us lived, had families and survived. I have cast since 1958, at first with very primitive home made equipment. Knew nothing about ventilation, ate and smoked while casting. I never had levels tested until the last few years since retirement. I now handle lead almost daily and smelt or cast on a regular basis. My blood levels are below what is considered normal.
Keep your kids away from any lead activities because of the other dangers, and they will grow up amazed at what Dad does, especially when their old enough to shoot the ammo you make.

fredj338
08-27-2010, 05:16 PM
Interesting. http://www.engineeringtoolbox.com/melting-boiling-temperatures-d_392.html Does latent evaporation mean lead vapors? If so, just stay down around 700deg. You don;t want your zinc melkting anyway.

462
08-27-2010, 05:43 PM
Retuc,
Welcome,

Somewhere in the archives there is a similar thread. One of the members posted a link to some scientific/official type information. If memory serves, lead vapors do not occur until around 1200 degrees Farenheit. Don't worry about lead vapors.

As far as what's in the rendering smoke, it's nothing more than what's already in the air that we breath daily -- brake dust, and road dirt and grime.

For me, more of a concern with small children would not be the vapors but the hot, melted lead. Keep them more than a safe distance from your rendering/casting area and all will be okay. My wife and grandkids know to keep safe distance from me when I have the pot going.

colonelhogan44
08-27-2010, 08:01 PM
Latent heat of evaporation is how much energy is absorbed (in Kilojoules per kilogram of substance) in order to evaporate the substance. The 859 for lead is the amount of energy required, not a temperature. Technically, there is lead vapor produced, even at low temperature, but the vapor pressure of lead anywhere within normal casting temperatures is negligible. I calculated it out before i decided to start casting, and If memory serves it came out to something on the order of 0.3 PPM lead in the air directly above the pot at 750 F. Again, it's negligible.

Echo
08-28-2010, 12:34 AM
Welcome, retyc. The answers above get a big +1 from me. I am a noobie to some in this group (just been casting for 40+ years), so I am still learning.

Wear gloves while smelting and casting, and keep your hands out of your mouth. Wash your hands directly after taking the gloves off. It is my understanding that, generally speaking, the lead that gets into our system generally gets in through the mouth, and not through the nose. For that reason, I don't wear a respirator for either activity, but I do try to stay up-wind when smelting outdoors.

And another +1 for keeping young kids away from you while dealing with molten lead. To me, that is a far more dangerous factor than lead fumes/dust for kids - well, grown-ups, too. I doubt there is any among us that haven't got a few scars from lead splats. The SAS Time-Outs I often wear are nicely decorated, if one were to look closely, so it happens.

chris in va
08-28-2010, 12:36 AM
P.S. Lead isn't an evil entity just looking to jump on unsuspecting youngsters and poison their blood. It's just a natural occuring metal.

Careful with that logic though, so is mercury, cadmium and uranium...all very toxic.

NSP64
08-28-2010, 01:02 AM
retyc, lead is horrible and dangerous. Pack it all up and send it to me to dispose of properly.




Ps welcome to the addiction.:kidding:

KYCaster
08-28-2010, 01:15 AM
I agree with Colonel Hogan...look up the vapor pressure of lead and you'll find that at normal casting and smelting temps there is no danger of lead vapors.

I'm more concerned about the other stuff mixed with the WW...adhesives, lubricants, tobacco products, razor blades, half eaten McDonalds hamburgers....most of those things are more toxic than lead.

Keep your smelting operation away from your kids and the areas they play in. If you intend to have more kids, take every precaution to prevent inhaling ANY toxins.

If your kids are curious, use your casting session to teach them the proper use of safety equipment and the importance of personal hygiene...and teach by example. Learn where you're most likely to encounter lead contamination (de-priming and case cleaning) and limit your family's exposure to those operations.

Good luck convincing the wife.

Jerry

FISH4BUGS
08-28-2010, 02:58 PM
I shoot submachineguns with cast bullets. I smelt and cast a fair amount. The smelting is smoky so don't breathe that junk in. Stay upwind or use a respirator if you wish. Casting is very safe in my opinion.
The problems come when you smoke or eat while you smelt or cast. Lead dust, lead oxide, petroleum products and who knows what else is on your hands and also comes out of the smelt. Flux often and USE A THERMOMETER. Keep it under 650 and you won't have issues, especially with zinc ww's. Casting you can run as hot as you need to because lead does not vaporize until something like 1100. THAT is when you need to be concerned.
Wash your hands thoroughly when you do these things and NEVER smoke or eat while you are smelting or casting. THAT'S where lead gets into your system.
By the way, I do NOT use a respirator and wash my hands at every break in smelting or casting. I get lead levels tested every year in my annual physical. Lead is not an issue.

retyc
08-28-2010, 04:47 PM
Thanks for all the info Guys!. Fred, I should have known you'd be over here also.....

The problem with the internet is if you search for accurate lead info, you get a bunch of EPA "It'll kill you!!!! Don't touch it!!" BS. I explained to the wife it was safe, but she wants documentation. I think the lead vapor tables and some other info will work. Any way I can prove particulates don't exist below lead vaporization?

Also, the wife is very bright. She knows the smoke is from the gunk, but you know big plume of smoke coming off the pot right as she walks out the back door. Bad impression, so to speak.

As far as the kids, they don't come outside when I'm working with lead. At least not yet.

HeavyMetal
08-29-2010, 11:13 AM
Tell SWMBO that she might pick up a couple of the lead testing kits out on the market.

With one of these she can do some testing of her own and find out where and where not the lead is.

She might be surprised if your in an older home! Down side is you may get some extra chore's!

In reality your going to have more exposure from your brass cleaner, if you have one, than from casting and smelting provided, of course, that you take the common sense approch in handling and storage of the raw materials.

If you want to have her search the net for Tin Soldier molds and such. In the late 1890's through 1920's complete kits were sold to children to melt lead and cast there own tin soldiers to play with!

Very collectable today these toys were a given in every day life and considered no more dangerous then than an X Box is today!

finishman2000
08-29-2010, 11:54 AM
do it outside, problem solved

crabo
08-29-2010, 01:56 PM
[QUOTE=retyc;983381]
Also, the wife is very bright. She knows the smoke is from the gunk, but you know big plume of smoke coming off the pot right as she walks out the back door. Bad impression, so to speak.

I have a sheetmetal windbreak that goes around my turkey fryer to funnel the heat upward, but I use a big fan that is pointed above the smelting pot that keeps the nastiness moving away from me. Makes it a lot easier to have the smoke going away from the garage and where I sit on my stool and rest, as I work.

colonelhogan44
08-29-2010, 06:20 PM
http://www.powerstream.com/vapor-pressure.htm

Here's the chart I referenced. Some conversions and calcs are needed to get them into layman's terms that the wife can understand more easily (Unless she has some background in thermodynamics). If you don't know how to do them, I'll help you out.

retyc
08-31-2010, 07:55 PM
http://www.powerstream.com/vapor-pressure.htm

Here's the chart I referenced. Some conversions and calcs are needed to get them into layman's terms that the wife can understand more easily (Unless she has some background in thermodynamics). If you don't know how to do them, I'll help you out.

Colonel,
By all means, put it in layman's terms.....

MtGun44
08-31-2010, 11:38 PM
Theoretically lead vaporizes at all temperatures, it is in a dynamic equilibrium with the
environment. The question is "how much?" It doesn't suddenly vaporize at one set temp.

The important point is that the amount that vaporizes below about 900F is so small
as to be totally negligable. IIRC the vapor pressure is something like a thousandth of
a mm of mercury. 760 mm mercury = 14.7 psi, so you can see that the tendency to
lost an atom into vapor is not zero but not far off, either. REALLY - don't worry about
breathing lead vapors. Worry about eating it on your hands, food, cigarettes, drinks,
etc. This is the real world hazard.

Of course, at room temp my guess is that the one or two atoms per year lost are pretty
much OK, health-wise.

Bill

colonelhogan44
09-01-2010, 01:37 AM
I'll post in detail when I have a little block of free time to grind it out.