Zinc fumes?

M

Mark Redmon

Joined
Nov 7, 2007
Messages
451
So I've been toying around with the idea of trying to make some mokume, but I haven't really found much on what people do to reduce the risk of zinc poisoning. I'll probably try a 3 color brass, NS and copper billet. Seeing how the brass and NS have a decent amount of zinc, I'd like to survive my first experiment. I can't recall how many times I've read warnings about galvanized steel since I joined the forum, so this prompts the question: What do you guys do in order to not poison yourselves?
 
Three things here.

First, most nickel silver that is used for jewelry and knife work is low in zinc. The grade of brass many like in mokume' is cartridge brass, which is 30% zinc.

Second, the way mokume' is made, there should be little or no fumes to deal with. It is usually make in a closed foil pouch or in a closed and oxygen shielded oven.

Third,zinc poisoning is not what you get from the fumes in making mokume', or when hot working with brass or galvanized metals., Breathing these fumes causes metal fume fever, ,often called metal fume sickness, which makes you feel ill, but is not severe or fatal. Zinc poisoning is caused by absorbing too much zinc internally through medicines and other products, and is fairly hard for humans to get. It is not caused by exposure to or breathing fumes. It is a serious problem for pet dogs and birds.


Reading a good book on mokume' should give you all the procedural info you need.I recommend, " Mokume' Gane - A Comprehensive Study, by Steve Midgett.

Stacy
 
Most brass also contains lead. It is a machining aid. I don't know what you do if you breath too much lead fumes (hang out in the political forum I guess), but the treatment for zinc fumes is to drink milk (don't ask me why).

I think it would be easy to accidently get these metals hot enough to fume (900 F for lead). So I would do it in a well ventilated area with a cross breeze and minimize my exposure.
 
I believe zinc fume fever is a genuine phenomenon that is best avoided. Folks who weld galvanized metals sometimes complain of it. Minimizing fumes and adequate ventilation are highly recommended. A draft hood like setup to vent out fumes would be great (even if zinc isn't involved). Here's a link to a discussion on the subject, http://www.iforgeiron.com/forum/f35/galvanized-zinc-fumes-milk-8498/. Perhaps one of the most infamous cases of zinc poisoning is the tragic death of Jim "Paw Paw" Wilson, http://www.anvilfire.com/iForge/tutor/safety3/index.htm. His event was an extreme one though, and he had pre-existing compromised respiratory issues.

I don't believe the mokume fusion process should generate much in the way of toxic fumes though, as you are not heating the metals to smelting temperatures, just fusion temps. Never-the-less, precautions are always prudent endeavors though.
 
If you're scrounging brass , brass plumbing fixtures are usually made from leaded brass as is almost any brass being machined .It isn't good for forging as in mokume anyway.
 
Stacy, Thanks for the clarification. I also appreciate the recommendation. I've been looking for a starting point, and that book sounds like a good one! I may order his video as well.

Phil, Those links should be required reading. I may have to put some fans near the forge or pull it outside to keep fume concentrations low.

Nathan and Mete, the brass I have is c260 (cartridge brass) and should be 70/30 Cu/Zn

Thanks guys!
-Mark
 
I have made a significant amout of the type of mokume you describe and one good thing is that you are in little danger if you do things properly. The zinc from the brass will not dissociate in large amounts below the melting temp of brass. To make mokume you want to get close to that temp, but not past it. So, if you make properly fused mokume you should not be in any danger. However if you melt a billet, you should take more caution.
Del
 
I have welded galvanized metal twice in the three years at my current employer and both times I did it neer an open door AND I wore a respirator under my welding hood. it might not be that bad but I don't like to take chances. So be careful when working with it hot.
 
Red brass, which is used for plumbing pipe, contains no lead. I'm thinking it is 230 or 260, but I don't recall.
 
Yes, Jim's death was sad, but the great overexposure, smoke and particulate inhalation, and severe pneumonia is what killed him....not metal fume fever.
Stacy
 
It seems to me that everything we work with; steel, micarta, G-10, carbon fiber, lead, all kinds of wood, has it's health hazards.

"Do you want to live forever?"

When you get old like me then you worry about it less. I still worry but it's not like I will live forever anyway.

Take precautions and enjoy the results of your labor. That's what I always say, sometimes.

I've been loading lead bullets for years. I've been casting lead bullets for years. What, me worry? Nah.
 
I've had metal fume fever from zinc once. It was not fun. I would suggest good ventilation, a properly rated and fitted welding fume respirator, and if you end up making a lot of mokume, maybe a good fume extractor/filter unit
 
bladsmth said:
Yes, Jim's death was sad, but the great overexposure, smoke and particulate inhalation, and severe pneumonia is what killed him....not metal fume fever.
Stacy
Click to expand...

There was a picture of "Paw Paw" posted just a couple days before he burned off the stack of galv. pipe. He had a very bluish (cyanosis) tint to his face showing he was not getting good O2 perfusion. At that stage any respiratory irritant was going to be dangerous.

Back when I worked in EMS we transported a 15 y/o girl that was sprayed by a skunk at close range. She was asthmatic and went into cardiac arrest but survived.

So is skunk musk deadly? For her, with a pre-existing condition, yes. To most others it is not.

With all the homespun forge designs being used out there I would rather see the saftey focus on CO poisoning and silicosis from the insulwool. Those are equal oppurtunity health hazards that do not require a pre-existing condition.
 
Del, I appreciate you chiming in on this. My interest in working w/ mokume stated largely after seeing your work in jewelry. I hope to work up the skills necessary to start working in precious metals.

As Dave mentioned, we do work with some nasty stuff.. I guess my initial post was merely trying to ascertain: How nasty? I always try to work as safely as possible. While I'm hardly a model of good health or clean living, I don't see any need to further exacerbate the situation. I'll be sure to have the shop well ventilated and maybe have a fan or two running by the forge. I may have a chance to play a little over the weekend after doing a little more reading on the subject. Thanks again for everyones input... this forum truly is a wealth of knowledge.
 
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