is galv sheet metal safe to use?

[craigcraig]

is galv safe to use for an oven? i work at a fab shop and sometimes we get stuff in thats been galved and if we do any kind of filing,grinding,and welding on it we have to where mask cause of the toxins in galv. so i was wondering if you use galv sheet metal for the oven would the heat cause the galv to release fumes? any info would be helpful.

[m67bd70x]

I've had no problems yet. But you are correct, welding galv does produce fumes that can be hazardous to your health.

[edwardpic]

Our oven is all galvanized sheets of 20 gauge inside and outer skin...I did a burn off for an hour before I used it to cure parts...No problems so far and no release of fumes to make me sick.

Ed

[engineerscott]

Galvanized steel is coated with a layer of zinc. Zinc vapors are toxic to breath (as are the vapors of most heavy metals). This is why you will hear warnings against welding galvanized steel unless you remove the zinc coating (in addition to being toxic the zinc will contaminate your weld and weaken it).

Zinc turns from a solid to a liquid at 787.15 °F and from a liquid to a gas at 1665 °F. Since you are generally curing powder at around 400 °F you are probably o.k.. The only caveat I would say is that 400 °F is the average temperature of your oven. The heating element itself might be as hot as 2000 ~ 3000 °F (depending on how you are controling the element) and the metal near the element will definitely be hotter than 400 °F. I would let the oven heat up and run for a while in a well ventilated area and I wouldn't hang around too close for the first heating cycle.

If I had the choice between galvanized and ungalvanized sheet steel I would pick the ungalvanized. If all I had was the galvanized I'd probably use it with the caution noted above. No matter what you build your oven out of you need to use it in a well ventilated and avoid breathing any fumes it gives off.

Scott