De-Galvanizing metal ?

[jeep4x4greg]

any good way to de-galvanize metal?

a guy at work found the PERFECT tank in a junk yard to turn into a gas forge.

problem is, its an old RV water tank and its galvanized


i know the precautions to take when welding on it...

but will pose a problem during operation?

I plan to line it with about 3 inches of koawool.



let me know your thoughts.


thanks!

[rusty_iron]

Gday Greg,

Acid. A friends father ran a galvanizing plant. They used hydrochloric acid (pool acid) to strip gal off things. The solution thats left can apparently be used as a flux for soldering. He didn't say how strong to mix it, sorry.

I have used phosphoric acid (the acid in rust converter & coke) to remove gal, it works but not that fast, I probably should have mixed it stronger.

I imagine you can use any acid, including vinegar, it will just take longer.

An option would be to take it to a galvanizing plant and ask them to put it through the acid bath to strip it.

Be careful. Perhaps put it on an open fire after you have striped it with acid, to remove anything left. Stay well away from the smoke/fumes, they WILL KILL YOU!!!!

Regards
Rusty_iron,
Brisbane, Oz.

[Mills]

3 inches of blanket won't let the shell get hot enough to burn the zinc. Around the openings it will though. I think that I would fire it outside and let it go til it quit smoking, then sand back a bit more where it did burn off and go with that.

[Thomas Dean]

Call me "skeerd" or overly protective but I can't see the cost savings here. There are PLENTY of other things to make a gas forge from. The cost of the acid + time to 'acid clean' + despose of acid correctly...Then the water tank may have an enamel liner that you will have to deal with...
Just my $.02 worth....

[ThomasPowers]

Ifn I was wanting to do this I think I would build a nice bonfire around it and let it clean off the Gal that way. Stay away while it's working. The zinc oxide will not be that toxic in the ashes and I'd rather dispose of them than an acid mix----I wouldn't do that much soldering in the rest of my life!

[pete46]

DITTO WHAT THOMAS SAID!
KEEP FUEL ON TOP TO BURN OFF EXTRA FUMES!
THROW FUEL ON AFTER FIRE BURNS DOWN A LITTLE!
WOOD TYPE FUEL TREE BRANCHES BOARDS ect....
p.s. i know u r not an idiot ,but b carefull!!!!

[Rich Hale]

If someone in your area inhales the smoke and especially if they have some previous lung damage you may be liable for damages. As said above not worth it get a good tank or build one...then no worry...

[RegionalChaos]

I'd think a perfect tank wouldn't be galvanized?

[ThomasPowers]

Rich; I assume you don't use coal for the same reasons. I know a smith that coal smoke sets off his asthma.

Yes this is a bit problemical in city or surburbia; but out in the country I can shoot at folk that get close enough to breath in the smoke. (As tresspassers I am allowed to fire warning shots!)

[Hoary]

I guess this is along the lines of the topic, but I was wondering, I've seen some forges using metal tubs or buckets, I think I could pick one up from a hardware store, but are they normally galvanized? Just wondering...