TIG Welding Zinc

I believe the fumes from zinc are highly toxic. Why would you want to burn it?

They are toxic if you burn it. If you melt it, however, it is weldable.

I have had limited success. Initially, my wood substrate was smoking out after about three inches of weld and reaking havoc. still having difficulty with consistancy.

second question.... zinc countertops and vent hoods are becoming big business. i dont like the material personally. too soft.

Reference your question #2: I don't see a question

Zinc metal as kitchen counter? My memory is a little fuzzy, but will that not react to copper pots and pans? How about contamination of foods?

I know you are not really looking for a critique, but are you really using elemental Zinc? Not alloyed with something?

no, no question, i guess. just looking for someone that has done this to commiserate with and maybe learn something.

the copper probably would react if you left it in close contact for long enough. it would add to the patina which in rich ladys' kitchen would be a plus. food contamination is iffy. the tops that i have done go out with the understanding that it is not a food contact surface, though yes it is the kitchen counter. so far they have all agreed to use a cutting board when filleting the fish.

no, not elemental zinc but 99%. dont remember the alloying agents.

is there a section on here for welding, machining and fab work?

Have you tried brazing? Or, are you stuck on TIG?

http://wiki.answers.com/Q/How_do_you_do_zinc_welding

I have brazed it with jewelers torch. the sheet is typically .060".

brazing it is messy/sticky/oily with the flux required and makes it difficult to grind and finish.

I think it is coming down to more precise amp control and very short welds.

they will be beautiful fuses or welds for an inch or so and then go to hades after much more than that. yes, using base material sheared for filler, when used.

I think that the tolerable temp range is much narrower than i am used to with other metals and am getting it too hot with built up heat. that's my current assumption.

hard to say, i dont have any metalurgical training, just experience and some modicum of common sense.

still looking for someone who has experimented with this...

I would think a forum at a place like http://www.millerwelds.com/ might be a better place to look... i just did a keyword search "zinc weld" http://www.millerwelds.com/search/?q=WELD%20ZINC

you might find someone with first hand knowledge to commiserate with!

sounds like a tricky material.

Johnny B

thanks, Johnnyb.

This has been a two year saga. I have been throwing this out there when I find like minded discussion, of which this site is definitely one!

Hello, I have tig welded much zinc galvanized steel. for a butt weld it is best to grind a little bevel to expose the steel as the zinc will smoke and cook off. Then we covered the weld with some aluminum paint.

Hey rusty. this is straight zinc sheet. no steel involved. thanks though!

Without ignoring the safety factors involved with arc welding zinc, my guess is that the metal requires less power input as the weld progresses because the substrate is getting hot. One common method of dealing with this is to use a conductive metal backing plate to conduct excess heat from the weld joint. Sometimes backing plates are liquid cooled.

Good stuff welderman! That is exactly right. the substrate is holding the heat and I am pretty sure that is where my problem is. Typically, the application is either countertop or kitchen hood. the tops are by nature wood substrate which of course smokes out pretty quickly destroying the weld if you dont stop before the smoke penetrates the argon envelope. We have cut the wood back and set in another layer of zinc to sheild but i think the shield might need to be copper or steel to sink the heat out underneath. i have tried the back plates but can only get that on the outside.

When I used the word substrate, I was referring to the zinc sheet, not the wood underneath. You haven't revealed details of the joint geometry. I'm assuming it is sheet to sheet butt and flat. I suggest you relieve the underlying wood and heat sink the zinc sheet by any means available. Copper would work well as long as it doesn't alloy with the molten zinc. I imagine a thin copper heat pipe would be about as good as you could do. Don't let the wood under the zinc get too hot. The vapors will affect the weld.

Google HTS2000.It is a low temp hi strength brazing alloy for all white metals.It can be applied with butane or oxycetelyne torch.

Good luck,

HTRN

Wow! That hts2000 is expensive. I used to see the infomercials on that stuff.

You're right welderman, I neglected to mention the wood originally, it doesnt happen in all situations. I havent figured out how to eliminate the wood but we have taken to relieving it back a ways and lining with additional zinc underneath. I think the copper will be better in the long run.

What do you mean by 'heat pipe'? I'm guessing that a pipe in contact with air flowing through it?

Copper also makes nice counter tops. I don't want to get into a lengthy description of heat pipes. You can Google it. A heat pipe is a two phase passive heat conductor that uses a working fluid and a wick. Its important property is that it can conduct large amounts of heat with a very low temperature drop. They have much lower thermal resistance than a hunk of copper. In your situation, you would vaporize the fluid at the welding end. The vapor would rapidly travel to the condenser end where it would condense back to liquid. A wick helps to transport the fluid back to the heated end. It's like a pump-less refrigeration system. However, I suggest you start with a copper backing plate and determine whether the situation improves.

Thanks welderman.

I'll let you know what happens.

There was a filler wire on the market years ago that was made by Linde Division of Union Carbide. It was called Number 19 Cupro. We made hoods for welding boothes using this rod and TIG (GTAW) in electrode negative with pure Helium gas. We left the high frequency on continuous. The amperage was down to about 7 to 10 amps. The Tungsten was 3/32" diameter and was alloyed with Zirconium. We also had an air fed helmet.

This has been 40+ years ago so the rod is probably not even available anymore.

Alright, here we go..

We were just talking about it and are currently thinking that the temp range where the material becomes molten is very close to the temperature at which the material smokes out, (narrow heat range between molten and burning) thereby destroying the weld. I want to say that our tungsten is lanthanated and 3/32 in dia.. tough keeping a stable arc down that low too. running at different times, miller 250 and miller A/B/P 330. In some instances, there is some impatience induced by the need to receive that check! i.e. lack of cool down between maybe 1-1 1/2" of weld length, skipped around.

thoughts?

Also, running a/c, hf on continuous, straight argon.

Dont know that i have done anything elec negative with high freq on cont.

I can lay a beautiful butt weld in pure zinc on A/C, regular thoriated tungsten. Treat it like brass, dont push the weld, pull it when you feed filler. However, I cannot get the metal to weld on a corner or tack with just the base metal. I cant figure it out yet, but Im sure someday I will.

Hey guest,

I have found the same. lets chat if you have time.

shea 205-966-0825 or shea@stolisma.com

Just read a year or so of your discussion on welding zink. I have been working a similar problem. If you are still working this problem or want to discuss leave a post. It is an interesting problem of which I have had little success but I can confirm nearly all of your observations.