American Welding Society Forum
Been doing some stuff for a new client off and on at a new installation. Thier client is super picky to the point of being anal about small small things (they expect perfection on everything). Anyway they have some hot dip galvanize cat walks and a small tear in a kick panel was found. It had to be repaired under one of two conditions: remove the entire 25ft catwalk repair it and re-dip it. or repair on site and "hot stick" galvanize it. I had never heard of this "hot stick" and nobody I spoke with at the welding supply etc. had any idea. Anyway the end customer was so picky they had to come watch it being done...great since it was my first try doing it!!!
Well there is such a thing and it is pretty easy to do. It also is way better then zinc paint, probably the next best thing to hot dip. So all I am saying is this is out there if you did not know about it. I got my stuff here:http://www.rotometals.com/product-p/galvanizingrepairstickrecalv.htm
Here is a video of it being done: http://www.youtube.com/watch?v=l_gLN-4rEHk
It works well and is pretty easy.....getting the temp in the right range makes it go much better.
Glad I bought two pounds...I got to go back out there and add some rails.
I'm not sure anyone would re-dip anything galvanized, I've ask that question before and no one ever wanted to do it. the zinc sticks have been used for as long as I been in the business, over 33 years now.
ctacker They may have required a shot blast and re dip or just out and out replace which probably would be cheaper. I got my info second-third hand, never got to see the contract...from all the work I have done out there it was a doozy of a contract.
I have seen All-State Galvover rods in an Airco catalog from the '90s, but never had any or tried to use them. Good to hear such a thing works.
It is far as I am concerned a high temp solder Dave...it flows and acts like solder, not like silver solder but plain ole solder at its melting temp. If you play with the torch just right you can get it on pretty thick. Cool stuff...been welding all my life and did not know of such.
Its definately a handy little tool to keep in the tool box, but i will warn you under 90% of the situations play real freaking dumb about its existence or you will be doing way more of that than you ever wanted and chewing into profits rapidly.
I have been to the galvanizers enough to know that in order to re-dip a part that is already HDG, they will have to strip the entire piece first of any galv that's on there and then re-dip the entire piece. The new galv won't stick to the old.
It's the acid bath that etches the steel to make the galv adhere. Yes some places use blasting to prep the material to get it to stick, but an acid bath is still required to clean the part of contaminants.
The video was interesting how they used a wire brush to spread it around. I would think the wire brush would leave lines and areas for it to rust and streak but the theory is good. I would still spray a coating of ZRC over it to be sure.
Like Eekpod said, HDG materials cannot be re-dipped unless it is sent through an acid bath first, which removes all of the old zinc. This doubles the cost.
Also, the worst case of zinc poisoning I've ever had was from galva-bar coating handrail welds.
The stuff works good, if you don't get it too hot, but be careful because it can either kill you or make you wish you were dead.
I HATE galvanize. It has made me so sick too many times cutting and welding galvanize. Now I don't even get close to galvanize with out a respirator on.
I built some handrails with post and rails out of 1.5 inch tube. They had stock panels, already galvanized, welded between the rails and post. I don't know what the galvanizer did but I don't remember them charging more for the panels already galvanized. It all came out fine. I thought they dipped everything in the acid vat as a matter of course to prep it for the galvanize.
But, just taking or picking up stuff at the galvanize place gives both my helper and me headaches. I asked the old man that gave me a tour of the facility, what about the fumes? He said "Oh it won't hurt you. It only produces the bad fumes when you weld or cut it." I call BS on that. They have huge vats of melted zinc off gassing all the time. They keep it fired up 24/7, 365. If it is shut off the zinc will solidify and I believe the old man said it would crack the vats. Maybe he was only about 35 but looked 75 due to the harmless fumes. I hope he is tough enough to make retirement.
Just looking at the video of the hands applying the zinc to the beam makes me a little ill. I think it should be outlawed, period.
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