could someone explain galvanising to me?

[haddles]

I've heard of cold gal, hot dipped, double dipped and kilrust in a spray can. How does galvanising work? What is the difference between the types? I don't know if kilrust is an international product but i'd also like to know how it 'kills rust'. My trailer isn't galvanised but it has about 20 coats of paint on it and seems ok.

 

[paulie0735]

Re: could someone explain galvanising to me?

Well to explain it simply, Galvanising accrues when steel is submerged in melted zinc, the chemical reaction tales place between the 2 metals permanently bonding the zinc to the steel, the zinc is not like paint because its not a sealer, it actually permanently becomes a part of it. Zinc is impervious to rust and corrosion.<br /><br />As for the terms used its more about how the treatment is applied more than the actual treatment, as you can imagine spraying it on is not actually altering the composition of the metal the way it might if its applied through the hot dip process. The spray can coating is simply a zinc coating. It will help protect any area that has been welded or scratched since the original galvanising was done but it is in no way comparable to the original process that your trailer went through when new. Trailers are galvanised after manufacture. Painting a galvanised trailer is purely cosmetic, as the paint will be long gone before the trailer rusts away.<br /><br />Where in Aus are you?

 

[haddles]

Re: could someone explain galvanising to me?

I'm in Brisbane. Not too much in the way of fresh water boating around here. The only fresh water my boat/trailer/motor sees comes out of the hose so it's a bit of a battle against corrosion.

 

[jtexas]

Re: could someone explain galvanising to me?

not much fresh water...so.......what do y'all make your beer out of?

 

[ztim]

Re: could someone explain galvanising to me?

Great advice so far. Rememer too that zinc chromate (spray) will stave off dissimilar metal oxidation. Did I say that right? Ok. Two metals that are different from each other will set up an electrical charge and rust will occur. That is why on airplanes you won't see aluminum on steel without the zinc protection. Anodizing is something totally different, but you may hear about it. For trailers though, go with the spray for small jobs. You can stop rust but not kill it (make it go away) if the damage was done. Stop it and then coat it. Good luck.

 

[ztim]

Re: could someone explain galvanising to me?

Great advice so far. Rememer too that zinc chromate (spray) will stave off dissimilar metal oxidation. Did I say that right? Ok. Two metals that are different from each other will set up an electrical charge and rust will occur. That is why on airplanes you won't see aluminum on steel without the zinc protection. Anodizing is something totally different, but you may hear about it. For trailers though, go with the spray for small jobs. You can stop rust but not kill it (make it go away) if the damage was done. Stop it and then coat it. Good luck.<br /><br />Dang it...posted twice.

 

[Eggkr8]

Re: could someone explain galvanising to me?

Hi,<br /><br />Galvanise is what they doin the UK and Aus, Galvanize is what they do in the States (hahaha)<br /><br />Galvanize is a process that electroplates Zonc on the surface of steel. Galvanneal is the process where the steel is dipped in hot zinc. I always remember is by you use heat to ANNEAL a weld.<br /><br />The electroplating method (galvanize) give you a better bond to the steel

 

[rwidman]

Re: could someone explain galvanising to me?

Trailers are galvanised after manufacture.

Or before, depending on the manufacturer. My trailer is bolted (not welded) together and was clearly galvanized before assembly. It doesn't really matter as long as it was done properly.