Galvanizing Spray

[Hankthelank]

Hi,

Has anybody used the galvanizing spray from west marine? I have some zinc plated brackets which I would like to use for shelf support in a battery locker, and think that zinc plated would not stand up to hydrogen corrosion. This spray is supposed to be as good as hot dip galvanizing (so the manufacturer claims). Any reviews?
Hank

[svquest2]

Never used the spray but I have used liquid paint. That worked Okay but it's not as good as hot dipping because in the difference in thickness. I would think that the spray would be even thinner. It acts the same as hot dipped but it won't last as long.

Good luck

Joe S

[Boracay]

I've often been disappointed with galvanising paint/spray.

I think the problem is that as many items come from the factory there is a shinny surface with small amount of grease on it. Many paints will not stick when this happens.

If I think there is any grease on anything that I want to paint I use a degreaser.

A light sand with fine emery paper followed by a good quality etch primer could work wonders.

Follow that with a quality metal paint. Maybe even a galvanising one.

[GordMay]

Cold galvanizing sprays are zinc, like your plated brackets.
Better products contain over 90% zinc, and will work ok in your application (low/no abrasion).

[Cadence10m]

I've JUST used two cans on my emergeny tiller and other spots. So I don't have any info on how long it stands up, but my father-in-law said he used to sell the stuff to industrial customers and that it's "good for two years".

We'll see.

Craig

[rocklobster]

I have some significant industrial experience using paint laden with zinc. If applied properly (so that it sticks to what you apply it to) then a cold application coating can work quite well. The key to longevity is building up enough coats of zinc. The more zinc, the longer it will last. I have done extensive ASTM salt spray chamber testing to compare zinc rich spray and liquid paints to hot dip galvanizing over black steel and the key to longevity is coating thickness. Typical galvanized sheet metal is usually applied between 0.9 and 1.2 oz/sq ft, hot dip galvanizing is usually much greater, 2.4 oz per sq ft or more, depending on how slowly it travels through and is pulled from the kettle. If you build the spray coating to a coating thickness of 2.4 or greater than 2.4 oz per sq ft you will have a pretty good zinc coated part, comparable to typical hot dip galvanized coatings. Not all spray zinc or liquid paint zinc paints have equivalent amounts of zinc. Check the label or contact the manufacturer and do the math. For example, if the contents weigh 16 oz and is 90% zinc and you coat 1 sq ft with the entire contents of the can then you have applied 14.4 oz per sq ft, over 10 sq ft this same can would supply 1.44 oz per sq ft. Keep in mind, regardless of whether it is sprayed or dipped, strong acids or alkalis will attack the coating and reduce its effectiveness.

[David M]

I use galvanizing spray paint on some large hydraulic cylinders on my afterdeck. It seems to work pretty well so long as you keep after any dings in the paint or anywhere you see rust starting to bleed through.

If you have ever dipped something with zinc plating in sulphuric acid, which I have, the zinc comes off real quick...like within a few minutes. I would epoxy coat the bare metal rather than relying on zinc paint which in all likelihood will not last very long in that type of an environment.

[lorenzo b]

Also available at home depot and any hardware store, used extensively by iron workers that have to field weld galvanized iron such as handrails or spiral stair units. Get the surface clean and spray several times and then topcoat with good paint.

[Cheechako]

It doesnt work on anchors... :>)