Procote cold galv spray

[BruceDanforth]

A couple of years ago I painted my tabernacle with hammerite and some kind of rust converter and it didn't really work.

I have the rig down at the moment and I'm going to bash all the rust out with a cold chisel, clean it back to bare metal with acid then try this Procote stuff to 'cold galv' it.

It seems a lot cheaper than the Zinguard spray that the chandleries sell. I was wondering if anyone has tried this and if so did it work OK?

 

[BruceDanforth]

So if no-one has tried it what results have others had with cold galv in general?

 

[Rigger Mortice]

So if no-one has tried it what results have others had with cold galv in general?

FWIW I used a so called zinc rich primer on a non boaty job some time ago. It wasn't much good and I had the impression that it was a triumph of over optimistic marketing rather than sound paint technology. Nowadays I just use a good primer on metal followed by the top coats. Having said that I think the rust converters have some value on rusty metal.....but nowhere nearly as much as grinding back the rust when preparing the job.

 

[BruceDanforth]

I think this is different stuff:

http://www.toolstation.com/shop/Pai...ld+Galvanising+Spray+400ml/d150/sd2737/p60070

or

http://anodesdirect.co.uk/joomla/in...tegory_id=66&option=com_virtuemart&Itemid=124

 

[MM5AHO]

The term "cold galv" really is false advertising.
Galvanizing is an alloying reaction between iron and zinc. It only happens with molten zinc (mp=419C). There are several layers of differing ratios of Fe/Zn, and usually with pure Zn in the outer layer. Its electrically bonded to the steel, by virtue of being alloyed.

These spray paints contain zinc particles. The zinc has a small sacrificial effect, but because the individual particles are not electrally connected to the iron (they're bound up in the paint resin), the full electrolytic effect doesn't happen. This can lead at worst to the paint being no better at corrosion protection that any paint - merely a barrier coating. When perforated (scratch etc) the protection is broken.

 

[ghostlymoron]

I've used galvafroid for touching up galvanized steelwork. It doesn't seem to adhere very well and tends to come off in sheets.

 

[BruceDanforth]

How did you prepare?

I've used galvafroid for touching up galvanized steelwork. It doesn't seem to adhere very well and tends to come off in sheets.

 

[tr7v8]

Personally I'd use Rustoleum Combi Colour. Works very well & isn't brittle like hammerite so doesn't chip.

 

[ghostlymoron]

How did you prepare?

Not very well. It was done by electricians on galvanised cable tray. It stayed on until the client had signed the takeover certificate but didn't usually last until the 12 month warranty was up.

 

[BruceDanforth]

Well I spent most of the day grinding the rust out of the tabernacle with a dremel - a much filthier job than I anticipated and I was like a coal miner by the end of it. The rust was several mm thick in places but I still have plenty of metal left in the tabernacle.

I will get rid of the last bits of rust with acid tommorow then think about paint.

 

[John the kiwi]

Probably too late now, but i wonder if your effort may have been better spent in removing the tabernacle completely?
Hard to know without seeing the job, but sometimes apparently large and daunting jobs are not that bad when you get stuck into them.

Once removed of course you could have it shot blasted and hot dipped which would probably take care of it for 5- 10 years or get a copy made in stainless steel which would take care of it at least for the life of the boat.

I remain dubious about any paint applied to a non shot blasted steel surface.

Good luck with whatever you choose.

 

[BruceDanforth]

Removing it and getting one made up in stainless or hot dipping it is in the long term plan but right now I just want it tidied and protected for a couple of years until the next time the mast is down. I am hugely over budget for this round of refitting already...

 

[MYStargazer]

A couple of years ago I painted my tabernacle with hammerite and some kind of rust converter and it didn't really work.

I have the rig down at the moment and I'm going to bash all the rust out with a cold chisel, clean it back to bare metal with acid then try this Procote stuff to 'cold galv' it.

It seems a lot cheaper than the Zinguard spray that the chandleries sell. I was wondering if anyone has tried this and if so did it work OK?

Any joy with this stuff? Has it adhered well? http://www.toolstation.com/shop/p60070

 

[BruceDanforth]

No, it was ****!

It adhered well but seemed more like lampost paint and started showing rust spots in days. I went back to hammerite in the end.

Bah!

Any joy with this stuff? Has it adhered well? http://www.toolstation.com/shop/p60070

 

[MYStargazer]

No, it was ****!

It adhered well but seemed more like lampost paint and started showing rust spots in days. I went back to hammerite in the end.

Bah!

Much appreciated, thanks!

 

[Gordonmc]

Probably too late now but the best metal prep I have found is Zinga.
Zinc in a form of resin which is painted on, not aerosol.
I used it on my engine bearers, then painted over with smooth Hammerite.
Still good.

 

[HunterWanderer]

Ive used similar paints to Procote with very good results. It really acts as a good inhibitor due to the zinc.

It is just a primer though so will need a good topcoat. Perhaps Hammerite.

I have used it on my keel which was very badly corroded. I did grind off the surface though with an angle grinder but there were lots of cavities that were still present. I used a spay zinc coating then overcoated with west epoxy and has lasted 8 years now without any problems.