Localised corrosion on steel boat

I find understanding cathodic protection very difficult once it goes beyond the basics but here goes with my version. I'll defer to anyone who knows better!
Too many anodes can cause cathodic disbondment around the anodes or where ICCP (impressed current) systems are used. Disbondment is seen as blisters in the paint scheme which, when opened, reveal shiny clean metal underneath. With anodes they are usually in a circle around the anode and the ability of the anticorrosive scheme to withstand disbondment is defined by the radius of the circle.
While cathodic protection system is working there is no corrosion problem although the paint scheme is breaking down. When cathodic protection stops corrosion sets in very quickly.
Disbondment can be avoided / reduced by increasing film thickness of anticorrosive scheme or reducing the oversupply of anodes / current.
 
Re: nope

The idea of cold tar epoxy I like, the only problem is I think it is too cold at the moment for epoxy. I think I'll use thixotropic bitchamin (spelling?) as I can put it on thickly and I'm comming out of the dock very soon.
Thanks for that.
 
Re: nope

so warm it up
I re bottomed an old tug and that was this time of year I used a heavy duty heater and covered the boat in a taup and warmed up the area where I was painting. Yours is easy you could heat from the inside while doing it the steel will be better protected

cheers
Mick
 
Re: nope

No, coal tar epoxy came off the market several years ago. Several companies sell synthetic versions but they are not as versatile as CTE. Some epoxies are very surface tolerant now and can be used at much lower temperatures than before but I would not attempt to apply with localised heating. Chances of a complete failure are way too high.
 
Re: nope

Don't know the product but very good I'm sure. Not coal tar epoxy though. It looks like one of the synthetic replacements.
 
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