Can anyone tell me if it's a good idea to paint my stainless steel p-brackets with epoxy paint before antifouling ? someone said it's better not to antifoul, but what about those barnacles to say the least.
It's not really rustproof but relies upon a thin layer of impermeable chromate forming on the surface to protect it from further attack.
Putting epoxy on it is definitely a BAD IDEA as it will accelerate the corrosion underneath, which flourishes in SS in low oxygen environments.
In fact the most normal reason for stainless corrosion is crevice corrosion where the two sides of a crevice act as =ve and -ve sides of a galvanic cell - this can finish off a 12mm bolt in a season.
Antifouling, providing it is NOT a hard one is just NOT A GOOD IDEA. Hard antifouling is as bad as 2-part epoxy.
Interesting, I noticed at the Sealine yard in Hamble that quite a few boats S/Steel trim tabs were antifouled (the hard type I think). I also know a guy who has always antifouled his trim tabs to no ill affect for many years, so is it really a big problem. I was considering this myself until I read you comments, what other alternatives are there?
Although anti-fouled, my trim tabs seem to foul more readily than the rest of the "stern gear." However, fouling of the props has the greater effect on performance and trying to make a-foul stay on them is a challenge. I have a diver go down and inspect and/or clean the hull and running gear at intervals year-round. $50 a time for him saves me lot in fuel cost.
Er maybe it's the way I read it but you say
<<Putting epoxy on it is definitely a BAD IDEA>> <<Antifouling, providing it is NOT a hard one is just NOT A GOOD IDEA>> and <<Hard antifouling is as bad as 2-part epoxy>>
Does that mean the only sensible option is SOFT antifouling or nothing at all?
Sorry if I'm dense but we tried leaving a bit of our S/S trim tabs uncovered and the weed was alarming.
The secret is aeration - plenty of air happy stainless.
Certainly trimtabs really get fouled, mainly because they're wide open to sunlight - International are offering Micron 33 spray antifouling for the job (don't know how well it works), but I've never heard of trimtabs suffering galvanic corrosion, but P-brackets are a different matter.
Yes you should only use 316 A2 underwater - I had a 12mm castellated nut which fell apart in my hand after a season (it had been antifouled).
The original question was about using epoxy on P brackets - I would definitely and strongly recommend against that.
Try rubbing on your props and polishing, "black lead" the stuff used for old fireplaces and pot belly stioves etc. Works very well and doesnt come off easy an OLD trick, before hard antifoulings, the guys with the morcambe bay prawners, used to do the whole hull with it, for the "races" I use it on my props all the time, good stuff!
Polish on "black lead" used for potbelly stoves and old fireplaces, to make them black and protect them, works very well on props, comes as a paste, but make sure it is genuine black lead, not some boot polish stuff!