Cold Galvanizing Compound

I spray my props with Rustoleum Cold Galvanizing Compound at every haul out. I "think" they don't support as much growth. My diver agrees they look better. It's cheap enough and causes no harm that I know of.

This season I used the same ablative paint as on the bottom. Only a tiny fraction of the growth as in post 22.

Anyone cold galvanized anchor chains?

I use it to touch up my chain and anchor everyseason...never seems to wear like the hot dipped stuff (OEM)

I have used the Rustoleum cold spray (no primer) for 5 seasons and it lasts our full season (about 5-6 months) here in the Long Island sound with almost no growth. Since our boats do plane we find out pretty quickly when the rotating parts have any growth on them>
2 cans give two good medium coats on the 21 X 24 props and the SS shafts.
In the past we have used various other methods including prime and bottom paint, 'special' prop sprays, penaten and a few others.
The cold galvanize was the best for us and happened to be the most economical as well - prep is required before the spray for good adhesion.

I have actually done a direct comparison of the Pettit and Rustoleum Cold Galvanizing spray products. It was carried out in the relatively brackish waters of Portland Harbor and cold waters of Casco Bay (Maine).
When I first purchased my current boat four years ago (a twin engine GB 36 Classic) the props were covered in barnacles. On the advice of another boater owner friend, I used the Pettit spray the next year. One prop got two coats and the other got only one. The shafts got none. When the boat was pulled in the fall, the prop with two coats look pretty good. The prop with one coat not as good and the shafts were bad. The next year I put three coats of the Pettit spray on one prop and shaft and three coats of Rustoleum on the other prop and shaft. That fall both props and both shafts were barnacle free - not a one. There was absolutely no difference between the two products.
In summary - the two products performed equally well but the coverage (number of coats) appears to be important. One added, unexpected advantage was a longer sacrificial zinc life. My shaft zincs were barely worn. In hindsight, I suppose this should be expected. These sprays are just another way to apply a sacrificial zinc.
This year I am trying the Rustoleum on the struts and trim tabs as well.

While I can't say the galvanizing paint does or doesn't work...because my experience and others is far from scientific...


I will say that I too believe that a healthy coat on shafts, props and rudders, whether topped with antifouling or not...does seem to help my zinc anodes too.


Not scientific but painting underwater metals does usually slow down any galvanic action.