Rust stains on fiberglass deck

[boatman61]

And.. for those of you who hose your boat down most evenings after a day out so won't know.. you'll find they appear on long passages as well.. as the minerals in the sea water oxidise..

[savoir]

Time to give the damaged area an acid wash. It's a bit complicated but will work. You must do this out of sunlight in the early morning or late afternoon.

Grab some cheap dishwashing gloves, a cheap paint brush, a Scotch Brite pad, a bottle of muriatic acid and a plastic tub. Get a hose on deck and ready to use fast. Put on the gloves then mix 1 acid : 3 water. Brush on to the damaged area and wait 2 minutes. Hose off. You may need to repeat on the worst areas and use the Scotch Brite pad. Hose off with plenty of water.

Throw away the brush, pad and gloves.

[skipmac]

Originally Posted by savoir

Time to give the damaged area an acid wash. It's a bit complicated but will work. You must do this out of sunlight in the early morning or late afternoon.

Grab some cheap dishwashing gloves, a cheap paint brush, a Scotch Brite pad, a bottle of muriatic acid and a plastic tub. Get a hose on deck and ready to use fast. Put on the gloves then mix 1 acid : 3 water. Brush on to the damaged area and wait 2 minutes. Hose off. You may need to repeat on the worst areas and use the Scotch Brite pad. Hose off with plenty of water.

Throw away the brush, pad and gloves.

Just in case anyone isn't aware, muriatic acid is just another name for hydrochloric acid, HCl.

[Bob328]

I had the same problem. Used "a must for rust" that was available at home depot. Sprayed it on, waited 20 mins and washed it off with a hose. Worked great.

[Richfind]

I use Sno Bol toilet bowl cleaner. It is a gel so it doesn't run off to quickly. Cleans up brass and bronze also. It also is great at removing the brown stain that forms around the waterline. Don't get it on bottom paint.

[On Reflection]

I did something stupid too and I removed the rust specks all over my boat in a day with rust converter. Whack it on, let it sit and wash it down with fresh water. Couldn't be simpler.