Hi, We bought a used TT recently, only 3 yrs old, but the previous owner left it sit in his driveway for a long time where the lawn sprinklers regularly hit the bottom couple of feet of the smooth fiberglass finish. We have successfully removed some of the water mineral stains, but the last bit where it got sprinkled the worst is stubborn.Can anyone suggest some cleaning materials to use to remove the mineral water stains without damaging the smooth fiberglass finish? Obviously anything abrasive is not an option.

Some mineral stains are harder than others. I would try vinegar and rubbing, after washing to get all other dirt off. Don't want to grind it in.Be sure to rinse it good and not let it stand on aluminum or other metal or the paint, if that is what is on the fiberglass or gelcoat.I had a dickens ,of a time, getting it, off the side, of our MH when, the plug on the water heater decide to leak.Might ask Mfg first off.I hope someone here has a product, in mind that works better and easier. Keeping our rigs clean is a chore.

I would try a small inconspicuous spot with Bar Keeper's Friend. It is pretty amazing stuff. My guess is it will be safe for the fiberglass but get rid of the stains.

Jasco brand pre-paint cleaner and conditioner, TSP, vinegar, or anything with an acid base, preferably phosphoric acid. Water softener liquid conditioner really eats away mineral and rust but you're working with a strong acid. If used, obey all safety precautions.

Thanks for all the suggestions, everyone! Appreciate it! Please keep 'em coming!I have never used Barkeeper's Friend -- I thought it was a mild abrasive. No?

Try using CLR;http://www.jelmar.com/CLRbasic.htm

Mineral Water Stains on Smooth Fiberglass Exterior

13 Replies

westend
Explorer
Apr 07, 2014
Jasco brand pre-paint cleaner and conditioner, TSP, vinegar, or anything with an acid base, preferably phosphoric acid. Water softener liquid conditioner really eats away mineral and rust but you're working with a strong acid. If used, obey all safety precautions.
TucsonJim
Explorer II
Apr 07, 2014
I would try a small inconspicuous spot with Bar Keeper's Friend. It is pretty amazing stuff. My guess is it will be safe for the fiberglass but get rid of the stains.
down_home
Explorer II
Apr 07, 2014
Some mineral stains are harder than others. I would try vinegar and rubbing, after washing to get all other dirt off. Don't want to grind it in.
Be sure to rinse it good and not let it stand on aluminum or other metal or the paint, if that is what is on the fiberglass or gelcoat.
I had a dickens ,of a time, getting it, off the side, of our MH when, the plug on the water heater decide to leak.
Might ask Mfg first off.

I hope someone here has a product, in mind that works better and easier. Keeping our rigs clean is a chore.

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Mineral Water Stains on Smooth Fiberglass Exterior

13 Replies

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