Oxalic acid

[B4A]

Does anyone here use oxalic acid to clean fiberglass decks?

[Paul L]

Yes, to clean rust and related stains

[HopCar]

I going to use it to kill Varroa Destructor mites. Yes it’s also a pretty good rust stain remover for use on fiberglass.

[Paul L]

Originally Posted by HopCar

I going to use it to kill Varroa Destructor mites. Yes it’s also a pretty good rust stain remover for use on fiberglass.

You have fiberglass mites?

[psk125]

Originally Posted by Paul L

You have fiberglass mites?

Those are called polyestermites. Oxalic acid is useless against them. You need an acetylene torch.

[RaymondR]

Used it for hull cleaning, sprayed it on and hosed it of about five minutes later, did a good job, definitely my kind of product.

[Scatterling]

Originally Posted by RaymondR

Used it for hull cleaning, sprayed it on and hosed it of about five minutes later, did a good job, definitely my kind of product.

Does it damage the antifouling where it runs down?

[Cheechako]

Originally Posted by Scatterling

Does it damage the antifouling where it runs down?

It can yes. You may see copper color stripes in your paint.
For heavy duty cleaning I use TSP (Tri Sodium Phosphate, the home pre paint cleaner) in a shaker can with a brush. Stuff is amazing at cleaning fiberglass.
Warning: Use rubber gloves! You wont feel it until a couple hours after use but your hands will be burn't.

[hellosailor]

TSP?! Oooh, my home state is one of many that regulated it out of Spin'n'Span and other consumer products. Too much nitrogen or phosphorus runoff into the waters, they said.

[Cheechako]

Originally Posted by hellosailor

TSP?! Oooh, my home state is one of many that regulated it out of Spin'n'Span and other consumer products. Too much nitrogen or phosphorus runoff into the waters, they said.

Yeah, Don't know if Oxalic is as bad or not. TSP is in powdered laundry detergents, (or was?) they work pretty well too. Not much out there like TSP though.
https://www.bobvila.com/articles/cle...ium-phosphate/

[stormalong]

Most fiberglass cleaners, such as FSR are just gelled oxalic acid. Usually watered down to make them less irritating to your skin. I buy wood bleach crystals from my local hardware store and mix my own. It is a great cleaner for fiberglass. It strips away the old wax and those tannic acid stains you get going down rivers and inland waterways. You do need to wax the hull again after using it.

[hellosailor]

"You do need to wax the hull again after using it."
Same as Spin'n'Span, used to clean and strip linoleum floors, beloved by janitors and housewives everywhere.(G)

Cheechako, I don't recall if it was just a big deal in the states bordering LI Sound, or if it was a federal thing. Just that for those of us in the NE, detergents got reformulated to be zero-TSP, low phosphorus, etc. probably back around 1990.

Then I hear about places like Floridia, where they are having both red and green algae blooms (ooh, xmas colors! Chinese festival colors!) and the state just can't figure out how to possibly deal with that....ergh, I guess political leaders aren't required to read recent history books, huh? (sigh)

Who would have ever thought, the government would need to regulate LAUNDRY DETERGENT?! Does this mean there should be a California cancer warning label on Fels Naphtha Laundry soap, because of that magic ingredient too??

[Vasco]

Originally Posted by stormalong

Most fiberglass cleaners, such as FSR are just gelled oxalic acid. Usually watered down to make them less irritating to your skin. I buy wood bleach crystals from my local hardware store and mix my own. It is a great cleaner for fiberglass. It strips away the old wax and those tannic acid stains you get going down rivers and inland waterways. You do need to wax the hull again after using it.

Used to do this now use Barkeepers Friend in powder and cream it's just oxalic acid.

[roverhi]

Most of your teak cleaners, Bartender's Friend, and rust stain removers have Oxalic acid as an active ingredient. First started using it in the '70s to remove rust stains on the hull from external chain plates. Mix the Oxalic crystals with water and paint on the rust stains, wait a few minutes, wash off and the stains were gone. Makes a good wood bleach if you have stains on wood that want to finish bright. I bought a 25# bag of it from a commercial chemical supply place a few decades ago. Just rediscovered the glass jar I had the remains stored in. Will have to mix up some and see if it still works.

[thinwater]

a. Oxalic acid. present in some foods, certainly biodegradable, but irritating to the skin.
b. TSP (trisodium phosphate) contains phosphorus, but not nitrogen. Just avoid runoff. Dilulue the waste and pour it in the grass (fertilizer).
c. Barkeeper's Friend also contains a attractant and an abrasive. It will wear surfaces away if overused.
d. Lactic acid (CLR) is a good alternative to oxalic acid, similar in many ways and less corrosive to aluminum and skin. I've diluted it in a spray bottle and used it to clean the hull; works well and very safe.


(oxalic acid formula)