Oxalic acid

[misfits]

TSP, can't be that bad.
It's used in the mechanical trades to flush piping on heating & chilled water systems during commissioning. That gets dumped into the sewer.
Can't put hazardous waste down a sewer.

[john61ct]

Occasional use by licensed professionals is different from

constant use by large populations

the solution is dilution

Yes household products should be well regulated to help protect the environment

[AKA-None]

And the darned fertilizer people poor all over their lawns.

[HopCar]

Originally Posted by Paul L

You have fiberglass mites?

I have bees. The bees have mites. Oxalic acid vapor kills the mites and not the bees, if you do it right.

Now fiberglass eating termites are a whole other problem.

[grecko]

I use Barkeepers Friend also and it works relly well.

[stormalong]

Originally Posted by AKA-None

And the darned fertilizer people poor all over their lawns.

Home yard & garden fertilizer is not the problem.

Farm runoff from millions of acres of farms is. So is animal waste from huge feedlots.

[RaymondR]

Originally Posted by Scatterling

Does it damage the antifouling where it runs down?

I don't know, I used it to clean the hull after I had water blasted the ablative antifoul during my annual slipping so there wasn't much there to damage.

[Uncle Bob]

Originally Posted by HopCar

I have bees. The bees have mites. Oxalic acid vapor kills the mites and not the bees, if you do it right.

Now fiberglass eating termites are a whole other problem.

Good luck with the extermination, there's not many places left in the world that don't have the little ba****ds. When we lose the bees we lose so much !!

[bobs]

Have used oxalic acid for years now, awesome stuff , very efficient and it also gets that yellowish layer on the bow/upper hull off in no time .
I have a jar crystals , take a spoonful and add some warm water to it to make a kind of gel . Put it on the rust stains and leave it on for a day or what ever .
Just rinse it away afterwards , job done .

Regards

[B4A]

Originally Posted by bobs

Have used oxalic acid for years now, awesome stuff , very efficient and it also gets that yellowish layer on the bow/upper hull off in no time .
I have a jar crystals , take a spoonful and add some warm water to it to make a kind of gel . Put it on the rust stains and leave it on for a day or what ever .
Just rinse it away afterwards , job done .

Regards

Have you used it also for cleaning the deck or just the hull? My question is if it can damage the gelcoat.

[Group9]

Originally Posted by Scatterling

Does it damage the antifouling where it runs down?

Yeah, and it dissolves wax finishes, too. And, galvanized/zinc finishes. Definitely at the upper end of power cleaning agents.

[bobs]

No , it will not damage the gelcoat , in some cases I just forgot all about the oxalic-gel on some rust spots for days , to find all the rust gone and the gelcoat pristine .
Don't worry .

Regards

[Paul L]

Originally Posted by bobs

No , it will not damage the gelcoat , in some cases I just forgot all about the oxalic-gel on some rust spots for days , to find all the rust gone and the gelcoat pristine .
Don't worry .

Regards

If your gelcoat is other than pure white, oxalic acid left on too long can leave a bleached whiter stain.

[HankOnthewater]

Originally Posted by Scatterling

Does it damage the antifouling where it runs down?

When one applies the acid solution to the hull, one can see white streaks on the antifoul, where the solution runs down, particularly on antifoul above the waterline, but I have never found this to damage the antifoul properties.
As said before:
- it strips all the wax off the hull, not sure about silicone 'wax' products, so an acid wash of the decks and hull when the boat is out of the water before antifoul and a wax job..... Ideal, I would say.
- it marks / bleaches (unvarnished/oiled) timber, but over time ie months, this bleaching disappears

Additional comments:
* An acid solution woks equally well with salt water! I mean, I can not see any difference between salt and fresh water. Maybe fresh water solutions can be made stronger?
* Water does not need to be warm. However one can dissolve more acid in warm water, but the acid is strong enough in cold water.
* I have often a small container with an acid solution that I use to throw in rusty nuts/bolts/tools etc, leave them a few hours or overnight; mostly items come out shiny.
I have been using oxalic acid for 25 years.

[Jim Cate]

If all one is doing is removing minor rust stains and yellow grunge above the waterline, sounds like you are all mixing much stronger solutions than needed. I use around 2-3 tablespoons per gallon in a garden sprayer. Spray on, leave for 10 minutes (about the time it takes to walk around the boat spraying as you go) and hose off. No damage to anything, no bleaching of finishes, no worries!

Jim