Oxalic Acid

I've used Oxalic acid and it is a real faff to use and takes ages, keeps falling off the hull it comes mixed in a wallpaper paste type stuff.

I don't know what you want it for but usualy its for removing the horrible brown stain from the waterline, I was recommended "Spirit of Salts" by a boatyard who do it all the time and it is massively better and it took no time at all, its a bit toxic (don't breath near it) but only £3 a bottle:) Try Drews the hardware shop chain. Wouldn't reccomend it for cleaning a whole boat just stubborn small stains.
 
Spirit of Salts ?

Spirit of salts is Hydrochloric acid - very strong stuff. I wouldn't want that anywhere near my boat. We used to use it for cleaning very stained toilets during my time as a cadet.
 
Spirit of salts is Hydrochloric acid - very strong stuff. I wouldn't want that anywhere near my boat. We used to use it for cleaning very stained toilets during my time as a cadet.

Yes it is strong but it works doesn't touch plastics or grp though, unfortunatley anything that actulay does the job its supposed to usualy has XXX scull and crossbones on the side:)
 
I've seen lots of threads and posts on this subject - is it really as good as it seems, and where can you buy the stuff ?


It is an organic acid made from Rhubarb leaves. We use it in the building industry to remove certain salts from brickwork.

It comes as a powder and you mix with water till no more will disolve. To the best of my knowledge you can buy it from a decent Chemist.
I have never tried it on boats though !
 
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Yes Oxacylic Acid is very good.

Its the main ingredient in a lot of expensive boat cleaners.

Buy it cheap in bulk from Ebay and mix it yourself.

ALWAYS WEAR GLOVES otherwise your skin on your hands falls off for a week afterwards (learnt the hard way). Spray it on with a garden sprayer or paint it on.

If you cannot be bothered mixing it up yourself then a weaker form is the principle ingredient in "Cillitt Bang" which is available at your local Supermarket. I used the real thing once and then just keep the boat topped off using Cillitt Bang.

Martin
 
1 heaped tablespoon with about 3/4 pint of water and off you go.will clean the yellowing off a white hull near enough instantlywith a 2"good quality brush.done about a meter and a half at a time and rinsed off immediatly.great stuff and cheap too.as stated above is the main ingredient for all of the expensive gels that you can buy but would recommend glasses and long sleeves and keep a bucket of water and a sponge close by to rinse off.replenish it regularly.polish hull as soon as good enough.i bought about a 1/2 pt mugs worth and it will last about the next ten years.
 
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If you cannot be bothered mixing it up yourself then a weaker form is the principle ingredient in "Cillitt Bang" which is available at your local Supermarket. I used the real thing once and then just keep the boat topped off using Cillitt Bang.

Reckitt Benckiser market a number of products under the name "Cillit Bang"

The relevant one for this purpose is Cillit Bang Grime & Lime

It does contain oxalic acid but the main ingredient is in fact sulphamic acid. A weak acid but somewhat stronger than oxalic acid.
It also contains formic acid.
 
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