GRP hull stain remover

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ripvan1

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Whilst googling I came across a suggestion to use a baking soda paste, anyone ever tried this or got any other ideas that do not entail chandlers' products.

Thanks
 
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any acid will pull out the brown staining from GRP - commercial hull cleaner (Starbrite for example) is Hydrochloric I believe.

then there's B&Q brick cleaner - Sulphuric

and many more.

however there are rules and regulations, let alone safety implications, and you should investigate all before taking this approach.

typically you would mix a little wall paper paste in with the acid for hull cleaning as it works better and is more economical (with the acid)

commonly there are acid crystals you can get from a chemist and make up your self - A something but my alzheimers is preventing me remembering (and I have used loads!) - remembered it's Oxalyic
 
duncan said:
any acid will pull out the brown staining from GRP - commercial hull cleaner (Starbrite for example) is Hydrochloric I believe.
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Starbrite Hull Cleaner is oxalic acid - less than 10% acid, incidentally.

I think it's very irresponsible to suggest using "any acid".
 
pvb said:
Starbrite Hull Cleaner is oxalic acid - less than 10% acid, incidentally.

I think it's very irresponsible to suggest using "any acid".
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And brick cleaner is sometimes hydrochloric acid. ( Pretty sure B&Qs own brand is) Never sulphuric AFAIK

Cillit Bang Lime and Grime is acid ( Sulphamic IIRC) and will work I beleive.

Scale removing toilet cleaners will also.

Y10 is the common oxalic acid based hull cleaner.
You can make a substitute by thickening an oxalic acid solution with wallpaper paste.

Take care though some of these may be harmful to the marine environment
 
pvb said:
Starbrite Hull Cleaner is oxalic acid - less than 10% acid, incidentally.

I think it's very irresponsible to suggest using "any acid".
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Firstly I don't think I said that at all, I said any acid would pull out the brown staining, and went on to highlight the wide range of considerations necessary before using any acid.

The Starbrite barnacle version is Hydrochloric Acid.
 
nigelmercier said:
If you are talking about brown rust stains, you need Oxalic Acid. Just buy the crystals and make your own, 100g per litre.

Wear gloves and eye protection, and don't get it mixed up with the sugar! :eek:
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+1 to oxalic acid for cleaning topsides and decks. I got mine on eBay - a kilo cost £6.50 and did a 34 foot boat, topsides decks and all.

You need to mix it with warm water so it disolves then apply it with a Vileda sponge mop or similar, you don't need to rub it in or anything just get it wet. Then leave for 10 mins or so and rinse. Very easy and works unbelievably well on hull staining, rust stains etc.

Boo2
 
I bought some International Gelcoat stain remover from a chandlery in Dunquerque. Works very well and not too expensive. The instructions are in most European languages but not in English. I have not seen this product for sale in the UK. Presumably our overzealous application of Health and Safety legislation bans it from sale here.
I used to use Kreme Cleaner, also good, but that's vanished as well; also some blue powder in a yellow container which was very good (can't remember the name).
Anything that works well seems to be banished!!
Why hasn't the BMF made a fuss about over zealous rules, if that't what it is.
Hopefully I'm off to Dunquerque next Friday and will restock!!
 
thanks all, think i will try baking soda paste and then sillet bang out of curiosity then oxalic acid. i'm prone to panic attacks when entering chandleries
 
ripvan1 said:
thanks all, think i will try baking soda paste and then sillet bang out of curiosity then oxalic acid. i'm prone to panic attacks when entering chandleries
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I'd start with the oxalic acid first, it's magic stuff. just have the patience to leave it on long enough to work. Could save you some time.
 
ripvan1 said:
thanks all, think i will try baking soda paste and then sillet bang out of curiosity then oxalic acid. i'm prone to panic attacks when entering chandleries
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I really doubt if baking soda will work ... but try it and lets us know if it does.

If you go for Cillit Bang remember it's the "Grime and Lime" one you need.
It contains sulphamic acid, formic acid and oxalic acid amongst other things
 
Dirty Talk !!

I have just bought some Oxalic Acid powder from e-bay, cost the thick end of 3 quid for a big tube, will try this weekend and report back...I have 'Kent' mud stains, diesel stains, rubber stains from the dinghy rubbing strake etc....etc....

Instructions say add warm water and spray on to affected area and leave for 20 mins...then wash off....what can possibly go wrong?

I'll let you know.
 
Goggles, Hard Hat, Steel Boots and a Cricket Box will be worn !

Nooo problem Booo ....As a 'health and safety nut' all necessary precautions will be taken....I may even read the instructions ;¬) ....seriously , yes, it looks like quite iffy stuff...I wonder if it's the same 'oxy' that gets put into the washing machine and costs a hell of a lot less...any one know?
 
Money Saving Hint # 35

ripvan1 said:
thanks all, think i will try baking soda paste and then sillet bang out of curiosity then oxalic acid. i'm prone to panic attacks when entering chandlers
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Baking powder.. pound/for/pound will work out hellish expensive compared to the other remedies recommended...I'm trying oxylic acid £3+ for a big tube...I guess it will be more than enough for my 19' Mirror Offshore
 
I make my own grp cleaner.
Oxalic acid crystals, 100g per litre of hot water, and about 50ml of Fairy Liquid. (any detergent will do)
The purpose of the detergent is twofold.
It helps to see which area you have done, and foams a little (or a lot with a brush), indicating the covered portion, and slows down evaporation.
Secondly, some things don't come off with acid and the dtergent shifts a few things too.

So this green goo, which becomes a foam with brushing should be left on about 10-15 mins, then hosed off.

Did the complete topsides last week when we ran out of wind. White!
 
I wonder if it's the same 'oxy' that gets put into the washing machine and costs a hell of a lot less...any one know?
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No not if you mean the "oxy action" bleach like Vanish. That contains a peroxide that releases oxygen.

This is oxalic acid, one of the stronger of the weak organic acids.
It is:
harmful if swallowed, inhaled or absorbed through skin;
corrosive - causes burns,
very destructive of mucous membranes
and may cause congenital malformation in the foetus.

It is the substance which makes rhubarb leaves poisonous.
 
Brilliant idea....never thought of that...no chemical reaction between the Fairy and the acid then ? I often read that you should not combine cleaning products as the combination can give off toxic gasses.....obviously not I guess...

once again many thanks for the reply...

Cheers.
 
VicS said:
No not if you mean the "oxy action" bleach like Vanish. That contains a peroxide that releases oxygen.

This is oxalic acid, one of the stronger of the weak organic acids.
It is:
harmful if swallowed, inhaled or absorbed through skin;
corrosive - causes burns,
very destructive of mucous membranes
and may cause congenital malformation in the foetus.

It is the substance which makes rhubarb leaves poisonous.
Click to expand...

Oh dear...now you've gone and spoilt it....what with me being 'Mr health 'n' safety!' an all.... ;¬) So far as I only will ever drink a cup of tea whilst wearing a full immersion suit, hard hat, steel boots and Cricket box..... in a vacuum...

Seriously...thanks for the 'heads up' on the H&S issues...but apart from destroying my 'mucous membranes', (oooeerrr missus !) , and destroying my as-yet unborn spawn.....what can possibly go wrong ??

Cheers.
 
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