oxalic acid as grp cleaner - what dilution please

[Seajet]

I often taste chemicals to identify them, perhaps I had the same teacher.

I can already picture the inscription on your headstone !

 

[Hydrozoan]

I can remember when I used to pipette a 12.5% solution by mouth ...... several times over every day.

But you're surely young enough to have had one of those black rubber thingies?

 

[BlueChip]

I use it, slosh it all over, lewmar hatches, toe rail etc etc, no probs
Stu

I don't have any problem with Oxalic Acid and etching, but a two part Teak cleaner that I used after a recommendation on here made a real mess of my anodised ports and hatches.
Commercial oxalic acid deck cleaners are usually powder and sprinkled on wet decks and spread with a wet mop or sponge. Leave for about 15 minutes and wash off well.
My hull is blue and its really difficult to stop the acid causing streaks.
I have found that the best thing to use for mould and black spots is a patio cleaner with Boracol.
Costco sell 5 litres of a professional use formulation for about £20 used twice a year it works brilliantly, just brush it on a dry day and leave it.

 

[Hydrozoan]

[ QUOTE ]...oxalic acid seems to have gain the reputation as the magic cleaner for everything. The perfect solution for iron (rust) stains and the brown stain around the waterline, not forgetting its traditional use for wood bleaching, but every thing else ????????

I'd endorse Vic's point: a cleaning agent may be ineffective (or worse) in situations different from those which gained it a glowing reputation. Think carefully about the likely cause of a problem, and at the mode of action of any recommended cleaner. Obvious - but one can get carried along by sincere enthusiasms and beliefs.

I had a stubborn grey streak problem on the topsides and searched numerous boating forums without becoming convinced by the alleged causes - often, the aluminium of the toerail. So, I looked on caravan forums and found a poster who had noticed that there was no aluminium rail above the rear of his caravan, which nevertheless had heavy streaking (he kept the caravan on a sloping drive). He concluded that hydrocarbon deposits not aluminium were responsible, and chose a cleaning agent accordingly. It is a seemingly odd choice for boat topsides - but it works brilliantly for me.