Acid Rain?

[robp]

During the past few weeks I've spent hours on end cleaning off and polishing the GRP topsides. I got it as clean as possible with Flash and a soft scratchy pad, then brush scrubbed all the non slip horizontal surfaces, so there would be no dirt to run. Then I used Myrh (sp)? to finally clean and polish.

Next visit and all vertical surfaces have black streaks down them! Also, it doesn't rub off that easy. Is the non slip still dirty, or does the wax attract the cr*p? Looking around, it appears that most other men's (person's) grass is greener and GRP whiter. Any ideas?

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[Robin]

We have the same problem (Poole based). I washed the decks last Wednesday with Starbrite Non Slip Deck Cleaner (excellent for the moulded non slip) and by Friday pm they were dirty and there was black 'dust' deposited on the side decks where puddles before it runs over board. We have in the past had red dust (we were told the rain contained sand from the Sahara!), currently there is lots of building work locally so maybe that is the black crap source? Our coachroof was cleaned and polished in March with a high peformance polish but is already ingrained with grey grime/black streaks from the rain and needs doing again, soapy water doesn't shift it nor does the deck cleaner. Since our decks/coachroof are white they do show the dirt more than others, but boats nearby are also suffering. I would love to know the answer!

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[extravert]

Boats in Pwllheli get black smears down them in the cooler part of the year, because a lot of the local houses use coal for heating. Where are you? Could this be the cause?

<hr width=100% size=1>One day, I want to be a real sailor. In the mean time I'll just keep tri-ing.

 

[robp]

Thanks for the suggestion but no, I'm in smokeless Chichester!

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[smee]

Have you got black window rubber edges that could cause it. I had a Foxcub with black window edges and they ran like mad, all over my lovely MER'd topsides! And trying to clean it off just spread grey patches everywhere!!

I suppose even if you have deck fittings with black sealants hidden underneath it could cause it also! You wouldn't necessarily be able to see them, but the water would find it!!

Just thank your lucky stars you don't moor in Spain where every downpour is Gadafi's revenge - mind you maybe it is politically incorrect to call all the horrible red muck that, these days!!!

They sell stuff called Black Streak remover now...... its probably all a quiet conspiracy between boat builders and boat cleaner manufacterors to make sure people keep buying the goods!!!

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[robp]

No, there are no sealants or rubber near the offending marks. It just comes down off any horizontal surface and mainly the moulded in non slip. Either it's in the rain or it's because I didn't get all the non slip clean enough, although it looks it!

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[ChrisE]

I'd take a guess and say that as you are downwind of Portsmouth (usually) you are getting the fallout from when the ferries start up. Boats on the Lymington trots are regularly showered with smuts from the ferries in the river, the nearer the ferry the worse it is.