Brown Stain above Water Line

Spartan

Spartan

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Hi guys,

I'm pretty new at owning a yacht and about to put her back in the water after a winter in the boat yard.

However, when cleaning her last weekend, I noticed a brownish dirty looking stain right along the hull, just above the water line. I recall seeing it when we took her out in October - but forgot about it.

Is there an easy way to remove these stains ? Assuming there is, what would you suggest that I buy to bring the hull back to the gleaming white colour it should be.

Thanks for any suggestions.
 
Oxalic Acid. Available as a gel from chandlers. Y10 is the most popular, but it's not cheap.

If you feel like a project, buy it from your local pharmacy in crystals, mix up in a bucket with water and some wallpaper paste. Dab it on with a brush, leave until the white re-appears, then rinse off.

You'll end up with so much mix you can share it with everyone else in the yard!

It can also clean & restore stained wood.

It's poisonous, so wear gloves and goggles when mixing and applying.
 
If you have applied new antifouling, take care to keep the acid off it or you will have more to do.

Most people use a what we cal a 'boot topping' another line above the waterline.

It can be hard antifoul paint that you can scrub, tape that is replaced when needed, or other paints.

Hope this helps.
.
 
Second the rec. for Oxalic Acid.

Pre prepared mixes like Y10 are very expensive. Ebay is your friend (£2.99)

http://cgi.ebay.co.uk/Oxalic-Acid-D...Equipment_Lab_Supplies_ET&hash=item20adae9ffe

just search for Oxalic acid.....

Forget the wallpaper paste. Just make a solution (add acid to tepid water, not the other way round). I always just keep adding a bit more till you have crystals that won't dissolve and then just paint it on with a brush or wipe with a sponge. Leave for 15 mins and hose off. Sharing it round the yard is a good plan. I have a 500g tub that did 3 boats this Easter and I still have around 200g left....
 
1/2 pot of Y10 for ~£14 was enough to do a 36' hull .... and more than one coating in places ...
Yes - you can faff about, but sometimes it's worth paying for simplicity! ;)
 
Hello,

Y10 has been recommended to me.

I'm new to boat owning too. Any ideas what caused your Brown Stain ? Mine appeared the first time I watched them lift out and chock off my pride and joy.
 
It's just the first stage in the fouling process and occurs where the water slops up above the waterline. Fouling is a complete food chain! These first bits are mico-organisms, etc. upon which later arrivals will feed and take root.

Rob.
 
Starbrite Hull Cleaner has always done the job for me and is very easy to use. Not too expensive either.
 
Bear in mind that these stains are a deposit and have to be cleaned off to do the job properly.
Yes Y10 and similar will work well to make it look better, but it is only a bleach and the stain will return very quickly and worse.
I said above, the ceramic hob cleaner works well as does Cillit Bang suggested by Andrew, you really needd something to scour the surface, without damaging the gel coat of course. ;)
 
fireball said:
1/2 pot of Y10 for ~£14 was enough to do a 36' hull .... and more than one coating in places ...
Yes - you can faff about, but sometimes it's worth paying for simplicity! ;)
Click to expand...

Gosh.

How thick are you putting it on?

I'm only on my second pot - in 15 years, and it is still half full.
 
I have a patch of brown stain which I have applied 5 times with Y10, Tcut and polish and it is still there! Not the usual waterline mark, could poosibly be a tea stain where a former owner emptied teapot over the side perhaps. A sod to shift.
 
Brown stain above waterline

I found most acids will dissolve the stain. So while oxalic acid or phopsphoric acid as in rust converter are best I found lemon juice will also clean it. Vinegar might do it also. It dissolves in about 3 minutes then wash it off and apply more if necessary. A very satisfying job as you can quickly see the improvement. olewill
 
Thanks all - that's a great help.

Looks like I now know what to buy and try. All I need is a dry weekend to have a shot a getting rid of the stains. At least I now what to try.

Wonder if the family will help with the hard work ? :rolleyes: I think I already know the answer to that one ! :(

Much appreciated everyone who bothered to respond. Cheers.
 
You can buy expensive stuff from chandlers, make up your own using oxalic acid (poisonous) or use a cheap but effective alternative from the supermarket - Cillit Bang works, so does Harpic bathroom cleaner with limescale remover. I found that no amount of polishing worked - the brown stain soaks into the gel coat.
 
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