Removing Waterline scale

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Simon 420

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We're new to boat ownership and in particular the delights of cleaning our boat in readiness for next season. I wonder if anyone has a tip for removing buildup of scale around the waterline please. Brick Acid, Cillit Bang and Spirits of Salt have been suggested by various passers-by watching us scrubbing away over the weekend, but I'm worrid that someof those may do harm to our gelcoat
Thanks
 
All of those will work, I have always used brick cleaner as it works out cheaper. Apply, leave for about 10 mins wash off
jobs a goodun.
Remember to use safety equipment for eyes and hands !
 
I use Cilit Lime and Rust Remover that you use for the bog ... rinse of after and polish up.

If you use it ... it does similar to Oxalic Acid ... you will find that you will do all hull side as that waterline will show up the rest !!

Cilit Bang is not as good as it used to be ... b****y greens have got at it and caused a change in composition ...

Good pair of rubber gloves of course
 
Oxalic Acid, cheap as chips on the internet, do the whole hull. Safety goggles and gloves are a must.
 
If you mean the brown stain just above waterline, many years ago Harpic toilet cleaner was recommended to me, it works a treat.
Apply neat on a rag, you think it's doing nothing then look back at that area 5 or 10 mins later and the stain has disappeared. Wash or hose off hull after you've been all around.
Anything containing oxalic acid as the working ingredient will do a job.
 
One of the problems with todays Toilet Cleaners ......... they've lost the active ingredient that made them so good. Even Cilit Lime and Rust Remover is not as good as it was ... due to those pesky Green People interfering with our chemicals !!

Any cleaner that has Phosphoric Acid or Oxalic Acid in does the job.

Here's a funny .... watch what Coca Cola does ... you'd be amazed. Or get a leaf stem from Rhubarb plant ... rub that on the stain ... that's Oxalic !
 
Once you've cleaned up .. then get polishing - because the surface now is like a magnet to all the crud imaginable.

The general advice is NOT to use T-Cut or car colour restorer - it can lead to 'yellowing' of surface. But I use it after CiLIt Lime and Rust Remover to get an overall evenness to the hull. Then I give a good power wash off after ... I used to get shampoo based car wash / polish ... but after finding my boat still goes 'green' over winter - just now use the L&R / T-Cut and that's it for the year.

For general clean-up in the summer ... Windex is quite good as it cuts some of the cr*p away ... good rinse off after ...

Pal of mine one year spent out on GRP Restorer - advertised as bringing back the shine to any old GRP ... it did but TBH - the price vs domestic products ?
 
John 32i said:
Y 10 cleaner - its a gel that you paint on, wait 10 mins and rinse off; easy!!
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There is some advantage in using a gel to improve coverage but Y10 works out expensive if you are treating anything but a small area. I use the similar Yachticon "anti-gilb" which comes in a handy bottle and is more liquid, making it easier to spread. A bottle lasts me several years for a 34ft boat.
 
I use Y10 which is brilliant, but expensive these days. Didn't know about the domestic alternatives however so will have a go when my currency container of Y10 is finished.

Incidentally someone mentioned that T-Cut isn't recommended as it can stain. That is correct in my experience, however I still use it but wash it off quickly and have not had any problems.

My bi-annual routine for the topsides is to Y10 the brown stuff, rinse that of, then a quick jet wash, then T-Cut with power polishing tool but not going too heavy on the bufffing, then wash thoroughly with soap and water to remove all T-Cut, then jetwash again. Finally when dry apply Autoglym Super Resin Polish and Autoglym Extra Gloss Protection. Done that for years and the GRP looks great and stays decent for a long time.
 
LadyInBed said:
Prep is a bit of a faff using oxalic acid and wallpaper paste, Y10 is about £11, Cillit Bang / Harpic about £1 or £2 and easily sourced.
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A better alternative than wall paper paste (which is actually a messy glue...) is Fairy Liquid. I do the following:

Raid your kitchen for a HALF USED bottle of Fairy Liquid. Add to it a concentrated solution of oxalic acid* (OA). Shake to make a nice green sloppy dense liquid. Squirt on topsides (use gloves and goggles, as others have said). Spread evenly with a sponge and let it act. OA needs relatively warm temps to work well. Rinse off. I find that the detergent in Fairy Liquid helps to get off the oily deposits and probably allows the OA to access the calcified deposits and act on them.

*this can easily be prepared by adding some hot water (200-300ml) to a few table spoons of OA, stirring and letting it cool down. Use the supernatant. The undissolved crystals can be used next time round. OA is pretty insoluble, so a tub of powder will last you an eternity. The real cost is the half bottle of Fairy Liquid (!)
 
Y10 is good and it does not break the bank if it last two years its less than two cup of coffee per year. It is temperature sensitive it does not work below 10 deg C and that is surface temp not air temp. That's not a sales gimmick I have tried it in the cold and nothing happens.
David MH
 
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