Blue hull bug bear !

[normskib]

What is it with Dark Blue Hulls on the Thames? Before I put my boat in the river I polished it with a top of the range wax product , but for some reason every time I look at the hull it's covered in what I can only describe as a white residue ! That's almost impossible to remove!!! And believe me I've tried everything including various products including star brite hull cleaner and various other products that say they do the job but don't even non marine products like viakal,handy andy etc I fact the only product that makes any kind of impression on what looks like limescale is a full scale limescale remover which I'm sure using would be a disaster for the river environment , but even using that its not long before the problem returns Any tips would be more than appreciated.(we're all doomed I tell ya )

 

[byron]

Blue Hulls always look so cool but all suffer that powdery look after a while. I haven't a clue what causes it, maybe it's a colour reaction to sunlight.

 

[boatone]

Its not limescale but deterioration (fading) of the colour pigments that make it blue. - and there's nothing you can do to stop it. Polishing, or wiping with any oily substance (even water) seems to offer brief relief but the fact is the coating - be it gelcoat or paint - is b*gg*r*d.

Even Byrons skippers cap - which used to be a real dark navy blue has become a muddy shade of brown - same applies to a certain lockie's shorts!

On my last boat I had the blue section round the gunwale wrapped with vinyl and I know some people that have had the whole hull wrapped. Time will tell how long it stays looking good.

 

[Alpha22]

There are two possibilities... one is limescale and this is most likely in your case as it removes with limescale remover.

The other is faded, chalky GRP, which will polish up.

I used to get it lots on my blue hull. Mr Muscle "Lime and Grime" did a reasonable job.

 

[JorgeinLondon]

On my last boat I had the blue section round the gunwale wrapped with vinyl and I know some people that have had the whole hull wrapped. Time will tell how long it stays looking good.

I'm thinking about a Vinyl wrap. What was the process like? What about pricing in relation to a paint job?

 

[Flynnbarr]

Blue hulls are extremely hard work to keep looking good.
Have read that the only thing that a boat owner does once is blue hulls and or teak decks

The white residue is lime scale,white vinegar,lemon juice or Viakal etc will get it off.You have to leave it on for a bit for it to do its thing and keep going over it as it naturally wants to run off the hull.Use the spray trigger bottles.Then rinse and dry using a window squeegee.I don't think any of it is good for the river,they are all acids,but I'm no chemist.
I feel your pain,you learn to live with it otherwise you end up being a slave to your hull,white ones have it but it doesn't show.

 

[miket]

We had a blue hulled Nimbus 345 that looked gorgeous, but swore never again!
2 boats on we have a blue hulled Broom 38!!
They are relatively hard work if you want them to look good. A bit like a black car?!

The white chalky deposits only appear if you don't look after the boat or your mooring is very exposed to sunlight. Med' boats suffer badly. It all cleans up beautifully and once done properly will last with no more effort than a white hull that is well maintained. When we first bought this boat it was not great. 2 days later it looked like new. I used Farecla G3 (cutting compound) with a damp cloth, followed by Farecla G3 (cleaner), followed by Blue T-cut (adds depth to colour), Autoglym Super Resin Polish (wax) and if you want it all to last longer I finish with Autoglym Extra Gloss Protection. All applied and removed with a cloth. I am sure that a machine would be easier, but beware of creating "circles"!
I polish the boat in March before it goes back into the water and by the end of October, when it comes out for the winter it still looks good.

The white spots are calcium deposits. You don't get them on the coast with salt water. They come off very easily with "patio cleaner". This is acid (hydroclauric?). When the boat comes out of the water, I wipe over small areas (6 ft lengths of hull) with a 50/50 water/acid solution. Leave for a few minutes only and rinse off thoroughly with fresh water. I do not bother mid-season. Once finished I use a window cleaning blade to remove the surplus water. One of those Karcher vacuum blades would be better still. By the time completed, most people think I have polished the boat again.

I rarely have to polish mid season except the rear buttreses that do go dull mid season. they buff up easily with Blue T-cut and Super Resin Polish.

Would I buy another blue hulled boat? I probably would not intend to, but could easily be swayed back to it. They look so much better!

 

[Marine Reflections]

There are a few reasons for this, without pics it could be either one.

Oxidation - the oxidising of the gel coat, which would give a bloomy look to the surface and would be in relation to sun exposure, mainly due to not having the surface protected off from oxygen via a wax.

Calcium deposits from the water, usually from tap water that has not been treated / filtered when rinsing, or not being dried before the sun dries the droplets on the surface. The sun dries the water and leaves the calcium deposit on the surface.

When removing the deposits you have to make sure they have not been waxed or sealed over in the past, or you will be only cleaning the surface of the protectant and not the old calcium deposits. So a wipe with acetone (if GRP) or IPA (if paint) will de-grease old protection and open things up for de-scaling.

If that works for you consider buying a water filter that filters out all the calcium deposits etc to rinse down after a wash. Drying off a hull is one of the hardest jobs to do and in some scenarios just isn't possible.

A water filter will solve this particular issue , certainly in the hot weather where the water dries 30 seconds after you have rinsed.

 

[Wavey]

Here's a case in point. Broom 42 cl's like mine are very sought after just now but this one will take a significant knock on price and/or put a lot of potential buyers off unless the owner does something about the hull. The picture was taken immediately after washing but you can already see the state of the hull towards the stern where it's started to dry. When fully dry it looks pretty awful. Shame but for the want of a bit of time/effort/money.

 

[Marine Reflections]

Was at a boat show one year and client asked if I could just give the hull a quick wash before the start of the show.

The hull was dark blue on a steel boat and it had been baking in the sun for a few hours.

My answer was simple, it's too hot to clean at the moment. It will just make a mess.

Client had never heard of anything so silly, "I've been doing this for years and have never heard of not being able to clean the hull in the sun" he said.

"no problem" I said, "If you can place your hand on the surface and keep it there for five seconds I will wash the hull for you and I won't even charge."

I think he liked a challenge, but had never really thought how hot the hull gets at times, places hand on surface. - Starts counting, 1......... sssssshhhhhhhhhh arrrrgggghhhhhh!

I'll do it in later on tonight shall I?