polishing topsides

saab96 said:
I've never had to do this on ferro or steel boats but my painted GRP hull looks tatty. Question: why do people leave polish on their topsides on for months so that it forms a white powder coating? If it makes the job easier I'm up for it.
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I must admit I never heard of that one. Since the polishing compound requires friction to work and it’s made in a paste so it does not fly away as dust. I even fail to see how that can work. Are you sure you’re not referring to the chalkiness of the GRP itself when left unpolished and waxed?
 
GregOddity said:
I must admit I never heard of that one. Since the polishing compound requires friction to work and it’s made in a paste so it does not fly away as dust. I even fail to see how that can work. Are you sure you’re not referring to the chalkiness of the GRP itself when left unpolished and waxed?
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I've been in a couple of yards this last week where people pay to have their boats polished and noticed white swirl marks over the whole topsides just like polish has been put on and then not cleaned off. So it isn't the GRP but something put on it, like a car wax would look if you put it on and left it. These boats have been left for months so I assume its deliberate and that it's been left like that by the yard, since their workers (not the owner DIY) put the polish on in the first place. Is the dried paste protecting the GRP from sun/UV? I'm in the tropics at the moment but I saw this in equally sunny southern Portugal earlier this year (again, where owners pay the yards to polish their boats and most boats get seriously polished). I'm never likely to pay a yard to polish a boat but I would like to pick up tips that are not objective rather than sales pitch.
 
saab96 said:
I've been in a couple of yards this last week where people pay to have their boats polished and noticed white swirl marks over the whole topsides just like polish has been put on and then not cleaned off. So it isn't the GRP but something put on it, like a car wax would look if you put it on and left it. These boats have been left for months so I assume its deliberate and that it's been left like that by the yard, since their workers (not the owner DIY) put the polish on in the first place. Is the dried paste protecting the GRP from sun/UV? I'm in the tropics at the moment but I saw this in equally sunny southern Portugal earlier this year (again, where owners pay the yards to polish their boats and most boats get seriously polished). I'm never likely to pay a yard to polish a boat but I would like to pick up tips that are not objective rather than sales pitch.
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In Portugal boats do have to be thoroughly polished and waxed to avoid UV damage to the GRP. The Polish itself does not protect the GRP, but the wax is used as a sacrificial barrier against the damage from the GRP. It is common to use quite a lot of wax to protect against the damage of UV. I am by no means a specialist on the subject and my knowledge is from what I’ve seen done, what I was told by people that do it professionally and by what I have read. I personally never seen leaving the swirls, but I have seen 4 and 6 coats of wax given by an owner.

Mine in the UK I gave 3 coats not long ago, after polishing with high grade paste, finer polish and then a finishing polish compound. But this is on Selkie and she’s only 22”, on Oddity that is 33 I’m already dreading it and the boat is not even finished.

To start I use a few jet washes to get it really soaked and as clean as possible, then I use Harpic concentrated gel for toilets diluted at one to one that I spray on the boat. You can top that with a patio cleaner acid after the first treatment with Harpic to get a really shiny white boat. Harpic I leave on for 15 to 20m then a thorough rinse. With the acid and Harpic you must watch all acrylics. It can affect the antifoul as it runs of so I would do it before new antifoul.

The only tip I can give you, is how to polish any moulded antiskid, which is better done with a hard polishing wheel for stainless mounted on an electric drill (the hard ones have bristles between the layers of cotton) or wherever you can use it with. I used a softer finishing cotton wheel for the wax. LOW RPM’s and NEVER staying in one place or you will leave a burn mark on the GRP skin, always a circular motion. You can sand any burn marks you create (ask me how I know) away with 1000 sandpaper but you’re back to polishing from start with cutting paste then the medium grade and polish.


I’m sure someone on the forum will be able to tell you better then I can the best way to protect it. I’m still “learning” GRP boats as well ?
 
Graham376 said:
That's news to me but I've only had the boat here for 12 years. Never see any different polishing techniques or polishes to those in UK.
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UVR Radiation is much stronger in there then in the UK. Some plastics just start crumbling after only a few years. Today the phenomena are better understood and it does not happen so often but in the 90's the rage was changing "plastic" windows sold in the late 80's that were literally crumbling away.
I personally never seen leaving wax accumulation on anything. But I'm used to at least 3 coats of wax on everything that needs UV protection. Here in the UK, my neighbours do a 1 coat of wax type of thing and most thought it was funny that I was doing 3.
 
Have you considered simply cleaning the topsides and applying one of these wet-look floor finishes such as Zep? I tried it recently and the results were impressive although how it will last in the long term I can't say but it's a lot quicker and easier than polishing.
 
This is how we did Selkie. Last year in June we took the boat out of the water. Selkie had been abandoned in the pontoon for several years and had scratches from the pontoon on her side and was yellow all over. We cleaned her with Harpic twice after a good few washes and a bit of scraping then we did not have time to polish her.

This time as we raised her out of the water the chalkiness of the hull had again started to turn yellow and even inside the cockpit and decks. We again washed her copiously and then gave her the Harpic treatment once again. At this stage is about just cleaning as best you can before you start polish as you do not want to smear any residues into the gel coat as you polish.
We did it in sections of around 30 cm on the hull and used masking tape to help marking the areas we were polishing. For the wax, we spread the wax all over one side at a time and then polished the wax at a LOW speed. Then next etc. you get the point.

On the pics you can see the progression and the state she was in when we begun with a very opaque white with no reflections and leaving a white dust on your fingers.

Kinda hard to get good pics of the polish with cloudy weather but you can see the the end result on the last 2 pics.

PS.- the pics were for the wife so you get to see my ugly mug :p

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Early in my boat-owning career I read somewhere that it was a good idea to put polish on in the autumn but leave it without buffing it off. When the spring came it was a nightmare to remove, and I suspect that modern preparations and waxes are just as bad.
 
Spent some money and got myself a good buffing machine , full topsides 600 grit wet then 800 then 1000,
then 2 x polish 1000 grade then to fine polish, then full wax 1 x coat then buff.
this was a hard graft , but the hull was in bad shape, took it from a stained oxidation yellow effect, to were you could see your face in the shine in a 35 year old hull.
Its all in the prep and the products you use and the effort put on
good luck
 
Be very wary if tempted to use an oxalic acid hull cleaner ( most of the stuff on chandlery shelves is oxalic, check ).

I'm repeating what I said earlier on another thread but I think this is important.

For a start, in the name of all that's holy use good eye protection, goggles not glasses.

I used this stuff on my boat years ago; as the instructions say ' to neutralise rinse with water ' I foolishly thought it must be feeble stuff.

When it came to washing the topsides down the residue ran down my arms; they started to tingle, very quickly followed by burning - I knew I was in trouble and legged it for the club loos.

Running a cold tap over my arms didn't stop it, by then I was in agony; luckily a member who used to be a hospital matron had noticedmy plight and knew what to do, had me fill a basin with cold water and keep my arms immersed for 40 minutes minimum.

I cringe when I think I wasn't using eye protection, I'm certain if I'd got it in my eyes I'd have been blinded.

So if using this stuff be careful, also of anyone passing by.
 
johnalison said:
Early in my boat-owning career I read somewhere that it was a good idea to put polish on in the autumn but leave it without buffing it off. When the spring came it was a nightmare to remove, and I suspect that modern preparations and waxes are just as bad.
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When I spoke to a professional team working on a boat in the yard a couple of years ago, about doing mine, they said that ideally they would like to do the hard work in the Autumn, leave the wax applied but unpolished and come back just before launch to polish, so it is still a technique that some pros use.

In the end I did it myself and there is an element of satisfaction in transforming dull topsides into shiny ones, but unfortunately it doesn’t last.
 
Tomaret said:
When I spoke to a professional team working on a boat in the yard a couple of years ago, about doing mine, they said that ideally they would like to do the hard work in the Autumn, leave the wax applied but unpolished and come back just before launch to polish, so it is still a technique that some pros use.
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They probably only do it that way so that the boat looks clean and shiny at launch, when the owner will notice and be happy to pay their bill. I've always found it much easier to polish the wax off almost immediately.

Tomaret said:
In the end I did it myself and there is an element of satisfaction in transforming dull topsides into shiny ones, but unfortunately it doesn’t last.
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What doesn't last, the satisfaction or the shine?:rolleyes:
 
GregOddity said:
Here in the UK, my neighbours do a 1 coat of wax type of thing and most thought it was funny that I was doing 3.
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I also think it's strange and unnecessary. Mine (in Algarve UV) gets an annual quick wipe with Cif cream cleaner and then a coat of liquid Starbrite with teflon. No chalkiness and no gel degradation after 12 years here, boat's now 30 years old. If it needed 3 coats of wax on white hull, I would be worried about the quality of gel used.
 
pvb said:
They probably only do it that way so that the boat looks clean and shiny at launch, when the owner will notice and be happy to pay their bill. I've always found it much easier to polish the wax off almost immediately.



What doesn't last, the satisfaction or the shine?:rolleyes:
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The shine goes first, then the satisfaction.

I do like the boat to look good when she’s launched, but once I’m sailing again what the topsides looks like to others is not a concern to me.
 
Tomaret said:
The shine goes first, then the satisfaction.

I do like the boat to look good when she’s launched, but once I’m sailing again what the topsides looks like to others is not a concern to me.
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I only lift the boat for antifouling and polishing once every 2 years, so I'm fairly keen to use decent stuff. My favourite is Meguiars - a couple of coats of polish, followed by a couple of coats of wax. It's very easy to apply and rub off by hand, and seems to last well.
 
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