Hull cleaning

MJWB

MJWB

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Evening folks
Starting to think ahead to hull cleaning, rubbing and waxing for the first time next year. Christmas is coming and it seems a good time to ask family for a few things in preparation. Never done it before so I'm after some advice.
1. I used a bit of Y10 in places last year but I've heard that people mix up their own homemade oxalic acid mixture using wallpaper paste. Does anyone have a recipe please? I'm concerned not to make it over concentrated.
2. Rubbing compound, any recommendations?
3. I've also been warned off using rubbing compound on old boats as by now the gelcoat might be very thin after years of rubbing compound treatment abuse. Mine is 31 years old and although in good nick, I tend to think that may be an indicator that former owners may well have gone at it with rubbing compound regularly. I can't see any points where I get a sense of the thickness remaining. Should I regard this as a possible risk?
4. What is a good wax to use for polish in a marine environment?
5. Lastly, any recommendations on a not too expensive variable speed buffing machine please?
Many thanks indeed.
 
Knowing what make of yacht would be helpful for the best advice. Do you know if your gel coat is brushed or sprayed, as this will also affect any advice.

If you have a Westerly, then my PowerPoint presntation of gel coat restoration will help. https://wiki.westerly-owners.co.uk/images/8/86/Gel_coat_renovation_19May2020.pdf It is still worth looking at but other makes do not have such thick gel coat as a Westerly. Since I made this presentation, I have sanded the hull again.

IMG_3133 1000pix.jpg
Concerto was launched in 1980, making her 41 years old. So you can make an old boat look good. The last time it took about 7 days to sand and compound the topsides.
 
I use oxcalic acid in hot water and add about the same again of cheap washing up liquid. I make mine up in peanut butter jars and one will do each side if hull.

Brush on all over, wait about 10 mins, wash with a bucket and sponge or a soft caravan brush, going over the whole lot and finally rinse off with clean water.

Then wash all over with wash n wax or some other car product which contains wax..

Works a treat and has brought a reasonable shine and finish to my hull which is 40 years old.
 
Concerto said:
Knowing what make of yacht would be helpful for the best advice. Do you know if your gel coat is brushed or sprayed, as this will also affect any advice.

If you have a Westerly, then my PowerPoint presntation of gel coat restoration will help. https://wiki.westerly-owners.co.uk/images/8/86/Gel_coat_renovation_19May2020.pdf It is still worth looking at but other makes do not have such thick gel coat as a Westerly. Since I made this presentation, I have sanded the hull again.

View attachment 125456
Concerto was launched in 1980, making her 41 years old. So you can make an old boat look good. The last time it took about 7 days to sand and compound the topsides.
Click to expand...

I have a Westerley Griffon from 1989. Brushed or sprayed gelcoat, I've no idea. Thanks re the presentation. I'll have a look.
 
MJWB said:
I have a Westerley Griffon from 1989. Brushed or sprayed gelcoat, I've no idea. Thanks re the presentation. I'll have a look.
Click to expand...
You are lucky as Westerly used a double brushed gel coat and you should have 2 to 3mm of gel coat. For the best finish I would wet sand the hull with 320 grit to remove the top layer as this will have gone a creamy colour as Westerly used a Ryland gel coat that is not UV stable. Sanding will only remove about 0.25mm, so there will be plenty of gel coat left. When you want to start, try doing just the transom from start to finish. Once finished you will have experience to try one topside before starting the other one. I forgot to mention that the gel coat should be protected with a UV polish. My local glassfibre repair guy recommended me to use Megulars Flagship polish and to use a mimum of 3 coats.
Meguiars Flagship Premium Marine Wax 473ml

IMG_2880 1000pix.jpg
This was taken on 31st August and shows the shine hull in daylight on Concerto's hull.
 
Concerto said:
You are lucky as Westerly used a double brushed gel coat and you should have 2 to 3mm of gel coat. For the best finish I would wet sand the hull with 320 grit to remove the top layer as this will have gone a creamy colour as Westerly used a Ryland gel coat that is not UV stable. Sanding will only remove about 0.25mm, so there will be plenty of gel coat left. When you want to start, try doing just the transom from start to finish. Once finished you will have experience to try one topside before starting the other one. I forgot to mention that the gel coat should be protected with a UV polish. My local glassfibre repair guy recommended me to use Megulars Flagship polish and to use a mimum of 3 coats.
Meguiars Flagship Premium Marine Wax 473ml

View attachment 125496
This was taken on 31st August and shows the shine hull in daylight on Concerto's hull.
Click to expand...

Many thanks for the detail, appreciated.
 
Graham376 said:
I dissolve around 100G of crystals in a litre of hot water for removing yellow at waterline but don't apply it hot. For hull cleaning, just supermarket cream cleaner on wet cloth, rinse off then polish by hand with Starbrite liquid polish with Teflon.
Click to expand...
Graham you may be right 100g is around 8 table spoons , I use three big tables spoon in a litre and that seems to do the job without any problem , try it next time and see what you think.
Why not hot ? i boil a kettle to is mine as a lot of my crystals are one big lump .
I find no sooner it's on the hot water works straight away .

We can't get wall paper paste so I use flour ,
Like your self I just use supermarket cream clearer Jif .
 
Like Pandos, I recommend using a saturated solution of oxalic acid prepared as described by others above. Then: empty half a bottle of Fairy liquid and fill it with the oxalic acid, mix, and you have a nice squirtable solution (best kept warm, if you can, so the acid does remains in solution). Squirt a bit of the green, gloopy liquid on the hull, and spread it thinly with a wet sponge. When you no longer see the pigment of the detergent (green?) it's enough. The acid works its "magic" only above a certain temperature (>10-15oC), so you better do this when it is warmish, or when the sun is shining on the hull.

The thickener of the Fairly Liquid is enough to keep the whole thing acting on the vertical sides. I prefer this to wall paper paste (messy, it is glue), or starch-based stuff (flour).

With regards to polishing, I woudl thoroughly recommend your potential Xmas buyers have a look at these kits:

AGlaze Marine Sealant – Marine AGlaze

Much better than wax (and much easier to apply).
 
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