restoring white gelcoat - any tips?

[julians]

Hi all,

My boat is 9 years old now, and while in generally pretty good condition, some of the gelcoat has started to turn slightly yellow ,presumably from exposure to the sun.

It seems to be mostly the gelcoat in the cockpit on horizontal surfaces under the glass screen, ie those areas that are angled to catch the sun the most, and are not protected from the sun even when the cockpit cover is on. I noticed the yellowing when the compass failed, I removed it to fit a new one, and realised how the area under the compass was the original white colour, and the area around it has started to yellow.

Are there any products out there that will restore it to its original colour?

I had tried some polish on a small area, but it didnt make any noticeable difference.

 

[cliffdale]

chine shine. Google it. I have used it and it works as in the video, amazing st

 

[gjgm]

I'd try any compounding product- slightly stronger than polish, and then polish it. Most of the marine cleaning,wax etc brand names will make something a little more agressive.

 

[julians]

cliffdale - I thought chineshine was only good for restoring whiteness where the yellowing was caused by growth/staining from water etc, if its good at sorting out yellowing from exposure to the sun I will give it a go. Now I just need to find a supplier of it in mallorca, it looks a bit too risky to take it out in hold baggage.

GJGM - yep maybe a stronger compounding product is the answer - will try the chineshine, and if thats no good then then I will resort to elbow grease

 

[Bandit]

What is the boat ( manufacturer).

 

[julians]

Its a windy 25

 

[CX54WEK]

If all else fails you can flat the gelcoat back with some fine paper and then polish it back up.

 

[P4Paul]

cliffdale - I thought chineshine was only good for restoring whiteness where the yellowing was caused by growth/staining from water etc

What you describe will not be fixed by chine shine which is great at removing discolouration caused by something growing on the hull.

You need to remove the top surface of the discoloured gel to expose the original colour. Compound will do this but depending on the manufacturer and the amount of light and heat exposure you may find that the discolouration is deeper than initially thought and quite possibly not uniform across large surfaces.

Be mindful that unless you have room to compound back the entire area or feather out the edges, you could end up with a surface looking worse that you started.

 

[P4Paul]

If all else fails you can flat the gelcoat back with some fine paper and then polish it back up.

Yep, you can run over with a block and 2000 grit with plenty of water and soap and as you say, the OP will still need to compound/polish before waxing. Being in in the eye-line and under the glass, if the OP just runs over it with paper it will look terrible in the late afternoon/evening sunlight

 

[julians]

Be mindful that unless you have room to compound back the entire area or feather out the edges, you could end up with a surface looking worse that you started.

yep, thanks, that thought had occured to me also. I will have to check I can get at all areas, dont want to make it worse.

I will have to do it by hand (not by machine), as the access is too tight for a polishing machine, is it generally possible to do a good enough job by hand?

 

[Bandit]

Its a windy 25

About that time there was a problem with mould release agents on other manufacture of boats about that time causing a yellowing which looks like a water stain, I don't think its that.

I would try a marine rubbing compound by hand on a small area first.

Do You have a tonneau cover that comes over the screen. This may reduce the discolouration but if you don't have one already try the rubbing compound and a good polish if it works well.

 

[julians]

About that time there was a problem with mould release agents on other manufacture of boats about that time causing a yellowing which looks like a water stain, I don't think its that.

I would try a marine rubbing compound by hand on a small area first.

Do You have a tonneau cover that comes over the screen. This may reduce the discolouration but if you don't have one already try the rubbing compound and a good polish if it works well.

Thanks, I dont think its the first problem you describe.

I have a tonneau, but the studs it hooks over are round the stainless windscreen rail, so it doesnt cover the glass. I have started laying towels over the exposed areas of fibreglass in the cockpit to minimise the effects of the sun.

I will get some rubbing compound and go from there.

 

[julians]

so now, what rubbing compund to use?

This 3m stuff

http://www.ebay.co.uk/itm/3M-Marine...er-/301807420670?_trksid=p2141725.m3641.l6368

claims to do both the compounding and the polishing in one, is this sort of stuff worthwhile, or should I get a seperate compound and polish?

 

[gjgm]

so now, what rubbing compund to use?

This 3m stuff

http://www.ebay.co.uk/itm/3M-Marine...er-/301807420670?_trksid=p2141725.m3641.l6368

claims to do both the compounding and the polishing in one, is this sort of stuff worthwhile, or should I get a seperate compound and polish?

I had this on the Khamsin; it wasnt difficult to address, but I would start light and work to more coarse if really needed, so def. do not start with even 2000 grit paper. No need for the 2 in 1 product, though that is usually what they seem to market. Obviously work over a wide area so you don't get a line between cleaned and uncleaned, but it was 15 minute job and was fine by hand.

 

[P4Paul]

so now, what rubbing compund to use?

This 3m stuff

http://www.ebay.co.uk/itm/3M-Marine...er-/301807420670?_trksid=p2141725.m3641.l6368

claims to do both the compounding and the polishing in one, is this sort of stuff worthwhile, or should I get a seperate compound and polish?

Personally I would never buy this kind of product from Ebay or Amazon as they are not always what they seem! It looks like the one you linked is in the US style bottle.