Laser hull discolouration
Printed From: Yachts and Yachting Online
Category: General
Forum Name: Repair & maintenance
Forum Discription: Questions & tips on the subject
URL: http://www.yachtsandyachting.com/forum/forum_posts.asp?TID=11753
Printed Date: 13 May 25 at 7:13pm
Software Version: Web Wiz Forums 9.665y - http://www.webwizforums.com
Topic: Laser hull discolouration
Posted By: StevieDexter
Subject: Laser hull discolouration
Date Posted: 11 Nov 14 at 7:48pm
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Hi I've bought a second hand Laser and the previous owner had some horrible 'ANIMAL' brand decals on the bow. I've carefully removed these but where they have been on there for so long they have bleached the hull and left a nasty off white version of the decal design. What steps can I take to try and get rid of these? Can it be cleaned or will I have to re-coat the whole hull? Thanks in advance Steve
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Replies:
Posted By: Rupert
Date Posted: 11 Nov 14 at 9:18pm
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Have you tried rubbing compounds? T Cut, maybe, though I'm sure someone can remember a brand more suited to GRP. Faracla make some, I know.
------------- Firefly 2324, Puffin 229, Minisail 3446 Mirror 70686 |
Posted By: StevieDexter
Date Posted: 11 Nov 14 at 9:37pm
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Thanks Rupert No I haven't. After I posted this I read something about using 600 wet and dry to rub it down but not sure what I'd finish the job with after that. Maybe T Cut...
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Posted By: JimC
Date Posted: 11 Nov 14 at 11:52pm
| I'd start with the T cut and avoid the wet and dry unless totally desperate. |
Posted By: kneewrecker
Date Posted: 12 Nov 14 at 9:05am
| failing that, just put a bigger sticker over it of a brand you like. |
Posted By: StevieDexter
Date Posted: 12 Nov 14 at 6:05pm
 It was a big decal!!!!
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Posted By: jeffers
Date Posted: 13 Nov 14 at 4:45pm
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When i cleaned my Laser hull up prior to selling it I gave it an all over t-cut (to get rid of the brown 'tide mark' that the hulls seem to develop). Took me a couple of hours all told but the boat looked very shiny and the new owner was impressed when he looked round it. I would avoid wet and dry, this is just too abrasive IMO unless you are trying to get rid of scratches.
------------- Paul ---------------------- D-Zero GBR 74 |
Posted By: piglet
Date Posted: 13 Nov 14 at 8:42pm
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Try T-cut first, but the abrasive in T-cut is very fine and may not dig deep enough to remove the discoloured surface layer. Next step would be to get your hands on some Farecla G3 or 3m perfect-it 09374. Wet & dry would cut the surface off but 600 is very fierce, 2000 or 1200 at the most, use wet on a soft block (eg. polystyrene) and don't waste time with knackered paper, it's a consumeable! |
Posted By: Medway Maniac
Date Posted: 13 Nov 14 at 11:51pm
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I was told by one who claimed to know, that if you waxed your hull with silicone car wax, it wouldn't fade. Tried it on my blue above the waterline L3k and it didn't fade, but it might not have anyway. Can anyone conform or deny? ------------- http://www.wilsoniansc.org.uk" rel="nofollow - Wilsonian SC http://www.3000class.org.uk" rel="nofollow - 3000 Class |
Posted By: JimC
Date Posted: 14 Nov 14 at 12:29am
| I believe there are car waxes that have a UV filtering capability, and that ought to reduce fading. |
Posted By: Null
Date Posted: 14 Nov 14 at 7:23am
Exactly this, don't be too scared to use wet and dry. But not 600 grit. I would start around 1200 moving to super fine in small steps. Then finish with facela compound and an electric mop (a proper one not a Mickey mouse fag lighter powered one)
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Posted By: StevieDexter
Date Posted: 14 Nov 14 at 10:00am
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Thanks for the tips! I will try with T-Cut first I think and see how that goes. If I remember I'll take some photos. |
Posted By: piglet
Date Posted: 14 Nov 14 at 11:19am
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I put uv protection waxes in the same category as magic beans.
However, the more light you can reflect back the less your gelcoat will have to absorb.
The 2000 owners at my club have all bought top covers with extended sides to cover the blue.
There are dozens of expensive products out there:
http://www.3mdirect.co.uk/boat-wax-3m-scotchgard-marine-protective-liquid-wax-09061-1-x-500mm-1.html" rel="nofollow - http://www.3mdirect.co.uk/boat-wax-3m-scotchgard-marine-protective-liquid-wax-09061-1-x-500mm-1.html
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Posted By: piglet
Date Posted: 14 Nov 14 at 11:20am
| You can compound without a polisher, but you might get tennis elbow in the process. |
Posted By: Rupert
Date Posted: 14 Nov 14 at 12:14pm
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Many of the polishers say "do not use with rubbing compounds" or the like on them. The one I use does, and never had a problem. I think you have to be careful that you don't "burn" the surface by rubbing and rubbing in one place till there is no compound left.
------------- Firefly 2324, Puffin 229, Minisail 3446 Mirror 70686 |
Posted By: Null
Date Posted: 14 Nov 14 at 12:42pm
| Car body shop Mops are best, but like Rupert says you need to be really careful not to burnn through the gel. Make sure the pad is always moist by using a water spray. They are very expensive to buy so renting one with a sponge head is probably the best option. I would also be carfeul on classes with thing gel. The laser is prime for a MOP! |
Posted By: JimC
Date Posted: 14 Nov 14 at 1:46pm
| the other thing to beware of is exactly what's going on: is it that the gel coat has gone pale where the sticker was, or darkened where it wasn't? If the latter should be the case then you could end up removing a lot of gel coat to no advantage. |
Posted By: piglet
Date Posted: 14 Nov 14 at 1:49pm
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We use Farecla sponge heads on Draper 6" air grinders here, have tried lambs wool but too fussy and the edges can damage.
As Null said, keep it damp, a few sprinkles from the w&d bucket does the trick.
You do have to try quite hard to burn gelcoat with a mop, car paint is more delicate.
This is all very well if one is in the trade but a lot of trouble & expense for someone who just wants to tidy his boat up.
Anyone got any inside knowledge of Vela grey?
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Posted By: deadrock
Date Posted: 14 Nov 14 at 6:27pm
| Laser gelcoat is only about 1mm thick in places, especially the bottom areas that get the scratches. At Draycote in the late 1970s one sailor used T-Cut and a rotary buffer, and had managed to produce the perfect shine. Until he stood back and saw a large dark patch: he'd gone completely through the gelcoat. |
Posted By: Rupert
Date Posted: 14 Nov 14 at 8:06pm
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The gel coat on my Lightning is so old and has been smoothed so many times (some by me, many before, I think, and worn by trolleys) that it is see through in many places. Soon I'll have to paint her. Hewever, I think it would take a while (and serious lack of care) to wear out unsanded Laser gel coat. Imm is actually quite think in this situation.
------------- Firefly 2324, Puffin 229, Minisail 3446 Mirror 70686 |
Posted By: Paramedic
Date Posted: 16 Nov 14 at 9:07am
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There is loads of gelcoat on a laser hull compared with most classes today, though it would have been rather thin by 70's standards. If you are careful you can sand out most abrasions with 600-800 them finish with 1200 before polishing. This will be much faster than just polishing it off, with the tradeoff that you do need to take more care. Provided you are careful you will remove no more gel than the polish only method as all you want to do is remove the discolouration. Obviously you could hit problems if this has been done before, so on an old boat i would check carefully before proceeding. If you shine a torch directly onto the hull in a garage or shelter you will be able to see very fine sanding marks that polish does not quite remove. You do need to get the light just right for this, but they look very different to scratches due to use and are a dead giveaway that someone has had a go before. The discolouration is more than likely due to UV, though i have seen a couple of boats that have changed colour due to damp being held behind something stuck to the boat. These have always been dark colours and you have to wait a few weeks/months for the gel to breathe the moisture out. This is also more likely where a chart has been taped on rather than a sticker which is adhesive. One boat with this problem returned to its original colour over the summer.
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Posted By: piglet
Date Posted: 16 Nov 14 at 7:27pm
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"very fine sanding marks that polish does not quite remove."
Not on my watch! |
Posted By: Paramedic
Date Posted: 17 Nov 14 at 8:04am
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haha, if you've had go at yours i bet i can find some ;) ------------- |
Posted By: piglet
Date Posted: 17 Nov 14 at 11:59am
| Thank you Paramedic, I have my FAW certificate but that doesn't make me good at your job! |
Posted By: Paramedic
Date Posted: 17 Nov 14 at 2:57pm
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I do apologise, I totally forgot that it's a requirement round here that you have your sense of humour removed before posting. Have a nice day :) ------------- |
Posted By: BoatShowAvenue
Date Posted: 11 Dec 14 at 10:12pm
This is a big piece of advice, the wet and dry technique should be your last resource.
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