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Old 20th March 2012, 05:47 AM
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Wynand Wynand is offline
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Join Date: Nov 2010
Location: South Africa
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Quote:
Originally Posted by robo View Post
I dont think there is a problem with fade. There are three westies running around here which are immaculate, one of them is a dark blue and its got to be 15 years old if its a day as its got an escort axle in the back. All of them still in the gelcoat and no fade. I have seen red bleach before but that was yonks ago and even that polished up ok. They might have escaped it because they are garaged!
Bob
Keeping it out of the sun did help in a big way and perhaps the fibreglass man got things right when making them....
Quote:
My friend Luke has ordered a fibre glass kit frm NTS Engineering but without a finished gel coat finish.
I think it still has a gelcoat, albeit a clear one applied to have the smooth mold finish, read below.

I work with GRP basically on a daily basis and for years had built boats and other fibre stuff for a living and am on record many times for my mistrust in gelcoat.
I would venture and say as much as 90% of all gelcoats applied to molds are much to thick according to specs and herein lies its danger. Styrene get trapped in the molding because of that and over years (especially when exposed to sun like boats) would surface through the gelcoat hence the fading / discolouring and a common symptom is cracking of the gelcoat and usually starts as little hairline spider web like crack. In severe cases the gelcoat just open up in cracks.

The reason many apply the gelcoat thickly is to get coverage to prevent brush streaks especially with "difficult" colours like red for instance. The best way to apply gelcoat is to spray it on evenly and the equipment for that is very expensive and I would venture and say that no manufacturer doing seven body moldings have this type of equipment.

The reason why gelcoat has to be applied to the mold is to get a smooth surface - laminating directly against a mold result in many small pin holes because of resin not fully saturated through the CSM and is very difficult to repair because of its small size.
The way I did my car's body moldings was to use white gelcoat very sparsely (streaky see through) and just enough to get a smooth surface finish from the mold. These parts were later lightly dry sanded down with aluminum oxide sanding sheets (360#) and two pack epoxy primer and top coats paints applied.

All good two pack epoxy paints are far superior than gelcoats and will outlast it and you obtain a better finish with deep colours if you applied a few coats of colour top coat and optional clear coat applied if you want to go that way. And you can basically have any colour you wish for...
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Wynand
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Last edited by Wynand : 20th March 2012 at 05:57 AM. Reason: typo
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