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Join Date: Sep 2006
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FRP colour restoring

07/07/2007 4:18 AM


We have water slides , of FRP mould. The original colour was fully faded.

Can a FRP intricate mould , can be coated with any pigments /film , by which the colour can be restored. If possible ,how the life would be?

expecting eagerly for reply


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Join Date: Jun 2006
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Re: FRP colour restoring

07/07/2007 11:56 PM

The fibre in your structure is embedded. What people slide on is the colored gel coat. The dye/pigment was not made to resist sun. I cannot understand why this was done. The application was known to be in the bright summer sun and would have to be non fading. Possibly a cheaper fading pigment was used instead of the proper one?? Possibly you failed to specify the dye/pigment rigorously and the contractor chose the cheapest one, usually a fading one is cheaper.

Remedy:- You can clean and sand the surface and then paint it with a gel coat formulation of the right color and a sun proof pigment. Any area not cleaned and sanded to expose a good paintable surface will later delaminate. Suggest you try a few test spots first. The dye/pigments for sun proof use are well known and you should be able to find them out

Per Ardua Ad Astra
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Join Date: Mar 2007
Location: Devon England
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In reply to #1

Re: FRP colour restoring

07/08/2007 4:22 AM

We manufacture GRP - Glass Reinforced Plastic - boats - see - which clearly spend most of their time in the sun. We try to keep to white as that has very little sun fade from the UV effects.

Bright yellows are also good colours, but reds are very poor.

When we service an old competitors boat we often brighten the colour by polishing the surface with an electric polisher using Farecla G3 or G6 polishing compound used wet. This usually brings up a good bright colourful shine which we then coat with a few layers of 3M marine polish or the equivalent which you will be able to source from any good boat chandler.

This process usually lasts about a year before we repeat it for next season.

Try to avoid painting as it usually is a disappointment as the adhesion to the GRP is poor, so you end up with tiny splinters of paint as splinters for the children on the slides.

Hope this helps

Hugh Mattos Chartered Engineer...... :---------: Through helping others we give purpose to our time on this earth and take pleasure from it.
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Join Date: Mar 2007
Posts: 5

Re: FRP colour restoring

07/08/2007 1:39 PM

Can a FRP intricate mould , can be coated with any pigments /film , by which the colour can be restored. ..................No gel coat in FRP use is totally resistant to UV. UV inhibitors can be added to the coat to REDUCE the fading over a period of time. Please note: The inhibitors reduce but do not eliminate the fading under UV conditions. ..............Gel Coat can be thought of as a "plastic paint", not a paint to coat plastic but a paint that pigment content is made from plastic materials similar to the resins used to bond the fibers in the FRP. ..............Like all surfaces exposed to friction, (sliding) the paint (gel coat) thickness will decrease with time. Yes, the quality of the UV inhibitor used is important. More important is the quality and control of the resin. An example is E-Epoxy rather than Polyester. The dollars invested have a direct relationship to the life. ..............When we have a customer that has economic constraints on the project, the life expectation is explained for each approach that can increase cost and life and the customer will select the compromise that best suits the economic investment they envision. If this means that the gel coat thickness or that the UV inhibitors selected, reduce the appearance or wear resistance, then that is a compromise that is made based upon the constraints of the moment. ..............There are many ways to create a fresh appearance. With FRP, as mentioned in a previous post on this topic, the surface prep is vital. Until recently, the methods for revitalization have been restricted to cosmetic layers being applied on top of the existing gel coat. NOTE: A thin gel coat will fade more quickly than a coat applied in the original process a few mill's thicker, even with the same UV inhibitor. As with the existing UV and wear resistance, there needs to be recognition that there is also a maximum life expectancy to the cosmetic repair. ..............It can be expected that (like rubbing two painted pencils together) that the coating will not only wear, but will lack the same ratio of elasticity as the original gel coat and will eventually flake. In the case of water park slides, it's why "mats" have become popular to sit on while sliding. It reduces friction as well as the transfer of splinters or splinter flakes. ..............Over the last two years, a proprietary system has become available that consists of two parts. The first part softens the pigment particles within the original gel coat. You can feel this take place as it becomes soft, can be indented by pressure from a fingernail or even scratched. During this process the Pigment elements are, for lack of a better description, floated to the top but uniform throughout the thin layer of plastic gel coat. The area of preparation has to be restricted to the amount of area that can be sealed without the area drying. .............Then the second process of applying a (again for lack of a better term) "sealant" is undertaken. While the second step contains additional UV inhibitors, it is absorbed into the soft pigment below the surface. As soon as the pigment particles begin to absorb the material, you will see a shine begin to appear as each microscopic pigment particle absorbs the "sealer". What is taking place is that many elements of the pigment density to shine that are lost to UV exposure are being added back to the pigment. It's important to not apply more than floats the pigment. If too much is applied or if it is applied when the pigment has hardened, it become no more than a "clear coat" layer to wear off. ..............The preparation material is applied by hand and the second step is applied by spray. Spray is most effective since you are (if done correctly) applying the second step to a softened pigment. You can do it by hand but you run the risk of wiping away or displacing the pigment from the friction and pressure that hand application creates. ...............This restores the original shine and luster IN DIRECT RELATIONSHIP TO THE AMOUNT OF PIGMENT REMAINING BELOW THE SURFACE THAT HAS FADED. The life expectancy can be similar, but still less than the original finish IF and only IF you are restoring a surface that has faded and not worn away. ...............The process is non-toxic and requires no investment in protective or environmental controls. ................The process isn't to be confused with the consumer products available to rub, wax or polish. The normal consumer product removes the pores in the surface and is sealed to create a gloss. Much like the boat polishing discussed earlier. ...............The products to accomplish this softening of the pigment (on any surface that is coated with a pigment material) are not normally available in small quantities for a boat or a car. While a 55-gallon drum can be repackaged into smaller containers, it takes a lot of small container sales to not distract from the core use in large commercial applications. ................The cost per gallon at first appears high, but then the coverage is rather significant. When all is said and done, it is most simply stated as "the recycling of the remains of the original pigments". ................Since it's not practical to remove all the pigment (gel coat or paint); Place it in a bucket and mix it up with a reactive chemical to create fresh pigment, it is and in-situ process. It's very fast and it's very effective. AGAIN: As in all things, it has to be done right or it will not exceed your expectations. ................For those of us that with deal high tech Carbon Fiber, fiber class and FRP's of all kinds, this process is a welcome unique technology. It isn't on the radar of the consumer mainstream since buffing of a car or boat is a profit center. But then there is a point where the buffing process eventually takes away depth rather than restore pigment qualities lost to UV exposure. .................One final note: RED contains more pigment to create color than other colors. Ever notice how coatings, even red plastic for injection molding, are more expensive? RED can be one of the worst choices for a plastic or plastic paint for UV resistance as well as economics. When it does fade, it's loss of pigment as a percentage of thickness is greater because there is more pigment. As the previous post suggested: RED is more difficult to restore and care for. ...................I know that this was long winded and tremendously over simplified in chemical detail. But, in part, that is what this board is about. Sharing options with others that have the need for a solution rather than an R&D product. The owner of a boat manufacturing or an amusement park don't need to gain an advanced degree in chemical engineering that is out of date the day they receive it. I really hope this helps. I can be contacted via my mailbox for this forum if there is a serious interest in the product referenced. From that contact, I can share with you the vendor for the chemicals involved. From that point you are on your own. Two things I try to avoid: 1) I may elect to not pass onto vendors of products referenced any inquiries that lack the value the vendor seeks. It makes a manufacturer or vendor less receptive to me in the future. 2) Each of us has knowledge limited to education and more importantly: Experiences in life. That is the limits of the knowledge I share. I avoid engaging in debate within a forum. Dennis The ultimate level of genius is creating understanding to an 8 year old. Anything else may still be genius, but not at the ultimate level.

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Anonymous Poster

Re: FRP colour restoring

07/09/2007 9:37 AM

I would suggest restoring colour with a fluorinated urethane finish that is resistant to water and sun.

Check with

Although not on their website, they manufacture an immersion fluorinated urethane that should last many years.

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