Resin discolored from the sun?

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#1

Hello to all!

Recently I started refinishing a friends spoiler from a 2003 Lancer Evo 8. Ive gotten all of the clear coat removed and its down to the fabric almost. The thing ive noticed is the discoloration in certain areas. Where in some areas its lighter and others its darker.

Here are some pictures to give a better idea:

This is the before. Uv damaged pretty bad.


Here you can see the transition in colors…


So you can see it better I did a little test strip of clear coat.


and here is a closer angle.

My question is this even fixable? I honestley dont see adding resin as a resolve. Perhaps a trasparent pigment?

Any thoughts please feel free to let me know. Ive never done a refurbish before so this is a bit of a learning curve!

#2

I think you can’t change that, may be you can place the part without clearcoat in the sun so that all the resin will get the same colour. But that will take time.
You can try to heat the spoiler, could be humidity in the resin, than it becomes white.

#3

You could try sanding it down to the carbon. Its going to be very risky but stop as soon as the black dust appears. The degradded epoxy will still be impregnated in the fabric and theres nothing you can do about it. Then cover it with epoxy and protect from UV with a decent clear coat.

#4

I am not certain this is UV damage. It might also be either slightly more sanding into the fiber, or air voids which somehow show more now.

Try talking him into a painted spoiler, perhaps with some carbon “flashes” over it.

#5

I’ve tackled this before and the only thing I came up with was to spray it with a black candy, then clearcoat. It won’t fix it perfectly, but the candy is translucent and does a pretty good job of covering the discoloration. Not perfect by any means, but better than anything else I could come up with.

Here’s what I used:
http://alsacorp.com/products/candyconcentrates/candy.htm

#6

If you want to keep the look, you could do a thin overlay.

Looking at the second picture, the cloud pattern looks like what you see with thermoplastic injected parts where re-grind was added to the hopper without mixing with virgin pellets. If it was infused, I would guess at an inconsistent matrix mix.

#7

Those were my thoughts exactly.

#8

I haven’t thought about that. But if I had sanded more so in that area to cause the discoloration then why does it still show in the area where there is the yellowing above it?

Also if I were to start sanding into the fabric what grit would you recommend?

With the sandpaper I would assume that I would sand the darker areas until they become gray and uniform?

Herman, what are carbon fiber flashes?

#9

Flashes: most of the part in colour, with some strips / flashes / some kinky graphic, perhaps a tribal, in carbon. Design such that the bad parts are hidden.