it is not really any different to painting metal
Key the surface of the fibreglass panels, use p600 wet and dry until you have no shiny surface left.
Clean the panel down with panel wipe, or similar
Then paint with etch primer
The secret to painting is patience. Don't try to cover the area in one coat. Spray on several light coats, perhaps six or more, to build up a drip free primer coat that completely covers the old surface. Follow the directions on the paint can, especially those about shaking and mixing the paint before and during use.
If you do get runs dont worry too much, leave it overnight to dry and then lightly sand them out with
p600 and use soapy water on the surface (stops the paper clogging)
You don't have to allow each coat to dry completely. You can recoat the primer as soon as the previous coat become tacky. If you spray light coats, you can recoat in ten minutes. After about an hour of this, you should have the primer coat done. It should completely cover all the surface, and it should have a uniform appearance.
This is when you find out how well your filling and sanding really worked. Any little imperfection in the surface will now be very visible. Now wait 24 hours for the primer to dry.
Give it a quick sand back with the 600 paper and lots of soapy water (washing up liquid is fine for this)
After that prime it using the same technique as above and a quick sand when it is all done
then clean the surface down and your ready for paint.
For metallics use similar technique as above for painting (just light coats) you dont want to get runs in it.
then clear laquer, keep the first 2 coats light as if they run it will show inthe metallic particles.
these 2 coats will seal the paint, then the subsequent coats you can apply the laquer a bit heavier so you just start to see a little bit of reflection in it.
Once you have several coats on it, leave it a week to dry, you can then flat it down (look at my guide for getting the shine on your paint) and polish
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