To Paint a Fiberglass Car

Shocks, Springs, Brakes, Frame, Body Work, etc

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chimpvalet
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Re: To Paint a Fiberglass Car

Post by chimpvalet »

Thanks for the replies. With respect to media blasting I am wary of going at the body with this approach for several reasons. First, both those with whom I have spoken on their experience with this and those who have posted online reports have found that even soda blasting left much filling and leveling work to be done afterwards. Reports on the use of chemical strippers were even worse. The OEM paint on this car, though crazed lightly in many horizontal areas due, presumably, to thermal stress from sunlight is otherwise quite tough and tenacious. I have so far stuck with manual sanding and am finding it takes plenty of time to remove the topcoat, even using 80 wet. Once through that though it is quite a bit easier to cut down through the primer/filler and gelcoats and I wonder if this difference in removal rates would complicate the work of a blaster in that same way. Sure it's tempting to take any easier path through this but it seems I might be working up a better surface profile while I am blocking my way through to the gel coat. If that turns out to be true then perhaps less time and effort are wasted by the manual work than would appear to be the case at first glance. I'll make an effort to take the back end ( taillamp ) panel through to near paint-worthiness and report further once that's done.
Cheers,
Steve
chimpvalet
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Re: To Paint a Fiberglass Car

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I've decided to go with walnut shell blasting. With a lot of work still ahead in the resto, it's time I kick-started the process with some outside help. Took one headlight pod to the recommended local guy and he produced a nice result in about 5 minutes time. Inside surfaces brought back to as when removed from the mould, outside surfaces brought down to first layer of primer left with a texture like leather. Looks like light scuffing will still be required before priming but I can see that through. Hard to work areas like the forward and aft bays, plus wheelwells will be just about ready to paint on return. Flat sanding will follow priming, of course, but that will wait 'til all the components, cables and lines have been trial fitted and removed as I want to minimize the time spent knocking around a finished car. Thanks for all the great advice.
chimpvalet
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Re: To Paint a Fiberglass Car

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Now have the body back in hand from the blaster with photos to share on the outcome. In words, what I now have is a shell with some measure of primer remaining on most of the high finish surfaces, clean gelcoat in places like the wheelwells, clean 'glass in areas left rough at the time of production. The way forward will be to first block out the residual primer smooth to 150 grit before filling countless pinholes with 2K. Final smoothing with 240 dry should put me in position to take the car to the painter. Looks like walnut shell was a good choice, sparing me lots of clean-up work in wheelwells and engine bay, and getting past the tough OEM finish on the rest of the car. As to the pinholes, it's reported that soda blasting the same car type gave the same result, FWIW. Thanks to all again for guidance in this.
Steve
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Bob Hollinshead
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Re: To Paint a Fiberglass Car

Post by Bob Hollinshead »

Good quality epoxy primer on glass for the best durability and lifespan, polyester primer and fillers can be applied over the epoxy for blocking, then finish up with epoxy and final sanding before sealer and paint. SPI epoxy gets my vote for the best quality.
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chimpvalet
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Re: To Paint a Fiberglass Car

Post by chimpvalet »

Aaah, thanks Bob. I wasn't thinking of priming ahead of the filling and blocking but it makes sense to get the best base before going on, if I understand the situation. So because there is a fair bit of residual primer left in many areas I figure it will be OK to block that down overall ahead of the epoxy, agree?
Regards
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