Prepping fiberglass parts

[Rick524]

I'm looking for advice on prepping the cowl and tail tips for paint. Is it a good
idea to scuff the gel coat with sandpaper so the paint sticks better? Does it need
primer before paint?
Thanks!

Rick
Sonex 524

[MichaelFarley56]

Hey Rick,

This is just my advice (I'm no expert!) so take it for what it's worth here...

Most certainly prep by sanding first. The paint needs some mechanical 'grip' to hold onto, and sanding works well. Before you do that however, make sure all fiberglass filling/smoothing/sanding work is done if you need to fix any blemishes.

Once that's done, sand as needed but I'd finish with maybe 320 grit, then use a tack cloth and wipe everything off well right before you spray paint. If you haven't done any fiberglass body work then I'd say primer is optional, but if you've used any filler you may want to prime over those areas.

Be sure to follow the paint manufacturer's advice on painting tips and conditions.

What products are you going to use to paint?

Good luck and use plenty of light!

[Rick524]

Thanks Mike. Not sure what I'm going to use for paint yet. Any suggestions?

Rick
Sonex 524

[fastj22]

You should clean the gel coat with a wax remover/degreaser before sanding. Then sand from 100 grit, then 220 then to 400 grit. Wet sand at 400 grit. Always use a block. Then wash raw gel coat/ fiberglass with dish soap and water. Fill any pinholes with glazing putty. Sand flush. Then prime. Next is a high build primer. Wet sand 400 after each coat and wash. The high build fills any small valleys. You sand off the peaks. Repeat until really smooth. Surface should really be smooth now with no visible scratches. When satisfied, then you can add color coats. Also, always wear nitrile gloves to keep the oil from your hands from contaminating the surface.

[Rick524]

Thanks for the detailed reply. Hopefully I'll be painting within a week
or two.

Rick
Sonex 524