10 replies to this topic

[Horace]

Can someone explain to me what the difference is in the painting process for GRP vs metal.

 

Is the gel coat just a different way of saying the lacquer?

 

I'm looking around for a decent paintshop, and I want to ask them if they have any experience of painting GRP and sound like I know what I'm talking about.

[christhegasman]

No gel coat how I understand is part of the fibre glass preparation which makes it fairly smooth And is below primer paint and lacquer

[fezzasus]

As above.

 

Gel coat is the first layer you put down when molding fibreglass parts, it creates a smooth surface which needs minimal prep.

 

Note; the automatic process that lotus used for the VX220 parts doesn't have a get coat. They inject a slurry of resin and strand into moulds, then release slightly as they cure to let the resin flow to the surface to smooth. 

 

Main differences between painting fibreglass and metal:

 

a ) don't want to bake at too high a temperature

b ) some primers might react with fibreglass. Ideally use polyester primer.

Edited by fezzasus, 07 April 2016 - 11:43 AM.

[Horace]

So to repair and paint my stone chipped front end, the body shop must:

 

1. Sand down and remove old flaky paint

2. Fibreglass repair any dents, dings, holes

3.  Apply a gel coat

4. Apply a polyester primer

5. Apply new blue paint

6. Apply lacquer

 

Have I got it right?

Edited by Horace, 07 April 2016 - 12:25 PM.

[techieboy]

No, no gel coat required. The resin and/or filler they use on the repairs should be sufficient for sanding/priming/painting.

[slindborg]

Gel coat has a habbit of not curing properly if its left to the air (as in it needs ramming into a mold iirc)

[fezzasus]

No, no gel coat required. The resin and/or filler they use on the repairs should be sufficient for sanding/priming/painting.

 

This.

 

There's no gel coat on the original bodywork, and gel coat doesn't cure properly in air so no point applying. Just grind out, perform any figerglass repairs, fill and prime with polyester.

[Horace]

Thanks guys.

[Horace]

So basically, it's the same as doing a fibreglass repair on a metal car, then spraying it

[fezzasus]

Yes.

[christhegasman]

Unles you stone chips are actually blisters which is a different story that someone will clear up for me