Paint suitable for fibreglass

Paint suitable for fibreglass

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Astacus

Original Poster:

3,485 posts

241 months

Saturday 30th December 2017
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I am dealing with lots of cracks at the moment. Grinding out, tissuing and sanding back. Some of the areas its very hard to tell whether I have got a good surface and I'd like to get a rattle can and spray a coat over the general area to check. Does anyone have experience of this. Can you recommend a suitable paint that won't be a problem to the sprayer, if there are any remnants left behind?

Dollyman1850

6,319 posts

257 months

Saturday 30th December 2017
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Don't.

Carefully grind back. you can check surface by shining a bright light from behind.
Best to go back 3 x size of repair and laminate in 3 stages overlapping small to larger with the 3rd coat where you laminate just shy of the hole you have gouged. you should use acetone to get rid of contamination and use resin and matting with a final resin and tissue. personally I like white colour resin which makes repairs stand out from the substrate.. Don't contaminate repaired areas with paint until you are ready to filler prime surface.

Before paint if you have done a good job of the matting work you can use 3M Reface which can be sprayed or brushed on and this is a good product for finishing prior to filler priming.

https://www.spraygunsdirect.co.uk/index.php/paint-...

N.

Astacus

Original Poster:

3,485 posts

241 months

Saturday 30th December 2017
quotequote all
Thanks Neil, thats what I am doing with the damaged areas, except in some it really does look like only one layer of lay-up was originally used. Round the filler for example and along the rear deck its really thin.

Thanks for the pointer for the primer, ill give that a look.

Edited by Astacus on Sunday 31st December 14:13

Andrew Gray

4,969 posts

156 months

Sunday 31st December 2017
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plasticpig72

1,647 posts

156 months

Sunday 31st December 2017
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I always use acetone also but only to clean or degrease then it evapourates away quickly.
Never to leave things in soak.
Alan

phillpot

17,279 posts

190 months

Sunday 31st December 2017
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Andrew Gray said:
Acetone Why Neil
I buy all my fibreglass requirements from Polyfibre, thease guys know their business "inside out" and are happy to give advice.

One of the things they stressed to me was any repair must be spotless before laying on new matting and resin, don't think any sanding dust will be soaked into the resin and not a problem. How do you acheive this? Wipe everything down with Acetone. smile

Astacus

Original Poster:

3,485 posts

241 months

Sunday 31st December 2017
quotequote all
Yes I always use acetone to clean up the area before I repair it. You would be amazed at the amount of crap that comes off. Also, The original lay-up wasn't always great. There are quite a lot of small voids that have collected muck over the years and end up as black dots that have to be removed.

I always find it best to do the initial dressing of the repair when it is still slightly green, then you can shape quickly with a surform without making a load of dust, then quickly finish off with 60grit before working up the grades to about 240 after it has gone off properly. I have found some pretty hideous previous repairs where glass has been laid up over what looks like a mat black paint in the wheel arches. That lot just peeled right off. Another part where a repair had been made between the rear deck and the wheel arch, just laid on top of the shiny "gelcoat". That also just pealed straight off.

plasticpig72

1,647 posts

156 months

Monday 1st January 2018
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Some times if it is a convex shape and you don't want it to be sticky with styrene when hard. You can put some cling film over the resin so there is no contact with the air. When you remove the cling film it will not be sticky.
I always finish with resin and tissue like Neil and try not to use filler.
Alan

Astacus

Original Poster:

3,485 posts

241 months

Monday 1st January 2018
quotequote all
plasticpig72 said:
Some times if it is a convex shape and you don't want it to be sticky with styrene when hard. You can put some cling film over the resin so there is no contact with the air. When you remove the cling film it will not be sticky.
I always finish with resin and tissue like Neil and try not to use filler.
Alan
Nice idea, I had never thought of that. I certainly agree with the no filler idea. So the polymerisation is inhibited by the air and leaves the styrene surface sticky? I had aways wondered why the surface took so long to go off, when the remains in the pot were solid!

Edited by Astacus on Monday 1st January 13:19