Need Advice on Restoring Old and Beat Up FRP Chassis

[Mechanic AH 581]

I have a late 80s buggy kit I'm restoring (bought the kit used). It's quite beat up but I want to use the '80s black FRP chassis because it's still seems solid. Has anyone tried to restore a beat up FRP/composite chassis from that period and the results were satisfactory? Anyone have pictures and any advice?

I'm also trying to figure what kind of black matte spray paint would be best--something that can take a little beating and doesn't easily scuff, mark, or peel. Any suggestions there?

My process would be to wash it first maybe with some composite/plastic safe degreaser, then mild detergent/water. Sand some areas of the chassis, recondition the edges, prime/paint matte black, spray a matte varnish for protection. I'm debating if I even want to use filler/putty.

Oh and the previous owner used CA glue to mount a backbone to the chassis and left some residue so I'll be using a CA debonder for that.

Anyone with some experience/advice? Thanks.

[Collin 1956]

If you paint it plack it does not look like FRP anymore, so why?

 

Wash it, sand it, fill it, sand it, spray it.

 

[ACCEL 2014]

Now, if it were me?................................................................

keeping the original because it's original? That's good.

better would be trace and lay out CF if possible.................. If it were me,

i'd be doing both just to do it.

 

[Mechanic AH 581]

@Collin I understand. Just not sure what people have been doing. I feel if I don't paint it, it will just look the same/scratched up and if I sand and don't paint it, it will looked damaged.

@ACCEL If only I could work with CF. Unfortunately, I don't have the tools or proper work space. But I guess I can still try working on the original chassis, and if I'm not satisfied, just try to be patient while looking for reasonably priced replacement parts. Thanks both!

[t3garett 268]

I have done this before and polished the frp as best I could with automotive 3m cut polish. Then varnished it. Problem is when the original layer of varnish/epoxy has come off and your left with bare fiber then you have to re varnish it.    

[Collin 1956]

I would get some Epoxy in the spray (clear one), it is usually clear and used as a primer. Some thin layers added and it might be fine. Restaurations are always a bit of tinkering to make things look nice but still working. As @t3garett mentioned, with polishing or sanding you will loose to first layer of epoxy and the fabrique comes through.

[Mechanic AH 581]

@t3garett @Collin Thanks for the advice and suggestions. I can try and test a small area too. I assume any varnish, spray, paint, or epoxy will also come off at some point. If I get it to a point where it looks decent enough, I still won't push the car as much until I can find a replacement FRP chassis. Thanks again :)!

[Collin 1956]

Epoxy spray will not get off the FRP, Epoxy is made to produce FRP. Also I forgot to mention you can paint the scratches with UV resistent marker befor coating with clear epoxy.

 

[Nicadraus 6201]

Aside from clear epoxy, you can use clear urethane paint with catalyst mix. It'll harden like resin once cured. It'll be good for FRP and carbon fiber restoration or sealing fresh fiber. I would go that route if I were you. If done properly, finish would look great too. 

You also need urethane acrylic thinner to mix with that. 

[Collin 1956]

20 hours ago, Nicadraus said:

Aside from clear epoxy, you can use clear urethane paint with catalyst mix. It'll harden like resin once cured. It'll be good for FRP and carbon fiber restoration or sealing fresh fiber. I would go that route if I were you. If done properly, finish would look great too. 

You also need urethane acrylic thinner to mix with that. 

Would be too messy for me. Also you need only a very tiny bit of colour and after you have two open cans of paint and hardener. KISS (keep it save and simple). But definitly it would work.

[Nicadraus 6201]

1 hour ago, Collin said:

Would be too messy for me. Also you need only a very tiny bit of colour and after you have two open cans of paint and hardener. KISS (keep it save and simple). But definitly it would work.

Why would it be too messy? I use urethane paints all the time in my models, RC, turntables and car works all the time. I'd only get small amounts if I needed too. Besides it does the job quickly and neatly.

KISS (Keep it smooth and sauve). Hahaha!

[Collin 1956]

On 11/7/2020 at 6:52 PM, Mechanic AH said:

I have a late 80s buggy kit I'm restoring...

6 hours ago, Nicadraus said:

I use urethane paints all the time in my models, RC, turntables and car works all the time.

Can you see the difference? But does not matter, your way is brilliant, no doubt.

[TurnipJF 9192]

I tend to take the easy way out and send the part (or its measurements) off to Hansell Composites (www.fibre-lyte.co.uk) for them to duplicate on their CNC machines. That way you can keep your original with its authentic patina, and have a reliable supply of expertly-produced spares in fibreglass or carbon. Their prices are pretty good too - in many cases cheaper than buying the materials and equipment to do it yourself.

[Mechanic AH 581]

@TurnipJF thanks for the tip! I’ll keep that in mind. Maybe for an alloy part.