+x

 

Lester Populaire - 9/1/2019 4:21:00 PM

+x

 

Whitesol - 9/1/2019 7:55:17 AM

Hi,

I've recently come on to a problem  of which I'd like to know the exact cause, so what better place to ask than here..

I've skinned a few  plastic parts in CF  using the black basecoat & EL epoxy (fast hardener) and everything went as usual .. perfect

I applied an automotive UV resistant clearcoat (by spraygun) and the parts all looked stunning.

Now after a couple of days on the car, we're starting to see and feel  "ribbels" form  that run along exactly with the carbon fibre weave.
I've spoken to a few other people here that are into skinning and all have had the same problem with some parts but cannot explain the cause. They all say  that sanding & re-clearing the part solves the problem, but I'd like to know what causes it.

Some parts were installed on cars that were in the sun, others were  in a garage and have seen no sun .. yet both suffer the same issue

Probably just an issue with shrinking of the resin during polymerization. Make sure it is properly post cured so the glass transition temperature of the resin is higher than what the part will see during use. For automotive parts this can be really rather high...
Consult the technical data sheet of the resin to find curing cycles and the corresponding Tg.

+x

 

Whitesol - 9/2/2019 11:05:26 AM

+x

 

Lester Populaire - 9/1/2019 4:21:00 PM

+x

 

Whitesol - 9/1/2019 7:55:17 AM

Hi,

I've recently come on to a problem  of which I'd like to know the exact cause, so what better place to ask than here..

I've skinned a few  plastic parts in CF  using the black basecoat & EL epoxy (fast hardener) and everything went as usual .. perfect

I applied an automotive UV resistant clearcoat (by spraygun) and the parts all looked stunning.

Now after a couple of days on the car, we're starting to see and feel  "ribbels" form  that run along exactly with the carbon fibre weave.
I've spoken to a few other people here that are into skinning and all have had the same problem with some parts but cannot explain the cause. They all say  that sanding & re-clearing the part solves the problem, but I'd like to know what causes it.

Some parts were installed on cars that were in the sun, others were  in a garage and have seen no sun .. yet both suffer the same issue

Probably just an issue with shrinking of the resin during polymerization. Make sure it is properly post cured so the glass transition temperature of the resin is higher than what the part will see during use. For automotive parts this can be really rather high...
Consult the technical data sheet of the resin to find curing cycles and the corresponding Tg.

Thanks for your reply, but the part was not exposed to any heat during installation. It was installed on the doors of a garaged car, with the outside temp at max 25 degrees and no sunlight