Most GRP products come with a nice and smooth gel coat for the visible side, however many still have a rough 'hidden' side.

The first example that springs to mind is the rear of GRP seats...

Can a gel-coat be retrospectively applied to these rough surfaces, or is there a better method for getting a well-finished surface?

Ta!

Was wandering the same thing about the inside of my car. I was considering trying a skim of filler, a bit of sanding, followed by a spray matte black.

Jek

That was another option I had considered, but I reckoned the filler would probably crack over time and fall out... ???

Gel coat needs an oxygen free environment to set, you'ld want to use flowcoat. But yes, fundamentally you could yes. It would make the item obviously a fair bit heavier, but you can.

Thanks Ben!

if they are going to be painted afterwards, a little coloidal silica as a filler mixed into either resin or gelcoat with help. CS comes from any resin supplier, East Coast fibreglass etc.
Resin/CS mix is structural whereas flowcoat isnt really.

key the seat back first, 60grit or similar and then wipe over with acetone and allow to dry before adding resin or flowcoat.

ordinary car body filler is best avoided as it will crack in time especially on seats which flex constantly.

filler and fibreglass mix....

i hear that works.

You can get a thick gel coat and add some liquid wax instead of using flow coat. It does the same thing.

you can use glecoat and then sand back, its only the surface that doesnt cure

Cheers people!

dont cover the back of your seats! you'll miss all the prickly fun when you are fitting your harnesses...

add resin/gel coat in 50/50 measures , you can use coloroued gel coat , its thinner and flows better than flowcoat .

As used in lightweight darrians.....