How hard is fibreglassing?

[VinceFox]

Ok, let me give some context here...

I want to make some specific airbox covers for a bike. I can sculpt the shape out of foam, wed clay or whatever else is needed, but if i do, how difficult is it to then make fibreglass side panels? Is it possible to get a finish good enough to hold up to high build primer and flat black paint?

[DrDeAtH]

You need to make a mould of the part. Then make your part inside the mould.
Me thinks you need to buy a book.....

[VinceFox]

What's best to make the moud from? Do i make that from fibreglass as well then put some sort of barrier inside it?

I'm pretty handy at most stuff, just never really tried fibre-ing and i've got to the stage with my cafe project that woud be really useful if i could make some simple custom panels.

[ch427]

fibreglassing isnt difficult just messy, i cant see you getting a decent finish unless you do a skim coat of filler on them which would probably look crap.
Gel coat is the usual finish to apply but ive only ever done repairs not full gel application.

[paintman]

Make the mould from grp. Plenty of release agent on the part you're using as the pattern then brush on mixed resin (or ideally gelcoat) & let it go off. Apply a couple of layers of chopped strand mat with resin & let the whole lot go off.
Remove the mould former (your pattern) from the mould. Deal with any surface defects.
Plenty of release agent on it.
Ideally apply gelcoat (plenty on ebay & not expensive), but I've done it before with mixed resin exactly as per making the mould. Depending how thick you want it you then build up with layers of mat - CSM will do or woven cloth, I've used both on bikes & boats. Be sure to stipple down with a brush or use a roller to ensure its thoroughly wetted with resin & all air is removed.

This on youtube (lots more there too):
http://www.youtube.com/watch?v=BOo8gxp3K3w

Edited by paintman on Sunday 30th December 12:12