fibreglass basics

[DarrenH]

i get the resin, hardner, matting bit. my question is, if i wanted to form a grp object around an existing painted metal object, how would i go about it (other than buying gel coat separately, and making a mould)

the object in question is underbonnet strengthener which is detached from the bonnet skin.

to oversimplify things, could i apply something to the metal that grp resin will not stick to (cellophane, polythene sheet) let it harden, pop it out, peel the sheet off, then dress and trim ??

many thanks

[Tathan]

Yes. You can get proper release wax that'll let them separate. I've never made anything big or complicated but it didn't seem that hard tbh.

[alistairolsen]

Either polish it till its mega shiney and apply mold release wax to it, or use PVA based release agent, or if the finish doesnt matter too much (it will be the underside of a grp bonnet) cover it carefully in sellotape and then polish it and it will release fine.

WARNING: Use Sellotape, not any of the cheap impersonations!

[DarrenH]

nice one thanks for the info. yeah the finish doesnt matter

[gixerboyuk]

I made some bits for my kit car and used kitchen foil to stop it bonding to the buck i had made

[BlackBox]

I used PVA to make my lotus 7 panel copies, worked fine and you only need a weak mix. Get it from the builders outlets as it's cheap .... spray it on the panel to be fiberglassed.

[DarrenH]

excellent lots of ideas. cling film, pva, sellotape. bit of a theme going there

[Tathan]

yeah, i used to love blue peter

[Brian_S]

Stick some photos up Daz when you do it!

[djivesp]

foil works, but it rips up into a gazillion pieces when you release it and it's a nut-ache! half my bootlid still crunches with foil every time i open/close it lmao! Release wax works and is best where surface finish is top priority but you need so many friggin layers of it, it's expensive and takes forever to do.
I'd also recommend PVA a gazilion times over anything else especially if it doesn't have to be surface-perfect . Pops out then you just wash it off! You can get a good surface with it, but if it's curved, pva does tend to sag and collect up in the crevices, getting thicker in those areas.

[Briggz]

there is a good series of videos on youtube about fibreglassing, they also have a website which sell all the stuff you need,