I'm moulding a helmet so i can produce more of them, I've got my silicone ready to go, but I'm having a hard time finding fibreglass cloth and resin. Do any UK anons know where I can buy any (Thats not too expensive), do any other anons have any alternatives to fibreglass? I have heard that Plaster of Paris works, but I'm not very experienced with this sort of thing.
seconding east coast fibreglass. reblended polyester resin and chop strand mat is cheap if you don't need lloyds approval.
silicone moulding is a last ditch thing you'd pull out for shapes that don't have a split line. are you following a guide from a movie prop shop?
I *reeeeaaaally* hope you're just making costume helmets here....
>bondo isn't a common thing here in the UK,
Bondo (a name-brand) isn't sold at "hardware" stores: it is used as a cheap and easy (tho not very durable) way of filling in minor car body damage. It is a one-part resin that already has some kind of chopped-fiber filler added. It's sold at auto parts stores, or at some department stores that have automotive sections.
The best selections and prices for composite supplies are probably online.
If you want somewhere local to get some fiberglass / epoxy fast, then shops that do boat repairs will have some on hand but they may not have it in retail packaging because they mainly buy it to use themselves.
You can use either epoxy (50/50 mix) or polyester resin (resin is about 90%, and you add ~10% hardener to it). I find the epoxy easier to mix but both can work perfect. And both are a fuming toxic mess until cured, don't breath it or get any on your skin. And both are kinda expensive.
Your first attempt will look like crap. The 3rd or 4th attempt will look a lot better.
Im going to make a silicone mould of the helmet, then use fibreglass around it to make sure it keeps it's shape when im casting with it. I dont care about the look of the fibreglass, but thanks for sharing