Mold making

[MDP]

I have a 48" model boat(powered by a weedeater) hull (Scarab style) I would like to make a mold of to reproduce the model. I have worked with FRP before. What do I use as a releasing agent to separate the plug from the mold? I have heard that vacuum bagging is the best way to form the FRP can this be done by a backyard builder?

Thanks
Mike

[SamSam]

http://boatdesign.net/forums/showthr...070#post131070

[Splint]

Hi Mike,
yes infusion can be done by a back yard builder but if you must I would do quiet a few practice runs on smaller parts and see how you go with that before taking on a part the size of a hull. Things can go wrong, such as running out of resin and sucking air inot the mold part way through infusion, punctures in the bag causing the styreen to boil off possibly resulting in a failed part, insufficient vacuum to pull the resin past the next row of resin supply ports. Also the risk of things like loss of vacuum part way through infusion etc.
The main advantage of infusion is to acheive a low resin to glass ratio in the part which results in a lighter more robust part. If you were planning on doing production building I would certainly reccomend taking up vacuum infusion but in a one off situation with little or no prior infusion experience I would reccomend a hand layup.

Cheers
Splint