flow media and bridging

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#1

I have a a few questions regarding flow media. i have a small petrol cap mould and i am having problems with bridging. but is not the bag which i first thought.

my pleats are ample so my question is do i have to put flow media over the full surface. i am going to be cutting it in peices and putting more than one single peice and probably doing the same with peel ply,

also can i ask how many people spray epoxy gel coat onto there moulds because i am bit wary of using spraying 3m glue onto the surface of the mould as would like a perfect sureface

and if you do spray the epoxy in how long before it goes off??

regards

#2

second thoughts school boy error i know epoxies shouldnt be sprayed. :s

#3

If you part is small enough you may be able to use no flow media, that would solve that problem. If you must use, cut it in the corners. Also during vacuum down the bag use a rubber tool to push in the corners. Just because you have pleats in your bag it doesnt mean youll have no bridging of materials, slow controlled vacuum works well.

#4

Yer i have gatherd this i thought on one of my first attempts it was a bag too tight? But i know 100 percent its not. I sloly pull vacuum and rubb in with a lolly stick and releasle then pull an keep working it down.

I think im going tl cut mesh slight smaller than the panel and place it in the flat area of the feul cap. Then place strips down the sides and along the front where the reson inlet will be for distribution. Im learning every day i just find i wanna pack it all in when bits go wrong there is soo much to learn