Thanks for your answers. My question is if it is really necessary to use time consuming techniques? I mean, can I vacuum bag a laminate like this at a time?  [epoxy resin as "gel coat" + wet carbon fibre with epoxy resin + PU foam 4 mm + wet carbon fibre with epoxy resin]. I'm afraid thet the air don't "travel" across de foam core, or may be iti is not strictly necessary if first plies are well wetted...Thanks!

3Dcore gives added strength over std foam too.

As FLD  says you could lay-up one or two layers first and then add the core. Remember for a core to be effective is must be backed up with more layers of reinforcement so that you have a sandwich, ie 2 layers of reinforcement - Core - 2 layers of reinforcement. The core is only there to separate the reinforcement. The greater the distance between the reinforcement the stiffer/stronger the panel will be, because the fibres have to stretch further for a given deflection.

If I'm foam coring a moulding I lay up one skin with a layer of peel ply and bag that.  I then bond in the core and add the second skin.  Its a bit time consuming but is reliable in its results.

Hello everybody!

I have a question for you experts. I would like to know if do I have to take into consideration some special points before vacuum bagging a sandwich laminate with PU foam. Do I have to make holes in the foam necessarily? I'm afraid the air don't go up from the first skin and have bubbles on my laminate. Of course, I would paint the mould before with clear epoxy resin.

Is it a good idea to use Soric for vacuum bagging? as it is designed for infusion or RTM.....Thanks and have a nice and productive weekend!