Hi everyone!

As a product designer, I have always been interested in building with carbon fiber. I recently purchased a 3D printer and me and my friend came up with the idea to print molds and use them to make carbon fiber parts. We came up with the idea to make a cruiser skateboard using hand lay-up and vacuumbagging. (Similar to this video: https://www.youtube.com/watch?v=scvXKij1hQ0) 
A cruiser rides like a longboard. But in contrast to longboards, skateboard cruisers are shorter and more maneuverable. There are usually made out of plastic and very flexibel which provides an easy and surfy ride.


Since this is the first time we try this, I prefer some feedback on what we have planned. I still have some open questions. Please let me know if you have any comments, tips & tricks or links to usefull literature or videos. Anything is welcome!
I have the following in mind:

1. Mold making
I use my Prusa i3 MK3S to make a mold out of PLA filament. The mold will be printed in 3-4 pieces because the printbed is not big enough. I will glue/bolt the pieces together and use a filler and sanding-paper to make the inside smooth. (any recommendation for the filler?)

2. Reinforcement
I would like the board to have a nice flexibility to it. You should be able to jump on the board with your full weight and nearly hit the ground. Also bend it pretty hard in sharp turns which results in high torsional forces. There are a lot of parameters which can influence the flexibility. I hope you can help me choosing the right epoxy and reinforcement layers to help me in the right direction. After that I can still play with other parameters like the thickness of the foam inlay or adding ribs on the bottom to fine-tune the flexibility. 

I did some research and came up with the following lay-up:

1st layer  - 210g 2x2 Twill 3k Carbon Fibre
2nd layer - 300g /- 45 Biaxial 3k Carbon Fibre
3rd layer - Foam inlay 
4th layer - 300g /- 45 Biaxial 3k Carbon Fibre
5th layer - 210g 2x2 Twill 3k Carbon Fibre

I was planning to add unidirectional fiber in the length of the board between layer 1&2 + 4&5 but I'm afraid the board will get too stiff, any suggestions?

3. Epoxy
I'm not sure which epoxy I should choose. EL2 Epoxy Laminating Resin or XCR Epoxy Coating Resin? Which one would be more preferable to achieve the flexibility I want. 

4. Vacuumbagging
I'm planning to use the Vacuum Bagging Starter Kit provided by Easycomposites

Please let me know what you think!

Kind regards