Pocket Board (HF) Layup Question

[hcohen2018]

Hi Guys,

Been reading allot here and learning so much so thank you all for posting.
I'm planning to build a Hydrofoil Pocket board and was wondering if the layup I came up with is good for a budget-lightweight-strong board. I don't have vacuum so everything will be laid by hand, from what I understood, there is no point for carbon if I'm not using vacuum.

Layup from deck to bottom
4oz glass
4oz glass
g10 epoxy plate 2mm 20x30cm in the mast holes connection to distribute load
Core - Pink construction XPS, I just got those for free from my work.
g10 plate 2mm again
4oz glass
4oz glass

The planned size is 100x48x3
I'm a big guy at 1.83cm and 100kg

Maybe add a strip of additional glass along the board?
If the layup strong enough?
I saw the idea of combining g10 plates into the foam core in a DIY video online. Should I go with 3mm, 4mm there?


Thanks for helping out.

[TomW]

No. On xps you need 3x 6oz glass on bottom and top .Add a 4th foot patch on top.
Xps is extremely soft. It's still probably going to heel dent

Your mast attachment must have solid plugs of epoxy or plastic all the way through.

[Pierrot]

I’m not an expert but seems too light.
I’m currently building another pocket and I have 2x6oz of carbon and 6oz of glass on each side + a strip of 12oz carbon on the length of the board
+ wood stringers

[tmcfarla]

On mine I did 2 layers of 6 oz carbon fiber on each side along with 2 strips of unidirectional carbon (maybe 25x80 cm), and that is over a heavy foam. The board is probably overbuilt, but it is still very light. I wouldn’t skimp too much on material, it really doesn’t seem to add much weight to make it bomb-proof.

[thewindego]

I would be skeptical about the xps holding up for long...delamination.

Is anybody having good luck with it long term?

I am doing full corecell M80 cores now. My 109x45x2 naked carbon is 2.1kg and its bomber with 19oz carbon skins plus uni.

[TomW]

Yes, you will need carbon stringers each side, like 600g uni D each side, 150wide.

You should to get some 10-15 mm 80-50kg/m3 foam and glue together over simple rocker form

[rynhardt]

I would be skeptical about the xps holding up for long...delamination.

Is anybody having good luck with it long term?

I am doing full corecell M80 cores now. My 109x45x2 naked carbon is 2.1kg and its bomber with 19oz carbon skins plus uni.

I love the corecell M80. Such a nice foam!

[thewindego]

Yes it really works well with typical wood tools router etc. Not inexpensive but totally worth it IMO. No water absorption and excellent mechanical parameters make it a winner. It is readily available here too but only in full sheet.

[hcohen2018]

Thank you all for the great tips.

So 3x6oz it is from each side + mast attachments patches.


more questions:
1. rocker - what is the best way to achieve using foam core? glue pieces together? bend thicker piece?
2. is the g10 plate going to help? its a soild 2mm epoxy plate which i plan to put one on top and one bottom at the mast area. should I skip it?
3. My foil plate is meant for rail setup, how do you recommend going about it? should I tap the holes in the plate making it for screw connection?


the xps I have is of quality type which meant as an isolate for construction, so minimal water absorption


Thanks you all

[Breze]

This was my method of building a XPS Foilboard. Still going strong.
viewtopic.php?t=2400849
Now, if making a new one, i would buy 2 sheets 10mm Airex and epoxy them together on the rockertable.
Now that i know my mast- feet position i would go for a simple and light 4 hole M8 V4 nuts fixation