Hi all,

Just got back from a great week of surfing on a vanguard style sup I built a couple of years ago and am starting to plan a new build. I just wanted to float some ideas around and se if anyone thinks this is either a good or bad idea and maybe work through a few problems.

So anyway after reading mountains of stuff on swaylocks here etc I can't stop thinking about building a board using the lamination techniques used in kiteboard manufacture.

So the plan would a be: build the main part of the board as a thinnish core of some kind of HD foam (12mm?) With top and bottom skins vac bagged onto it. Add hard rails into this as per what they do on kiteboards. So then I would have a hopefully stiff 7 ft vanguard style outline with no flotation, but also can't suck water into EPs core.

Then shape up flotation/deck part of board out of HD xps as per a softbard and glue onto the giant kiteboard section.
Route in plugs to finish.

Has anyone tried this kind of thing? I have plenty of epoxy, vac gear etc, but unsure of;

How thich do you reckon the core of the kiteboard section should be to give it enough stiffness?
What core material would be worth using?
Where do you get hold of foam like they use in softboards?

Happy for this to be a total experiment, I just keep imagining the thing snapping in half because the structural core would be so thin compared with traditional construction.

I have no probs with hard rails all the way round with this type of construction.

Any help would be much appreciated, think I'll start this instead of cutting the deck hump out of my ace.

Cheers chris

Get in contact with Dean Snow from Victoria, he is the guru on this technique.
Regards,
Quicky

Hold on Chris, " don't cut the deck hump out of your ace" ... seems to me as a strange expression

Had the same thought about this concept building mixing different type of foams doing this way a composites board.
As bodyboard using stringer as a spring and XPE foam as a shocker you can do the way you said:

"build the main part of the board as a thinnish core of some kind of HD foam (12mm?) With top and bottom skins vac bagged onto it. Add hard rails into this as per what they do on kiteboards. So then I would have a hopefully stiff 7 ft vanguard style outline with no flotation, but also can't suck water into EPs core."

You can find XPE foam in industry provider which been usedin packing tool boxes www.intercaoutchouc.com/division-transformation/usinage-mousse-sur-mesure.php , kind of cut out foam with water jet to fit and protect tools in boxes. This foam comes out in 200cm by 100cm in different thickness and density.

About " build the main part of the board as a thinnish core of some kind of HD foam (12mm?) With top and bottom skins vac bagged onto it. Add hard rails into this as per what they do on kiteboards. So then I would have a hopefully stiff 7 ft vanguard style outline with no flotation, but also can't suck water into EPs core. "
12 mm must be ok because the total thickness of HD foam once the XPE stick on the composite vac bag high density foamed sole of 12 mm thick will be around 10cm thick. So it won't snap .

As bodyboard you may adjust flexibility up different thickness and density of the different materials input.


When this sample will be assembled think you can shape tail block and design textured grip in the XPE foam deck. Also shape some channels in the bottom plan shape as you already did on one of your board , you will have the first channeled flexible Vangard board of the world

So go on your project, Chris, this board can be the future shape

Hi quicky and kami,

Thanks for your feedback, it is much appreciated.

Quicky does dean have a board company I can contact him through?

Kami, I thought I would shape a xpe deck and then cover with whatever the foam they use on soft board & body board decks. Do you know what this type of foam is called? I will have to work out the way to glue the foam deck to the board.

Cheers chris

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highvolume said..
Hi quicky and kami,

Thanks for your feedback, it is much appreciated.

Quicky does dean have a board company I can contact him through?

Kami, I thought I would shape a xpe deck and then cover with whatever the foam they use on soft board & body board decks. Do you know what this type of foam is called? I will have to work out the way to glue the foam deck to the board.

Cheers chris

Here is a picture of the material XPE in a 50mm thickness and 45kg/m3 . This density allows you to shape and doesn't need to be cover by a layer of foam because 45kg is already the density to finish top layer on bodyboard. Sanding surface of XPE is looking uggly and need to be gloss...that's the process i'm looking for : instead of sanding screen as to finish shaping blank , i did think about an hot wire slide on the rail as sanding screen does. Should leave a gloss surface that way...need to demo

Hi kami,

Thanks for the pic, I will go and have a talk with my local fiberglass shop this week. They have xps sheets for use in insulation. They are for use under concrete slabs so assume they are high density. The 50mm sheet I was checking out sure didn't want to bend easily.

Cheers chris

Hi Chris, XPS can be the solution to do a hard bending top layer because this foam is a sealed one then doesn't need to be laminate staying compressible as body board does . But sadly this foam is breakable, the board might snap.
From German board builder experienced people i did know that XPS can delaminate cause of its closed bubbles and molecular shape. German people call this foam "Styrofoam", it's a blue foam.
Need a demo , anyway.

I'm thinking I will build a mini Simmons style surfboard before scales ng up to sup size.

Yes, XPS would be the ideal foam material (imagine that: no water entries on dings !), except that when some air is generated by the foam (it happens during the life of the board) it has no way to go and get trapped between the foam and glass, and forces delaminations.

A shaper seems to have found a way to solve this problem by punching holes in the blank to anchor the glassing in the blank.
http://www.hydroflex-surfboards.com/hydroflex-technology/efc-surfboard-construction/index.php

I have seen garage builder using tools like this to prepare an XPS blank for glassing: (with thin spikes to reduce the amount of trapped resin)

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highvolume said..
I'm thinking I wilild a mini Simmons style surfboard before scales ng up to sup size.

Do it this way size up at SUP dim later on.

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colas said..
Yes, XPS would be the ideal foam material (imagine that: no water entries on dings !), except that when some air is generated by the foam (it happens during the life of the board) it has no way to go and get trapped between the foam and glass, and forces delaminations.

A shaper seems to have found a way to solve this problem by punching holes in the blank to anchor the glassing in the blank.
http://www.hydroflex-surfboards.com/hydroflex-technology/efc-surfboard-construction/index.php

I have seen garage builder using tools like this to prepare an XPS blank for glassing: (with thin spikes to reduce the amount of trapped resin)

As Chris prototype built XPS core has not been laminated. That's just stuck to a high density sole where fins plugs are fitted. So this is just the glue up side would be affected by air trapped between the foam and glass.
Colas, do you think it need to do holes spiked underneath

I dont think you need holes if the surface of XPS is limited, e.g. casings around fin boxes, handle.

If it is a large sole, I would try to do something to have a better anchor of the resin... holes? light sanding? raking grooves with a blade?