Thought I should build a board. Problem is I only have oldskool board building skills . I wanted to make it without vacuuming , that scares me and I don't have those tools.
So I decided to use new materials and old fart skills.

Styrene slab with 3mm ply stringer.






Roughed out shape.
145 liter ish , 78 wide , double concave to spiral V at back.




4 oz carbon ,inegra cloth laid at 45 degrees.




Sandwich material , 3mm cork top and bottom , 3mm HD EVA foam around rails.
I recklessly gouged out the styrene foam around box , track and plugs and filled with a hard two part expanding foam and re routed the holes.
7.2 kg at this stage with fittings , estimating around 10.5 kg when finished ( the same as a 145 Xcite ride epoxy )
Next will be to cover in glass and use a clear UV stabilised epoxy. Surfset Flex resin from Sanded Australia.

Nice job ,certainly looks strong enough .

what logo you gonna put on it ....IMAX,mad max ,to the max .,?

interesting how it runs .

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Tardy said..
Nice job ,certainly looks strong enough .

what logo you gonna put on it ....IMAX,mad max ,to the max .,?

interesting how it runs .

In the old days it was SeaThru sailboards , but Mad Max boards has a good ring to it . Let's just see it it floats first
My theory on design is ... I have two Xcite rides 160 an old one and a new one. I prefer the older one , it planes earlier and is faster , but not that fast. The newer one turns better and is narrower. So I used the rocker of the older one , the outline of the newer one and the concave shape of an old Starboard Go that is really fast.
Thats my theory .
I must also thank the people who's brains I recklessly picked ( u know who u are ) to make this happen , gee hope it works

Nice. How did you get the cork and 3mm foam to behave without bagging it?

^^^
the top cork I epoxied and taped it down , totally covered it with fat tape.
The bottom and rails I used contact adhesive , it sticks like Sh.t to a blanket and the resin over the top does not effect the glue . ( I did tests ) . I hope the constant flexing of the board doesn't effect the glue.

Your shaping is magic :)
Its not easy...


Now to clarify - EVA foam on rails ?
And contact adhesive from styro to EVA?

Nice result Imax, looking good. I will be very interesting to see how your materials work out, if they're good you could start a whole new DIY technique.

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Mark _australia said..
Your shaping is magic :)
Its not easy...


Now to clarify - EVA foam on rails ?
And contact adhesive from styro to EVA?

From memory, there's a layer of well sealed fiberglass between styro and contact cement

Imax1, looks great mate. Cant wait to see the finished product n on water test. Contact cement should withstand flexing. Its quite a flexible glue when cured.
Call it "Maxi Ride" for dudes in the 'Tonner'club. (over 100kg).
Bring it to Qld if you come for a reccy n beers. Hats off to you!!

It all looks very nice!
But now you have me wondering what kind of a blank you used. You say styrene, but contact adhesive as I know it (Pattex and its colleagues) would eat it. Where did you get it? It seems to be getting ever more difficult to find blanks, at least her in Europe.
Keep it up, looking forward to seeing the final result.

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Imax1 said..
The bottom and rails I used contact adhesive...

Thanks, such a simple solution but one that never crossed my mind. I'd be interested to hear an update down the track sometime how that holds up over time.

I'll throw my wager in for it being totally up to the task.
Anyone with more technical experience able to confirm for me that the bulk of force between skin and the sandwich foam is in sheer?

It was only at second glance I noticed your superb compressor-pram-combo. Why on earth did I give our pram away when our children had grown?

To make the blank i bought a super square block of polystyrene.
Then cut a template to perfectly match the rocker of another board. I used this template and transferred the curve to the 3mm ply . So now i have the bottom rocker curve in the stringer. Then made big calipers to measure the thickness of the board at intervals , cleaned it up and now have a perfect sized stringer.
With a hand saw i cut the blank down the middle. I flipped the cut sides to the outside and using the clean edges glued the stringer inside keeping everything flat and square.
Then shaped the foam down to the stringer , easy . Started with the bottom and could keep checking the square sides so i wouldn't go wonky.
The top was done by eye and used some cardboard templates for the rails.

The foam was coated with resin with a roller before putting the cloth on then squeegeed . Super light sand then another light resin coat with roller to make sure the foam was sealed so the glue wouldn't attack the foam inside.

Dude.... do yourself a massive favour and buy a vacuum pump. You'll never look back. Great work!

^^^
If I make more boards I probably will.
It would be nice to use half the resin and bog it up all over. I wanted to see the cork finish at the cost of some weight. The cork did soak up a lot of resin because I didn't want to see any air bubbles. I'm still hoping for under 11 kg.

Its finished



























Hope it floats !

Nice work Imax !! It looks great. Good finishing details.
What is the finished weight?

Cheers, Hoops

^^^^
11.5 kg with straps.

Looks fantastic mate, but with a board that wide and fin that deep, I'm surprised how inboard you have the straps?

^^^
With my weight it's like a wave board .
I have those positions on all my boards.
It gets real rough where I ride and feels the best there.

Sweet Action Imax , Corker !!!

Nice,

Imax1, youve done it again. Another impressive project. They just keep coming. When do you get time for work or beers?

^^^
I had to stop at beer 4 when shaping or it could have turned ugly !

Looking good, I think the cork would have added most of the weight, looked on the internet and its like 400kg per m3 whereas corecell or divinicell is about 80kg. Im really curious as to how the cork holds up and keeps the inner and outer layers an equal distance apart especially under the heels. The pvc's seem to eventually fail in this area, high density cork might not. Can you go out and absolutely hammer this board, as in lots of jumps, lots of use, for scientific purposes.

I'll give it a dam good thrashing.
Actually the cork sheet wasn't that heavy at all . The problem was that it is so porus . It sucked up a huge amount of resin when laying it up. If it was bagged it would have been lighter but I wanted to see the cork without any air bubbles. About 1.5 kg resin including the glassing per side. Ouch !
However it is solid , I think I could have got away with less glass.

very impressive :D

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Imax1 said..
I'll give it a dam good thrashing.
Actually the cork sheet wasn't that heavy at all . The problem was that it is so porus . It sucked up a huge amount of resin when laying it up. If it was bagged it would have been lighter but I wanted to see the cork without any air bubbles. About 1.5 kg resin including the glassing per side. Ouch !
However it is solid , I think I could have got away with less glass.

Good, tnrash away. I wonder if you could pre treat the cork and lightly roll on say 80ml resin with a 100 mm paint roller. Then let it dry before laminating. Ideally lightly spray with resin.

^^^
I actually did that after gluing it down , two minds alike !
When squeegeeing the glass over the top the cork was sucking the resin up like a sponge . It is amazing how porous cork is even though it looks relatively solid . I think the cork itself sucks up resin .
When i did tests before diving in i was amazed how tough resin soaked cork is . ( impact tough not tensile strong ) .
Bagging wetted glass over the cork would be soo much lighter , but i suppose you would loose the solid ( and heavy ) as a rock sandwich material .
I still think bagging cork would be perfect . Mabee next time ?

That is epic!

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Imax1 said..
^^^
I actually did that after gluing it down , two minds alike !
When squeegeeing the glass over the top the cork was sucking the resin up like a sponge . It is amazing how porous cork is even though it looks relatively solid . I think the cork itself sucks up resin .
When i did tests before diving in i was amazed how tough resin soaked cork is . ( impact tough not tensile strong ) .
Bagging wetted glass over the cork would be soo much lighter , but i suppose you would loose the solid ( and heavy ) as a rock sandwich material .
I still think bagging cork would be perfect . Mabee next time ?

If the cork sucks resin then if you had bagged glass on it may act as a bleeder type material and suck to much resin out of the glass, justca thought.
So you sealed your cork with epoxy let it dry and it still sucked resin?

I think you should have a look on swaylocks forum guys were doing lots with balsa as a sandwich maybe they might have cork sealing ideas. I know they seal their EPS foam before glassing.