Build - Full wood UG Kipuna style board

[tungsten]

It's time for a new toy. This time round, I would like to present a full woody kite surf board. The built and shape is inspired by the Underground Kipuna (great fun board btw!). But I took it a step further

I wanted a playful board, sturdy, with LOTS of flex, and a deep single concave from bow to stern, for a comfy ride in choppy blown out shore break. Fast board. Snappy board, but not too loose. Sharp rails. Even less volume than UG kipuna. Carvy board. Kick-about-board.

I also started to play with a fin box concept allowing to adjust toe in, cant and fore'n aft fin postion: It's called 4wfs. As I was working on fins and fluid dynamics for the past year (that's why I was not posting much, been busy for the greater good of kite surf boards, sorry guys), I found better fins and adjustable toe in to be crucial for kite surf boards which usually should be faster than the odd surf board. But I digress; the one about fins is another thread (yes I started making my own fins), and I'll write it soon.

Back to the board. I took the Kipuna outline, made it slimmer, used a rocker curve a bit more pronounced in the tip, and a deep 8mm concave running through the entire board. This makes the board at the center line quite thin, in the tip 5mm, in the middle 11mm, increasing towards the tail to 13mm. I chose the Kipuna redecessed deck built to reduce weight and add flex while keeping a full-ish rail

[tungsten]

The Material I used is, as I mentioned, solid wood, and a ply stringer. I came across a cheap plank of Paulownia wood, 200cm x 60cm x 2cm. Paulownia is a bit like balsa, slightly heavier with 250kg / m3, but many times sturdier. It has great flex in it, and it is therefore being used as a core material by many TT manufacturers. Great stuff.

As I did not dare to bend it with steam (never done a piece that big), I decided I would glue pieces around a stringer and plane the resulting raw body. That's what I did:

A always I used Gorilla glue for the wood work (PU wood glue), a hand fad, a sander and a hand drill with a disc. No fancy tools here. This is still ghetto production style, and I want to keep it that way.

[tungsten]

The finished and sanded wooden core (80 + 180 grit) is ready to install the 4wfs adjustable fin plugs. Brilliant system.

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[tungsten]

After installing the plugs, the board is ready for laminating. (there's also 4wfs to be installed on top of the laminate, but I prefer the under-the-laminate plugs, which are tougher.

Isn't that a nice line?

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First I spread on a fine layer of thickened epoxy (thickened with colloidal silica, west system 406), and laminate 2 layers of 4OZ glass with epoxy on each side. The result is super sturdy, super flexy, and rather light for a full woody, with 2.900 grams ready to ride. Those white fins are crap, I'm just making the right ones for this board, have to adjust my molds because I was using FCS in the past.

[tungsten]

The artwork was done, as usual, by one of my kids. She's 8 years old now and skribbled a portrait of my wife and me. I added some wings in Photoshop, printed the whole thing on rice paper, laminated it between the glass, and that's that. Here's what we look like.

[tungsten]

And this is the finished board.

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Deck pad is as usual made of EVA gym floor mats, a cutter and a 80 grit grinder, they come in dead cheap at 10,00 EURO for the pack of 1,5m2. It's 12mm thick, just grind it down to the preferred strength. Came out a bit ugly, but it's super comfortable. Maybe I make another one. Some day. If there's no wind. At all.

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[tungsten]

Can you say "flex"?

[tungsten]

Well that is pretty much that! Now how does it ride? Well, this is the finest board I ever made. Great ease and comfort in bumpy waters, super fast, nice rail, and this deep single concave, together with lots of entrance flex, is like riding a flying carpet. A cushion. The words are failing me. You know Mako 150? Like that, but on a surf board. It goes upwind at crazy angles, which surprised me a bit. Those white crappy fins are too big, hence it's still a bit locked in (especially the rear fin sucks), but that's being taken care of.

Hey ho! The summer can come.

Measurements:
172cm (5'8") x 47cm (18,5")
weight: 2.9kg

Price tag:
Paulownia wood plank, 25,00 EURO
8m 4OZ glass, 40,00 EURO
0,8kg epoxy, 5,00 EURO
3 fin boxes 4wfs, 8,60 EURO
Deck pad 7,00 EURO
Total 85,60 EURO


Good winds,

Tungsten

P.S. as always, any old question, fire away.

[tungsten]

Update: how does it ride?

I had a couple high wind sessions on the board, around 30kn with gusts and wind chop. These are the circumstances where I usually had to break out a strapped board. With this new toy there's no need for straps anymore. Board tracks just fine, points high upwind which brings the boardspeed right down and makes for a controlled relaxed ride. Carving in the shore break, I put the back foot down and use the relatively small tail to brake effektively when needed. Very nice.

[feddomw]

Kick.

For the simple question: would you consider building one or more? Willing to pay of course. Cheap in materials, not so much in time and effort...

[tungsten]

Kick.

For the simple question: would you consider building one or more? Willing to pay of course. Cheap in materials, not so much in time and effort...

Actually I am thinking about it. The outcome is that good. I ordered 10 planks of wood the other day (which are not so easy to come by where I live). I am talking with a carpenter how we could make construction less time consuming using his machinery, and a board builder about doing the glass job. Shaping is always a hand job, but making the "blank" could be a lot faster, and a professional glasser is sure faster and better than me. Will let you know, wood should arrive by mid august.

[feddomw]

Depending on price, I could probably get more orders in. I know a few strapless riders....

[tungsten]

yeah target is a reasonable price. most production boards don't have a reasonable price IMHO.

[feddomw]

Yeah, production boards seem overpriced. FWIW, there are some costs that go into R&D and some boards are built quite well, but almost ALL are built at the Cobra factory in Thailand, so we should be seeing more economy of scale than we are....

[tungsten]

I see many production boards 50 to 100 per cent more expensive than a hand shaped epoxy board from the local shaper guy. Cmon. Should be the other way round.

Bring your biz to the local shaper, you won't regret it.