First Hollow Wooden board pix.

General Discussion
1

So, I spent some time putting together a rudimentary website dedicated to our first hollow wooden boards, etc. It’s at http://www.gallardosurf.com

We’re pretty excited to glass them up next week and take them for a spin.

Dave

2

Board Building Process. Click any of the images for a larger sized detail view.

[=1]We start by building a frame: [center]
[ 5]Then, we carbon fiber the top and bottom decks and attach: [center]
[ 5]Next, we start building balsa rails: [center] [url “http://www.pbase.com/bootslondon/image/48265495/original.jpg”]
[ 5]Then put fin boxes on them: [center]
[ 5]Shape the rails, and the board is ready to glass and surf: [center] [url “http://www.pbase.com/bootslondon/image/48265490/original.jpg”]
[ 4]The process is not fast. Every step requires curing times and gluing times. This process can take months to get here. The end results are way worth the effort[/]
thanks Dave !!
having watched my mate “Hicksy” make a couple, I totally agree with your statement " the process is not fast " [an UNDERstatement , actually , I would say !!]
What sort of weight did it end up being ?
cheers !
ben

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http://images.google.com.au/images?q=chipfish&hl=en[/center]

3

We have still to glass, so I’m not sure yet…

Dave

4

Also, I failed to state the obvious in my first rendition (sometimes excitement makes me post too quickly): Without Paul Jensen and the help from everybody here in Swaylock’s we’d NEVER be where we are at now, and we offer our sincerest appreciation for the help in getting to where we are at now, and hope to contribute what we’ve learned to others that choose to make HWS in the future.

Dave

5

looks really good, but are the side fin boxes just floating in the body? or has the frame been made to support them?

6

Hey Dave,

that’ll look so sweet when it’s glassed. Nice woods. That’s a nice shop you’ve got there aswell, fancy a swap for my crappy garage?

Jase (MMM)

7

Have several question/comments. Part of this comes from being an engineer, where nothing is ever good enough, so please understand that I’m more curious than critical. I am getting to think about making a hollow myself, based on a friends Dick Brewer hollow balsa Pipeliner-styled pintails (I think he has six of them now and gets several new each year).

a. Do you space your ribs on an inches-apart basis, or as some fraction of the board length? Are then (as they appear to be) evenly spaced, and why?

b. looks like no special support under a rider’s back foot, where most of the stress is… comment?

c. the long rectangular cutout in the ribs offers little support to a rider’s weight. It means that the remaining rib, midway between the center stringer and rail, has to support quite a bit of bending stress. I’d have thought that one would leave some vertical “posts” in the web of the rib, or that ribs cut with circular holes would better support the vertical loads on the rib.

d. Please describe the material and thickness of your skins.

e. I note you use carbon fiber cloth inside the (deck and?) bottom skins. I assume this is to provide adequate bending strength. My understanding of carbon fiber is that it’s very expensive but very strong in tension. It would seem you really only need unidirectional cloth on the skins, comment? Also, how are the ribs and stringer joined to the top and bottom skins? Apparently you have found no need for glass or carbon fiber to join the skins to the ribs?

f. In the end, this is a lot of work to produce something that (aesthetics aside) is only a core to be glassed over. I guess I have to take it on faith that the aesthetic end justifies the means.

Charlie

8

No, the fin boxes are supported by balsa blocks done on the inside of the board specifically to support them.

Dave

9

[=1][ 2]in response to your questions:

a. Do you space your ribs on an inches-apart basis, or as some fraction of the board length? Are then (as they appear to be) evenly spaced, and why?

We space the ribs roughly 12 inches apart. We follow Paul Jensen’s (www.hollowsurfboards.com) guidelines.

b. looks like no special support under a rider’s back foot, where most of the stress is… comment?

So, the stringer is reinforced with carbon fiber, the deck is reinforced with carbon fiber (underneath), we DID put some balsa in the back area for the fin boxes and the leash plug, but I believe there is a great amount of strength from the wood and carbon fiber. I snowboard (and have made many snowboards), and I am in NO WAY an expert, but carbon fiber and wooden snowboards handle my large body landing on them from big jumps, I would guess the decking would at least hold up the same way. The rails should also provide more strength to the surfboard.

c. the long rectangular cutout in the ribs offers little support to a rider’s weight. It means that the remaining rib, midway between the center stringer and rail, has to support quite a bit of bending stress. I’d have thought that one would leave some vertical “posts” in the web of the rib, or that ribs cut with circular holes would better support the vertical loads on the rib.

Again, while I’m no expert, I don’t believe a lot of the strength is coming from the ribs. We’re definitely going to find out. The Strength is coming from the inner stringer, inner rails (attached to the ribs), and reinforced deck.

d. Please describe the material and thickness of your skins.

The material we used for this set (our first) of boards was Fir with purpleheart for the stringer. The rails are balsa. The thickness is roughly 1/8"thick with 6oz Carbon Fiber underneath. We milled the fir down from an old tree. Bandsaw, thickness planer and thickness sander is your friend (and an enemy of your free time).

e. I note you use carbon fiber cloth inside the (deck and?) bottom skins. I assume this is to provide adequate bending strength. My understanding of carbon fiber is that it’s very expensive but very strong in tension. It would seem you really only need unidirectional cloth on the skins, comment? Also, how are the ribs and stringer joined to the top and bottom skins? Apparently you have found no need for glass or carbon fiber to join the skins to the ribs?

We only use one layer or CF. It’s a strength -vs- weight thing, but we’re still learning and experimenting. The glass on top is going to help with strength as well (and sealing). We joined the skins to the board with Liquid Nails per Paul Jensen’s instructions.

f. In the end, this is a lot of work to produce something that (aesthetics aside) is only a core to be glassed over. I guess I have to take it on faith that the aesthetic end justifies the means.

It’s a bit of everything. We do it for the craftsmanship involved. We do it because they’re beautiful. We do it because we love surfing. We’ll learn a lot from surfing on our first ones. We’ll continue making them. I’ve always wanted to do wooden surfboards, and when I got my butt kicked over and over and over by Paul Jensen on his hollow wooden boards, my buddy and I decided that we’d like to take a stab at building them so that we can compete in the break with him. :slight_smile:

Dave

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