Advice on building a chambered (or hollow) surfboard

General Discussion
1

Hello and Merry Christmas.  I’ve been doing a lot of research on wooden surfboards and plan to take on this project when I get home to San Diego in Feb (I’ve been working in a land-locked country for the past 10 months).

There isn’t a whole lot of information on Chambered Surfboards on-line, and it probably took me less than a day to read anything I could Google on the subject.  That being said, I’m hoping you guys can give me some advice.  As a staring point, I"m using the template and book written by Chad Stone.  My goal is to build an 8’ longboard.

So, here are the questions:

What is the most practical wood to use?  I understand that a chambered surfboard has the potential to be heavy.  Chad Stone recommends using 2x4x8 luimbar.  I don’t know yet how readily available cedar is in that length. 

Does anyone see any issue with taking red cedar planks (fencing material) and planing/joining them to make 2x4x8 lengths?

What are the pros and cons of glassing the board?  On one hand, I think glassing adds durability, but if the bottom and deck aren’t too thin, will marine varnish be adequate?  Or should I use epoxy resin/varnish without the fiberglass cloth?  If I glass the board, I’ll probably send it out to get professionally done.

What is a realistic weight goal for an 8’ longboard? 

Lastly, what is everyone’s opinion on a chambered versus hollow board?  Hollow board kits are readily available, but to me, there is something appealing about taking a solid slab of wood and forming it into a board.  Am I missing the boat on this one?  Is there any evidence tha suggests that hollow boards are better with respect to performance, construction, aesthetics, etc?

Thanks in advance for the help.  Any advice you can give me would be greatly appreciated.

Ray

 

 

 

 

 

 

 

 

2

 

If you mean 8 ft long 2x4s, yes. You can easily get western red cedar in 8’ lengths.

But…

1 You won’t get an 8’ board out of them. A 7’10, maybe.

2 2x4 isn’t nearly wide enough to get any rocker. While you may be thinking that 4 inches is enough for the thickness of a board, once you factor in the rocker you are looking at more like 8 inches. 6 at the very least. Also, a 2x4 is actually 1-1/2 x 3-1/2. So, keep that in mind when choosing material. A 2x8 would be 1-1/2 by 7-1/2.

3  Western red cedar is very expensive. A chambered board built from it will waste about half the material. Do you want to throw away half of the wood you paid for?

 

Red cedar also has a pretty high oil content. Not the best choice if you want to glass it or even use an alternate finish. Tough to get a good bond without some surface prep using a binder or conditioning agent.   It is also relatively soft and I would not forego fiberglass. The most beneficial properties of red cedar are its water resistance, uniform grain, and relatively light weight.

 

Two friends of mine who are experienced surfers and woodworkers have built chambered red cedar boards. Both came out a lot heavier than a regular board of the same size.

3

Hollow boards (planks over a fish bone framework) are built up, from the inside out.  Chambered boards, like foam boards, are shaped (sculpted), basically coming at it from the opposite direction, working inward from a larger shape.  With a chambered board, sections have to be cut and glued together, and each section hollowed out. 

I like building hollow boards over a framework, never used a kit, always designed and built my own from scratch.

I have never tried building a chambered board, so I can’t help you there.  But I have seen some beautiful chambered boards, and I think if you are skilled at shaping surfboards, and skilled at shaping wood, you could make a nice one.  I have also seen guys glue up the blank, have it cnc machined, then take it apart, chamber the sections, and re-glue.

I think balsa and paulownia are the popular woods for chambered boards.

For cost reasons, I use redwood and cedar (mostly redwood) from the big-box stores to build my hollow wood boards.  My first board was a 6-8, and it weighed 17 lbs. finished.  I’ve learned a few tricks since then for keeping the weight down.  I am finishing my 12th board (8th hws), a 7 foot egg, and it is probably gonna finish up around 11 lbs.  I built a 9-6, and it weighed 18 lbs.

Glassing adds a strong shell to the board.  With wood boards, it is not always necessary, some wood boards are finished with epoxy resin no glass.  And there are some other variations out there.  I pretty much always glass, although one board I didn’t glass the whole thing, just the rails.

If you’ve never glassed before, you will find that, while glassing isn’t hard to do, it is hard to learn, and it is hard to do well.  But like anything, that makes it that much more satisfying when you succeed at it, if you that’s your desire.  Probably cost you about $100 materials to glass it yourself, or pay about $300 to have it done.  If you figure your time as worth anything at all, paying to have it done is probably the cheaper route.  If you have the time and the motivation, and love a challenge, then glass it yourself.  I have always glassed my own boards, but I have struggled to learn the finicky art of glassing, still trying to learn it, after 11 boards completed.

I would love to someday build a chambered board.  But cost-wise, I think fish-bone boards are cheaper.

Did you see this thread? http://www2.swaylocks.com/node/1029108

You may enjoy visiting the wood-board forum as well, http://www.grainsurf.com/forum/search.php?search_id=active_topics

4

Elsewhere the western red might be expensive, but here on the west coast it is cheaper than balsa. I just picked up 4 - 13 foot full 2" x 6"-s  rought sawn for 231 bucks, the sawing is clean enough that barely an 1/8" is lost in planing.

I have a source for good balsa also, recently bought over 400 BF of 14 foot wood.

If your a going to be in Socal I can arrange wood for you

5

**raymond take up jims offer **

 

   cheers huie

6

If wood waste is not an issue, go with your gut. If it is do the hollow. Cedar and pawlonia here are both excellent woods to work with. Would really love to do a chambered WRC as I really love that wood’s scent. It’s almost $50 us here for a 6’ 2x4", pisses me off and fills me with aggravated frustration actually. Where is my hammer? Nah, I’ll go trim the rail pieces instead.

7

Bob Mitzven and Rick Klow got 2nd place in the 2009 Billabong art of Shaping with their pair of chambered WRC fishes, they were purchased by a Japanese client, he left them in his locked car in Tokyo, they exploded.

Rick brought them to me to do an autopsy, I hand split them lengthwise on the center glue line and then with a fence split them 5 inches out.

They were chambered flawlessly, down to a 3/16" skin, but the chamber walls were also only 3/16", not nearly enough grain to hold the top and bottom together, they split in the center of each rib, with one spliting right out the end of the rail.

One of my old pals that moved to Costa Rica had been making balsa boards there, when he finished the chambering, he would cut strands of carbon fiber long enough to touch the deck and bottom of each chamber. He’d mix a batch of expoy, wet out a single strand, go up the side of the chamber wall and flair out to the deck and bottom about a half inch. It was enough to keep the top and bottom connected in the tropical heat.

The 17 balsa boards I built for the movie “Surfing Through Time” were air freighted to O’ahu, I drilled a 1/32nd hole in the bottoms of them so they could breath at 37,000 feet, nothing that couldn’t be fixed with a drop of solar resin

8

…so Jim, that s the definitely answer that a chambered board should have venting…more a longboard, I guess, due to those noses exposed directly to the Sun for hours.

 

-Also, the other day a customer stopped by my wshop with a hollow Balsa, cedar and kiri (pawlonia) board in which he cut a small part in the tail to let the board breath and let the humidity air and some water to let it go.

The board has a bronze vent may be home made (I did not checked it) but the screw unscrewed and water entered finally…the Balsa unglued from the ribs in 1/4 of the board (deck and bottom)

In my opinion, chambered Balsa are far better for a functional board, also look better than most hollow boards that I have seen.

9

With a hws, venting is a must.  With a chambered, I think it may depend on how thick the outer shell is left when cutting chambers.  Someone here, Kayu I think it was, said they have seen chambered boards with no vents that have seen years of service.

As far as a functional board, there is no reason that a hws wouldn’t function just as well as a chambered board, but as a daily driver, its hard to beat a foam board.  Wood boards tend to be pretty strong, but the problem with a hws is that the air inside usually contracts and creates a negative pressure (suction) when the temp drops, as when taking it from the car to the cold ocean water. 

So any ding, or any pinhole, or any untightened vent plug, will allow water to be sucked in.  Then you have the problem of removing the water, drying the inside out, finding the problem and fixing it, repairing any warped wood - much more hassle than a simple ding repair on a foam board.

And yes, if you forget to open the vent when the board is in a car or in direct sunlight, the air inside can expand to the point that they blow apart.

With a foam board, the air is divided into all those little cells, so there is no one big chamber of air expanding and contracting.  And if a foam board dinged, it could still be ridden.  Water intrusion would be minimal, in comparison to a hollow board.  If a foam board broke in half, you could still hang onto the half with a leash, and stay afloat.  Not so much with a hws, although I will say they rarely break in two like a foam board.

As far as looks, I think guys like Paul Jensen build awesome looking hollow wood surfboards, and a lot of guys who post here too, boards second to none in appearance.  However, due to the difficult nature of the building technique, and maybe due to many hws home builders being a bit naive regarding the finer points of surfboard design, I sometimes see aberrations of outline or foil or rail shape that make me cringe.

Nevertheless, wood boards are really fun and challenging and hugely rewarding to make - as a home builder, that is.  Even Paul Jensen has said he wouldn’t make enough money selling them professionally to make a living.  They can be fun to ride even 'tho not generally viewed as “high performance” in the widely accepted form of the term.

I can usually go to the big box store and buy enough redwood to build a hws for about 30 to 40 dollars.  Because of the slow process of building a hws (typically measured in months, among the homebuilding crowd over at the tree-to-sea forum), their need for venting, and the difficulty of matching the light weight of a foam board preferred by most mainstream surfers, they will never be popular with professional shapers, or most guys in the water.

I think they are made and ridden and appreciated by a small fringe group of people who just enjoy the process, and the somewhat unique product that results.

10

Terry Martin felt that the hassle of chambering and the resulting risks were far greater than the weight savings in a balsa.  Balsa shapes are designed with their weight in mind, and if you want light, then a skinned eps would be more appropriate and you’ll get the same look.  Lot more durable than a chambered.   All hollow boards need some sort of vent and interconnection of the chambers, the expansion rate for hollow is 2x as fast as eps when heated.

11

This is the same concern for EPS boards, I hear on a daily basis on how “they” use “fused” foam and it doesn’t assorb water. bullshit. 

When you have an enclose atmosphere that was built at i:e 30 MB, any atmopspheric change is like the enemy at the gate, it either wants to get in, or get out, put that board that was built at 72 degrees and immerse in 58 degree water, it sucks, air, water, it’s all the same, leave it in a car that is 140 inside, it blows.  I shaped a few Channin’s recently, glassed with carbon rails, one of the customers came by to give me a ride report, while we stood there, I looked at the board and water was squirting out of a pin hole in the carbon lap. With this kind of equipment you have to treat it right, we glassed some Harbor’s with early Austin Foam, Rich brought them back very unhappy, the customer said he did NOT leave it in the sun, the foam was melted under the logos, melts at 185 - 190, not what is concidered “normal” surfing conditions fro anything but polyester or solid wood.

 

 

Balsa’s are NOT made with the weight factor as a ride benchmark, it is simply a heavier medium, you either learn to like the way a 35 pound board rides or you build one that is much lighter, chamber it. Balsa was the lightest material they had in that era and the search was on to build them lighter

12

Thanks for the great feedback.  You’ve given me a lot to think about, and I’m gonig to take a step back and rethink if chambered is the way to go.

Huck - Thanks for the feedback.  I’m going to do a bit more research on hollow building techniques.  From what I’ve read yesterday and today, it doesn’t seem at overwhelming as I had first thought.  I also agree with you that there is a small fringe group that appreciates wood boards. 

Jim - Thanks for the offer.  I may take you up on it when I get back to the US in Feb.

Ray

 

13

Words of the wise jimthegeius ! Hallow boards blow or suck! people who build or own hallow or chambered have to know their care and feeding! If you don’t you will screw them up real fast !! Every time I see one of those rotory molded kayaks being drug across the parking lot by some tourist it makes me think  that there are a lot of idiots out there that would do the same with a wood surfboard !! .  for raymond , chambered boards are good for the expert shaper ( lot of wood wasted in chambering) so they are expensive. Hallow built boards cost less for materials but take a lot of time !!and different type of skills. Chambered board are shaped so you can refine as you shape. Hallow boards are engineered,  built in the mined before you even cut one stick of wood !! Two different animals, the only thing in common is they are wood !!

14

I fill the chambers with fitted blocks of EPS , and epoxy it into the chamber…had no explosions or delams for years…it does reduce the pressure compared to an air cavity… the boards have a bit more drive also , being closer to a solid mass.

15

Honestly brother, if you enjoy surfing and woodworking, build, or buy a foam core surfboard....., and build furniture.

sickdog

16

From what I’ve seen, and I’ve seen quite a few, these are about the best hollow wooden boards being made right now. The shapes are not compromised in any way, shape, or form. Lots of thumbnail pics of the process that can be clicked and enlarged.

http://www.haleiwasurfboards.com/theprocess.html

17

beautiful boards!  They claim over 150 man/hrs. per board, and a year to fabricate the press, jigs, etc. they use to make 'em.  Its a different system than most garage builders, for sure.  I bet I’ve done a couple that could rival them on hours 'tho, LOL - those boards must cost in the ballpark of $6K or up.

18

Along these lines of thought and effort not withstanding; anyone ever tried (or considered) breaking the sticks apart after shaping and instead of making multiple chambers for each stick, make one chamber per stick from stem to stern and then add multiple “columns” of wood or EPS or ?? as support to each stick before the final re-glue? I’ve only done one chambered board and found the chambering process to be very time consuming (not that I don’t enjoy my time in the man cave).

Happy New Year Ya’ll !!!

CMB

19

If you were adding foam as in Kayu’s quote that you posted, would you even need the intermediate wood supports?  Wouldn’t the foam serve the same purpose?  Just asking.

20

Actually , the guys that do Dick Brewer’s balsa blanks in Hawaii use struts inside the chambers, made of spruce , ( vertical grain), which is a very sound idea to halve the internal span of the chambers…some surfers just have a specific preference for hollow chambered boards , but my best results have been with fitting the chambers with foam…a bit of extra fiddly work , but   worth it to eliminate (or greatly reduce) internal pressure and better foot support…Ideally , chambers should be oval in shape , which adds substantially to deck impact strength and overall structural integrity of the board…a box of different size forstner bits is a good investment !