Balsa board project

[Bryan Jackson]

A look at my balsa board project (you can view the pics in the photo gallery under "boards").

I am still putting some finishing touches on this board. Refining the rail outline. Thinning the tail a bit. Balsa takes a lot more work than does foam but is also more forgiving and so much more pleasurable to work with.

Shapewise this board is modeled after my favorite board, my 5’10” Blast rounded pintail (thanks Bud) with some minor modifications.

It is 5’9” with a bit less rocker, a different rail profile (softer in the nose and only one stinger in the tail) and will be a 2+1 fin set-up (single center fin with smaller side stabilizers). I envision this board as being a trim and glide type ride still able to pull some hard bottom turns and hang in the tube.

But clearly the most significant aspect of this board are the materials used in its construction. Primarily balsa wood with redwood stringers, mahogany tail and nose blocks (not shown in pictures as they have not been added yet) and a main single fin with two smaller side stabilizer fins (not yet attached to board but shown in picture below board).

Why wood? Partly the beauty and challenge, but also a desire on my part to get away from what is arguably some of the most toxic materials on the planet: the resin used to blow surfboard blanks !

I had long wanted to build a board almost entirely from scratch, would perform reasonably well and would be, at least to some extent, somewhat more environmentally friendly than foam .

I used marine epoxy to glue up the blank and will be glassing it using fiberglass cloth and UV inhibited epoxy, which is easier on the environment (less VOCs than polyester resin) and also has the added advantage of a greatly increased strength to weight ration and tends to last longer.

Even though balsa makes for a heavier board it has certain advantages . (Actually it is possible to bring the weight of a balsa board down to nearly that of a foam board by chambering, that is hollowing it out, but this requires a lot more work ). It requires less glass and resin as it is inherently stronger than foam blanks. It is much longer lasting as wood retains its memory much, much better than a foam core and fiberglass resin board, whose memory is almost entirely retained in the fiberglass skin and which gradually breaks down over time (which is why foam boards eventually wear out and go dead). And, of course, a wooden board has its own natural beauty .

To make my own balsa blank I hand selected several balsa planks at Frost Hardwood here in San Diego, each about 10-12’ in length and approximately 3”x3.25”, two 12’ redwood planks approximately 1" thick and 3 3/8” wide (at Home Depot), and a piece of Philippine mahogany (about 1’x2’) for the nose and tail blocks. (The fins are 1/8” 4-ply birch plywood glued with epoxy to a 1/8” polycarbonate core for flex.)

Before gluing the planks together into one large blank, I first cut them to length and pieced them together, drew the outline of the board on top, separated them and then used a rocker template to rough shape each plank, much like a boat spar is shaped during boatbuilding! Of course, I didn’t try to shape each plank down to its final curve, but left a semi-rough outline, being sure to leave plenty of material for final shaping! Then I glued them all together, two at a time. (The gluing up of the blank was a bit tedious and required a lot of work and patience. Once done, however, the real fun of shaping started!)

When finished it will have a Parkes pad as Balsa is a rather unforgiving surface, especially with epoxy glassing!

I estimate I have already put in well over 100 hours on this project, but it will be time well spent !

I already have my next balsa board project in mind: a Lis style Fish .

[Jon Manss]

Hi Bryan, Having worked on several wood projects that required creative thinking on just how to get it done. I congratulate you on blank your lay up scheme. You put a lot of thought an care from glue up to glassing. If for nothing else you have a great display of craftsmanship. I find the road or adventure of the project to be just as rewarding as the final piece. I've been asked many times if it was hard to give up the work once done for a custumer. I tell them that with every project I get to keep the knowledge and hands on experience and that is priceless in my book. Nice job keep it up. I would love to see your board in jalama. Jon

[Bryan Jackson]

Hey Jon,

Thanks for the compliments. Unfortunately I won't be able to make the Jalama gathering although it looks like it will be a great time (I read posts). But if you or any other KBer down San Diego way wants to get together just let me know.

No telling how this balsa experiment will ride but it should be interesting . I've only ridden one balsa board in my KB career and that was a Fish with almost no rocker . It went OK (actually it was quite fast) as long as you didn't try to turn or take any steep drops !

Hopefully my board will perform a bit better. It should be ready to hit the waves in a couple of weeks, another month at most (As Orson Welles used to say, "no wine before its time" ) . I'll post a full report as well as pics.

[Bryan Jackson]

Reply to comments posted by Dunc and Jon on photo gallery:

Jon, you’re right, I was just lucky in choosing redwood stringers . I did it for looks more than anything else. My first plan was to build the board entirely out of balsa in order to avoid problems. I was worried that redwood stringers might unnecessarily complicate things. The balsa does cut or sand faster than most other hardwoods (both an advantage and a problem), redwood included. I can indeed feel the difference between the two woods. In fact, even one piece of balsa will sand noticeably differently than the next.

However, it actually worked out rather well. The redwood stringers served as guides in shaping the board. In addition, I had originally planned on a more or less flat bottom with a slight roll towards the rails. What actually happened is that channels formed between the redwood stringers. To put such channels into a foam blank would have required a great deal of skill and care, but these formed naturally !

Yes, Dunc, getting away from “toxic foam” was a large motivation in building this board. (Isn’t it rather ironic that surfers claim to be so in tune with the environment yet freely use, abuse, and misuse the Earth’s resources in building their boards ).

“Is your board solid balsa?” - Yes.

Although it is possible to hollow out a balsa board (called chambering) to save weight, that involves a bit more work. You must first rough shape the blank almost to the point of completion, then carefully cut it apart, hollow it out taking great care not to make the walls too thin, glue it back together and do the final shaping (did I say a bit more work!) .

All of the work on this board was done entirely with hand tools. If I was going to hollow out a board I would definitely want some type of table saw to get as accurate a cut as possible when I cut the blank apart.

Chambering a balsa board will bring the weight down to that of a foam board but, in addition to the added work it is fraught with danger. If you make a chamber wall too thin you could easily break through either during final shaping or the wall could be weak enough that it might actually buckle during use.

This being the first balsa board I have built I chose to keep it relatively simple. I did consider honeycombing the planks and actually did do a test drilling to see how that might work, but in the end decided not to fool with it. Perhaps now that I have gained a little more experience I will on my next board. In any event it will be interesting to see how this board, which is solid all the way through, rides in comparison to a board which has most of its weight concentrated in the outer skin .

“How much does it weigh compared to a standard board?”- I haven’t taken an accurate measurement yet, but right now (unglassed) it weighs about as much as my 5’8” Pavel Fish which has a triple stringer and a very heavy duty Volan glass job.

Since I will be glassing this board with lightweight cloth and epoxy resin (possible since the board’s strength is not at all dependent upon the glass job), I anticipate that it’s finished weight should not be too much more than it is now. I also have some more sanding to do on the rails and tail which will bring the weight down a wee bit more.

Obviously this board will not be for boosting airs (which I am not into anyway) or snappy turns, but I have found that in some conditions a heavier board has certain advantages. For example, in juicy waves I much prefer a rock solid board underneath as it just feels more secure. Bigger waves call for bigger moves and have more power to propel the board so weight is less of a concern.

Anyway glad to hear that seeing my board made you happy, Dunc. If you have any other questions feel free to ask. Perhaps there will be a balsa board Renaissance (“Back to the Future”) !

[Steeno]

keep it up bryan, it looks awesome.......i want one

[surfhorn]

FYI- John Mel at Freeline has shaped several balsa KBs over the years.

[fooj]

Bryan,
Nice. You got my wheels turning. How did you get your info, did you use a set of plans as a guideline or gather it from here and there? I think I would like to try this. Jeff.

[Bryan Jackson]

Hey Jeff,

I did some extensive web research to get basic info both on balsa wood in general (its characteristics, natural history, etc.) and also on shaping a balsa board. One really good site I found is www.solidbalsa.com. The Swaylocks site also has few threads about balsa boards. There are others as well (just type in "balsa surfboards").

I used my Blast 5’10” rounded pintail to make a template. I kept the Blast close at hand during shaping but more for a general reference in order to avoid making any major mistakes. I wasn’t really trying to make an exact copy of that board and I had some ideas of my own I wanted to incorporate (e.g., rails and tail) plus balsa, like any wood, has its own idiosyncrasies and pecularities one has to learn to work with (like originally it was going to have a full tail but when I cut the outline in the blank there was a funky soft spot in the tail but that worked out OK as it was in the perfect spot for a single stinger !).

My main fin was inspired by www.hollowsurfboards.com which has a really good discussion on fin design. That is also where I got the idea for sandwiching a polycarbonate core between plywood. My stabilizer fins are my own design.

I have done a few woodworking/carpentry type projects here and there so I have a few rudimentary skills working with wood. It is not too difficult if you know your basics. I have done extensive repair jobs on foam boards and even shaped a couple in the distant past so I had that area basically covered as well.

You can buy a balsa blank already glued up and ready to go. They are usually built with long boards in mind so it will be ten to twelve feet in length. You could probably get two kneeboards out of that. You can have such a blank shipped most anywhere in the country (a couple of web sites advertised them).

One problem is that balsa can be quite uneven in its qualities. One plank can be extremely light and the next very heavy. Obviously you want to go as light as possible but also the lighter the balsa the less dense it is which means it is also much more fragile (you can easily dent it with pressure).

Being able to choose your planks from among many and then build your own blank from scratch allows you control over this problem, so I decided to do so in order to not only have control over the quality of the blank but also to be able to custom build it specifically for making a kneeboard. I was lucky in having good access to balsa planks here in San Diego at Frost Hardwood (total cost: about $150). A friend gave me the marine epoxy I used to glue it up with. You can use clamps (best) or just heavy weights to hold the planks together (sandwich them between two pine planks) .

The idea of rough shaping the planks before gluing them all up was my own idea. It would work just as well to glue up the blank without going through the initial rough shaping process. I was just a bit anxious to get started and it seemed like it would save me a bit of work in shaping the board as well as some glue! It worked out pretty well and I plan to stick with that method .

The tools I used are very basic. Hand saw. Block planes (3” and 7”). A Surform (same kind used in shaping foam boards). Small level. Sanding block and lots and lots of sandpaper! Definitely wear a dust mask as balsa dust is very fine, floats freely through the air and will get into and onto everything .

Like any project of this nature it is 10% inspiration and 90% perspiration! Hopefully the board will ride as nice as it looks .

[lowrider]

Very nice Bryan, it should look lovely when glassed.
Inspired me to give a thought to making one! I recall seeing a fish on here somewhere...

There's a guy here in Noosa, an American- Tom Wegener who is building longboards made from Pawlonia (spelling?), a Chinese timber that is beginning to be grown commercially as its very quick growing.

Apparently its closer grained or something therefore better to work with.
Might be worth checking out if you get keen enough to do another one.

cheers
Andy

[Bryan Jackson]

Yes, I found a web site about Paulownia (?) being grown in Australia but I couldn't find any for sale here in San Diego. Apparently it does have the same strength to weight ratio as does balsa (the best of all woods) and is much less expensive because it can be grown on farms.

Balsa only grows naturally in forests and, interestingly enough, is actually considered to be a weed! It grows quite rapidly in open forest spaces that have been cleared through either natural means (storm, fire, etc.) or by humans. It is important because it provides shade for other slower growing species of trees, protecting them from the strong sun which allows them to get established.

Balsa reaches maturity rather quickly and dies off soon after that. It must be harvested by the time it reaches something like seven years of age, otherwise the wood starts to lose its strength, rot and becomes useless. It is expensive mainly because it is labor intensive to harvest and get to market.

Paulownia is much less expensive since it can be raised on farms. I would definitely like to find some Paulownia. Since you are in Australia you could probably get some easier than you could get balsa.

[fooj]

Thanks for the info Bryan. I gotta see if I can get some Balsa locally, or something comparable.

[surfhorn]

Back in the 1950's -early 60's, surfers used to scavange balsa wood from surplus World War II naval life rafts. Balsa was used in the rafts for its floatation abilities.

The wood then would then be laminated together and shaped into boards.

[MTBarrels]

Re the polycarb and plywood sandwhich...(witch?)...

(wich)