Chambering Balsa

I’m shaping my first balsa board. When I bought the wood I didn’t know (rather think about) how much the wood can vary in weight. Although I go matched boards (they all weigh about the same) I don’t think I got the lightest (competition) wood out there. I’m considering chambering my board to lighten the load. Especially since I hear balsa likes to drink resin and I’m pretty much a hack in the glass shop as well. Anybody know what the expected weight of a 23"x10’ balsa board without chambering would be? How much of a diet can I put it on if I chamber. I wasn’t planning on any stringers (solid balsa). Would I need one if I hollow it out? What’s the best chambering method? Triangle cuts like trusses? You router it out? Can you help Jim?

The amount of weight saved is dependent on the weight of the wood and how gutsy the person chambering is. The savings is significant though. The best way, in my opinion, is with a drill and a large forsner bit which they carry at Home Depot.

Thanks Man. I’m going to the depot. Any rule of thumb about how much to take out to keep the strength? Any pattern you like?

Jeremy, Check out the posts by Jim Phillips and Paul Jensen in the archives. When I was doing mine I used the following guidlines: 1. Jim Phillips can get balsa guns down to almost the same weight as foam guns. Note: Exercise care with this guidline. He is an expert and we are not. 2. The Evolution site states that their balsas are 20% heavier than a regular foam board. 3. Another site I checked (can’t remember the address…sorry) the builder stated he could get 9’ to 10’ balsa longboards down to around 23# to 26#. In doing the chambers I used a brace and bit in combination with a router. As Greg mentions, some of this depends on how daring you are feeling. The problem, depends on the wood you are using. The pieces I was using differed in weight and hardness. Some sticks I had confidence in others I was nervious of. In any case, have fun. Oh, save the wood chips for the garden. Patrick

Thanks Bro! Got any photos of your chambered board?

Jeremy, There is a picture in the “Resource” section. It is board #578. Sorry for the quality. I’m not very good at this business of posting pictures. A site named has some nice pictures of balsa boards. In addition, you might find and interesting. Finally, Paul Jensen has a site called that has some beautiful pictures of wooden surfboards. Good luck. Patrick

Patrick - That is a great site. Chuck Basset and George Robinson, IMO are master craftsmen even if they don’t get much exposure.

I’ve seen Chuck Basset’s work at Bashams and I am IMPRESSED, but as far as George Robinson is concerned, I’ve know him for close to 30 years and he has very far to go to be in the realm of master craftsman. He just has an inate inability to use tools in a way to get a decent result. I glassed boards for him that were going to retailers that I knew and they were not happy with what was delivered to them. Unfortunately, he is a pentacostal lay minister and tosses that into the mix if your dissatisfied with what he gives you. Don’t mix religion with work!

If you’ve known him 30 years, you would know better. I stand corrected.

Jim, There is a rich guy that lives in south orange county, I think his name is Tom. He owns a drywall manufacturing company. He makes one of the nicest balsa blanks I have seen in a very unique way. He has basically had most the master shapers (Brewer, Velzy, Diff, etc…) make boards for his personal collection. Do you know who I’m talking about? Ever seen one of his blanks? Sluggo

It is Tom Keck that you speak of, he brought me one of George Robinsons “pre-chambered” balsa blanks that Dick Brewer had shaped a Buzzy Trent out of. I had to route out planks on each side of center and reskin the blank. The chambers were out of sequence with the ones around them and stuck up about a half inch higher. Tom has made a form for gluing balsa skins around it, with solid blocking at the nose and tail. If you look closely you can see the thin glue loine running down the center of the rail, it is an efficient way to use the wood to maximum. Tom is one hell of a good guy, he gave Pat Curren his 12" Makita Jointer/Planer and by talking to him you’d never know he was a gazillionaire

Jerry Kearns, who has the sicsticks site, has a massive board collection. Last year I made an 11’0" for him, it has a 1/2" redwood center stick, with 4 flairing curved redwoods coming off the center cut, from the nose. He liked the nose and tailblocks off the old Harbour Trestle Special, I still have some of the 12 pound density Clark sheet foam, so I did the same blocks for him (1" foam with a 1/8" redwood against the board). Top and bottom are the lightest Ice Blue tint, with a 1/16" dark blue resin pin on the top lap, just another day at Santas work shop