I wouldn’t recommend drilling through unreinforced bamboo. Since bamboo’s strength is longitudinal, with almost no cross-grain stability, a hole can lead to a lengthwise crack that could cause failure. If it maintains its integrity, bamboo will flex a lot without failure. I employ two methods to overcome this problem—lashing and reinforcement. As you see in the masthead photo, my halyard tackle (okay, it’s just a bronze ring, but what the heck), is lashed in place. This is best done on the opposite side of a node—the rigid portion seen as a ring separating the hollow sections—because it will provide a friction point and stop for your lashing. Of course, any good lashing that is pulled toward the bottom—the larger diameter part of the culm—will automatically tighten as it does so.

 The second method—reinforcement—I have done two ways. In the mast base photos you will note I have added a bamboo collar to both reinforce that section and have a place for screw-mounting hardware. The collar is made from a little larger diameter section of this culm that has been split to fit over the section, then glued and itself reinforced with two thin bronze rods wrapped around it and secured in place.

The hardware screws act in shear—which means they are pulled sideways instead of straight out—and just barely penetrate the mast itself. It’s not the strongest arrangement, but more than adequate for this application. If a stronger mount where needed, the collar could be made of wood. The point is to avoid drilling holes in the unreinforced spar or mast itself. Which leads to:

The second reinforcement method I use, seen in the boom and spar photos—the insertion of solid wood pieces into the culm. The sprit spar end uses a hardwood dowel deeply inserted and glued in place. The plug is drilled to accept the snotter rope. The boom end also has a wood plug, but I chose to cut it flush. This, too, has a hole drilled through the plug through which my outhaul passes. Note in both cases, holes are through the wood, not the bamboo alone, and stress is in shear, or pulling in-line with the spar.
Now, the advantages: this stuff is cheap, even if you have it shipped to you. Considering that it’s already shaped and requires only minimal work to put it to use, it’s much cheaper than building your own spars.

Bamboo’s very light and very strong for its weight. Again, from The Bamboo Fencer: “The poles are 2" in diameter, they are first cut and fully dried, cured, and polished. They are stiffer than Sked 80 1.25" aluminum or 1.5" dia. Sked 40 aluminum often used on Junk Schooners. The maximum bow on a 21 foot pole is 3" or less.” Not bad for grass, huh. 

Being hollow, bamboo floats as long as you haven’t punched holes through it for wiring, which leads to another benefit—you could punch small holes with a rebar or other long rod and pull wiring for a masthead light. The light mount could take advantage of the hollow you leave for it at top, and the battery could be mounted within a similar hollow at the foot. Add a small switch in the lower side and plug the top and bottom wire holes with sealant, and you have lights with which to awe your friends.

As for looks, I have sanded my nodes smooth and varnished all my spars, painted the boom end as you see, and it makes for very nice looking rigging. Many spars turned out of lumber look better painted, but bamboo has a beauty that needs to be seen.

When selecting bamboo, consider the flex of the spar and know that the material will flex quite a bit without breaking. If in doubt, once you have discussed your choice with a dealer, order material that may be a little larger in diameter than you think you need. Think of it like reefing—if you think about reefing under sailing—then reef. Also buy longer sections than you need so you can trim the culm to length yourself. Once cut, treat the ends with a sealant like epoxy, varnish or some other product to keep bugs out of it. If you get green bamboo, know that it could lose up to 20 percent of its diameter as it cures, which takes about three to four months. Dry bamboo standing on end in the shade—you could hang it in a tree if you wanted. But store bamboo horizontally and out of the weather and sun, even if treated. I keep my rig hanging in my garage where it gets plenty of ventilation.

The photos I have here are of my sharpie. I’m restoring my E.M. White-style canoe and will definitely use bamboo for the new rigging. I’ll also use a bamboo pole for my push-pull tiller and a pushpole. There’s a lot of value and uses in bamboo, which, as you know, is just a grass. A grass on steroids, that is!

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