Bamboo Projects
I worked on the projects below while interning at the Black Range Lodge in Kingston, NM during the fall and winter of 2002-2003. Thanks to Pete Fust and Tom Lander for providing copious bamboo-working advice, whether I asked for it or not.
Display Rack for the Lobby of the Black Range Lodge
When I had expressed an interest in building something with bamboo, Pete Fust suggested
a book display rack for the lobby. It was something the Lodge had needed for quite some
time, since the books that they sell were normally stacked on top of the lobby desk in
such a way that made it difficult to browse through them. Pete gave me a general idea
of what he wanted, and I took it from there.
Most of the pieces are of the tropical bambusa tuldoides, while the top two shelves (or troughs) are from a piece of bambusa oldhami split in half. There are a few bits of temperate bamboo in there, too. All of the joints are secured with copper wire that was purchased from a copper mine liquidation auction. The decorative scrolls at the ends of the copper wire eliminate exposed burrs by hiding the cut wire ends.
The bottom platform is constructed like a primitive raft using several 6-foot long pieces of tuldoides, each about 1.25 inches in diameter. In the first iteration the pieces were woven together with copper wire in 5 places along their length. This method did not tighten the pieces together well enough to straighten out the more troublesome bends in the bamboo, leaving large heaves in the surface of the platform. I eventually took it apart to try a different approach.
With all of the pieces separated I first sanded them down to make them look nicer (a step I skipped with the first iteration). I then made a drill jig with a 6-foot long piece of wood trim so that I could drill a .25 inch hole, a few inches from each and in the middle, through each piece of bamboo but the front and back pieces. I then took 3 pieces of copper wire and bent them in half around the front piece; I threaded the two ends of each wire through the corresponding holes in the drilled bamboo pieces (the jig ensured that the holes would line up). The wire ends were then spread to wrap around the back piece, then twisted with pliers to tighten everything up.
I made the guard rail (the piece that keeps the books from sliding off the platform) with three bamboo poles that were each about .75 inch in diameter. I wove them together with copper wire in the same way that I did the first version of the platform, leaving long wire tails which I then used to secure the guard rail to the front of the platform.
The 2 uprights for the top shelves are from a very stout piece of tuldoides about 1.5 inch in diameter, secured to the existing desk with wood screws. I spaced them so that they would line up with the thick nodes of the trough pieces to guarantee a strong attachment point. I reinforced each trough by wiring a narrow bamboo pole to their undersides, threading the wire through the nodes for strength. The troughs are attached to the front side of the uprights (more wire) while the book support rails are wired to the back of the uprights. Since the uprights are vertical, this allows the books to lean back at an angle and stay in place.
Folding Tabletop Display Racks
Free-standing, Collapsible Display Rack
Didgeridoo
Bill and Veronique are neighbors of the Lodge who split their time between Kingston and the
San Francisco area. Veronique makes and sells bamboo didgeridoos, and she is also a
didgeridoo instructor. Before they left Kingston for the winter she was able to give me
the 5-minute lowdown on how she makes them (as well as how to play).
Pete and I dug through his stockpile of bamboo from San Diego and found a big piece of bambusa oldhami. I quickly made several mistakes, the biggest one being that I started the mouthpiece at the wrong end (it should go on the end that was closest to the ground because the bamboo is thicker down there).
I went back and found another, better piece of oldhami. I used a hand saw and cut the end that would become the mouthpiece just above the node, being careful to first make a shallow cut around the circumference to avoid tearing up the outer fibers. Not sure how long I was going to make the final product, I left the other end alone. Each node has a septum that separates the bamboo's internal chambers, and the easiest way to remove them is to knock them out with a piece of rebar (the steel rods used for reinforcing concrete). The texture of the rebar also works well as a rasp to further wear away each septum. I made sure not to remove too much material from the mouthpiece end, since my mental picture of Veronique's didgeridoo was fading. The plan was to leave the hole small and sneak it out until it fit comfortably.
I used a belt sander (the stand-up kind) to roughly round off the outside of the mouthpiece, then used a knife to carve the inside. As I worked I kept blowing into it to see how it felt, and the starchy powder on the inner surface of the bamboo kept flying around and into my mouth. Ptooey. I decided to let the mouthpiece wait until I did a little roto-rooter work. I used some twisted copper wire to make a flexible shaft to put in the cordless drill, then put a folded-over piece of 60-grit sandpaper through the slot in the end. I fed the whole arrangement into the wide end of the future didgeridoo, then worked it in and out as I ran the drill. I had to slow the drill down when more than half of the shaft was outside because it would flop around uncontrollably and try to remove my head (note to self: use a stiffer flexible shaft next time). A couple of pieces of sandpaper later and the inside of the bamboo was as smooth as, well, the outside.
With the inside cleaned out I could get back to work on the mouthpiece. I quit with the knife to avoid drastic material removal, and switched to 60-grit sandpaper wrapped around a .75-inch diameter piece of bamboo. That worked well for making the hole almost perfectly round as well as for making a radius from the inside to the outside. I used sandpaper in my hand to radius the outside of the mouthpiece. My final mouthpiece is slightly oval, 1 inch wide in one direction and 1.063 inch in the other, with a smooth continuous radius from the inside to the outside (resembling half of a toroid for you geeks out there). The thickness of the mouthpiece (that is, the distance along the axis from the end surface to where the inside diameter opens up again) is about half an inch.
At this point the mouthpiece felt pretty good, but I could still only get a weak phhlpppppt to come out. I kept blowing, trying different lip pressures, positions, humming pitches, but it sounded awful. After about 10 minutes of this, though, a low rumble emanated from the didgeridoo. It only lasted a few seconds, but I knew that was the sound that I was looking for. I determined that the piece was a little too long for me to play well; the natural frequency of the tube was too low for my lips to flap around at for more than a few seconds. I cut off 9.5 inches so that the didgeridoo ended between two nodes, where the inside diameter was largest. I blew some more and bwoowwwooooowwwwwp I was rattling windows!
The final length of the didgeridoo is 57 inches, the inside dimension at the end is an oval 2.25 by 1.875 inches, and the wall thickness at the end varies between .125 and .2 inches. I finished the didgeridoo by sanding from 60-grit to 220-grit. Then I used a propane torch to darken it, followed by more 220-grit sanding to remove the singed surface. I applied 2 coats of BioShield linseed oil over 2 days, then let it sit for a day before polishing it with carnauba wax. I had fun walking around saying, "I'm going to wax my didgeridoo, if ya know what I mean - wink wink."