Monday, April 23, 2007

2 sections tall

I was able to assemble a second section to the tower mock-up this weekend as well as implement a few of the structural recommendations made by my friend Dihong Shao.

The inner tube lashing technique continues to look promising - it has the marvelous ability to keep the connection tight even while being wrenched around. I'll probably end up doubling the tubes where they connect the vertical sections together - just for the redundancy. I've added two tension lines to each of the square plan sections. These prevent the squares from deforming into diamonds. I also realized that these tension lines can be added to all the squares before the trip to the Playa - greatly reducing the amount of work that will have to be done upon arrival!

I managed to break one of the vertical poles while attaching the second section - this was before any tensioning and bowing. The pole broke right on one of the nodal ridges - which makes me think it must have been rotten or already cracked. Now I test each pole for structural flaws before I use it!

The second image is a view from the bottom of the first section as it lays on its side. I love the graphic geometry of this point of view.

Tuesday, April 17, 2007

a sunny weekend!

I finally had a sunny weekend on Vashon! Just in time for a visit from my good friend John Boylan, writer, editor, community activist and occasional fire and piro whirler, and Christine Kristen, aka LadyBee, curator of art for Burning Man. Christine was in town for a lecture on the Art of Burning Man at the Youngstown Cultural Center and was able to stop by Vashon Island for a visit. I attended the lecture last evening and was wowed by images of Burning Man art projects from 1995 to present. Very inspiring stuff!

On the construction front I was able to do a little more experimentation on the compression detail as well as getting a good start on another section for the tower mock up. I've figured out an easy way of building the vertical sections. I build the geometry unfolded on the ground, then stand the assembly up, moving the corners into the proper position and tying the last two connections.

Sunday, April 8, 2007

compression in tension

I built an idea for the compression strut connection today that bows the vertical struts quite nicely! It has the added benefits of being easy to install and very resource efficient.

The end in the picture is a simple loop of rope lashed to the end of the compression strut with 1/8th inch paracord. There's a little friction tape on the bamboo end to keep things from slipping around. This end is tied on first. The other side uses a similar arrangement of rope lashed to the pole end but instead of a loop I use a trucker's hitch that bows the verticals as it's tightened.

The poles were relatively easy to bend even though they're a couple of feet shorter than they'll be in the final version. They're pushed out about 6" on each side.

Wednesday, April 4, 2007


I'd like to have some benches for people to sit on around the base of the tower. Here are a couple of ideas I've generated. They'd be very easy to build from tam vong - I could use screws to attach the pieces. They're about 2 feet wide and 6 or 7 feet long. I'll need to make 4 of them. The curving members are slats, everything else is made from poles.

Monday, April 2, 2007

next year . . .

I had this idea for an enclosed womb-like structure built of vertical bamboo poles lashed together with split bamboo horizontals. Large enough for a dozen people or so to fit inside.

Sunday, April 1, 2007

10 foot poles

I finally had a little time this afternoon to work on the tower. Andy Royer supplied me with a bundle of 10' long x 1 1/4' diameter poles and I've begun assembling them into the basic geometry for one of the tower sections. The proportions are all off but the basic connections are valid. I used pieces of road bike inner tubes {from my friends at the bike shop) to lash all the connections. Its seems to be working well so far - they're easy to put on but a little hard on the hands - I'll have to find some thin leather gloves, I'll probably end up wrapping the connection points with friction tape like last year. It will make it a lot easier to keep the joints aligned. It's funny how this looks so much like the wooden dowel model!

I'm working on another compression detail that is all bamboo. The end will be shaped like a fork that would fit over the crossing point of the verticals. Images to come, then I'll mock it up full size on the built section.