Sunday, July 29, 2007


The benches are done and ready for the trip to the playa! There will be three of these surrounding the base of the tower.


With some help from David, I was able to to finalize the details for the shade cloth cover on the base. Pulling the cloth tight from tip to wide base allowed it to stretch out nicely between the cables. I added bamboo struts to spread the cables apart and used an 18" long piece to provide the articulation between the sections. The struts nock into the cable like an arrow into a bow string - then they're wrapped with inner-tube to keep them from slipping.

My to-do list is getting shorter! Now, on to those benches!

Saturday, July 28, 2007

Sunday, July 22, 2007

shade cloth

I was able to cut all the shade cloth for the main structure this weekend and begin to wrestle with the problem of attaching it.

I took the giant pieces of cloth (18' x 34') to my son's elementary school where they have a covered exterior basketball court. I stretched out the pieces and taped them to the floor - marked out the triangles using a single piece of rope with each side of the triangle marked out on it - then used a chalk line to snap a line that I could cut with a pair of scissors. With the help of my wife and son the whole thing was accomplished in a few hours.

I'm working with mounting a couple of the sections to the cables now, and as is usually the case when I'm treading new ground, something unexpected occurred - when I attached the shade cloth to the cables - the cables bowed. You can see it very clearly in the photo below. I've got an idea for bowing it back out that would utilize bamboo poles in compression using a tension connection of cord linked back to the cable. The cables need to be more or less straight for the panels to be articulating the way I imagined them. As it turns out - I think the poles may help the articulating panels work better. More as that progresses.

Sunday, July 15, 2007

shade structure

I made good progress on the shade structure this weekend. The support poles and cables are basically finished. Figuring out how to get the non- triangulated lines accurately located is the next problem to solve. I have an idea which also ties in to the problem of accurately cutting the triangular sections of shade cloth - the next big task.

I going to try using a low tech approach. I'll take a single piece of para-chord and mark off each leg of the triangle with a bit of tape - then all I need are two friends the hold the other corners and we'll have a precise outline of our triangle. At least that's the way I'm hoping it will work.

Instead of single poles and double guy wires I'm using double poles and a single guy wire. I really like the way the geometry relates to that of the tower - it seems to connect them together. The cool thing is, they actually don't touch at all - but pass through one another at the center and the perimeter.

I'm excited to see the affect adding the shade cloth will have although I'm not certain if I will be adding any to the top of the tower. I'm a little concerned about the wind resistance it will create.

Thursday, July 12, 2007

tower up II

I raised the tower last night after adjusting the guy wire lengths and will leave it up for a week or so and let the strong winds we've been seeing lately have their way with it. It wasn't nearly as scary this time and all went smoothly.

My back yard is proving to be a great place to work but a lousy place for photography! I apologize for the quality of the video - however it does give you a good sense of how well the gin pole is working.

Shade structure work begins tonite!

Monday, July 9, 2007

independence day part II

I'm calling Thursday, July 5th my personal independence day. I generally don't consider myself an independent person. I tend to want to do things in groups and rarely strike out solo for any adventure. One of the 10 guiding principles of Burning Man is "Radical Self-reliance" and I've somehow found myself getting pushed and pulled into this new area of self-development. It's not a bad thing but it is kind of scary.

By Thursday the 5th I'd managed to re-assemble the tower and gin pole with what I was hoping would be the final structural changes - the tower was ready for another raising attempt. So without much notice, I tried to gather a few friends and campmates to help with the task. Nearly everyone had prior commitments and I found myself alone at 7 p.m. waiting for the one person who was able to help. 7 turned into 7:30 and finally at 8 o'clock I realized I was on my own for this one.

I was torn - I really needed to find out if the modifications I'd made were going to work. I was leaving for a weekend on Orcas Island the next morning. Raising the tower is probably the most nerve-racking part of the process. The tower is under a severe amount of stress and having a few hands available to guide it up really helps. The new gin pole design incorporated a block and tackle that makes it physically possible for one person to raise the tower - but I would be risking a disaster if things started going sideways.

I decided to raise the tower just a little and see how it responded. With the end about seven feet off the ground I tied off the rope and walked around the tower giving it a thorough examination. The tower was pulling slightly to the right - but I wasn't able to find any loose connections - it just seemed to be a function of the tower's flexibility and the slight sloping angle of the base connection. There was no popping or cracking and besides the slight rightward bending everything seemed solid and stable. So I untied the rope and hoisted away. At a certain point the tower became very light and balanced and I was able to gently set it into its full upright position.

I stood there looking at the tower, my heart hammering in my chest, trying to detect any buckling or swaying - there was none. The tower was stable without the guy wires even in the light breeze of the evening. Eventually, as I became more confident that it wasn't going to come crashing down, I was able to get my camera out and take a few pictures.

When I went to attach the guy wires to their rebar stakes I discovered they were about three feet to long - I'd made the mistake of calculating their length from the 3d model. I hadn't planned on leaving the tower up while I was out of town anyway so with a little more calmness than during the raising I began to lower the tower back down. Immediately as I began, the gin pole base popped out of its pivot. After getting it back into place I lashed the gin pole feet to the pivot bolts and began again. This time the poles stayed in place and the tower lowered gently and silently back to the ground.

So the tower is now resting on its side in the back yard, awaiting the guy wire modifications and the next raising. I'm happy I was able to manage by myself - overcoming my fears of failure and disaster, being independent and self-reliant and all that - and I hope I don't have to do it that way again.

Thursday, July 5, 2007

independence day

Pictures from my independence day.

I'll talk about it later.

Monday, July 2, 2007


I was able to test some improvements to the structure this week that so far seem to be working out as expected. I reworked the connection between the vertical sections to take some of the strain off of the horizontal triangles and added an internal guy line that really helps support the tower during the lifting process.

I was also able to build and test the gin pole idea using the bottom 3 sections of the tower. It worked great as you will see in the video. No pops or cracks or undue bending - just smooth lifting force.

I'm hoping to get the top portions of the tower rebuilt this week and have another go at raising the full tower on the 4th or 5th.