Camp Elsewhere's Tensegrity Shade Structures
The idea behind a tensegrity structure is that the solid members are loaded under pure compression with ropes or cables providing all the tension. This allows them to be very strong while using a minimum amount of materials. The first of these tensegrity shade structures was built and used at Burning Man in 1998. In 1999, we redesigned them and made a bunch more. They work well for Burning Man because they are:
1) cheap to build,
2) fairly easy to transport,
3) fast and easy to set up,
4) nice and cool with maximum airflow, and
5) best of all for the playa, they are pretty much indestructible.
A bonus is that they are more minimalist, unique, and, in our humble opinion, more attractive than the sea of white pvc and blue tarp shanty structures which blanket Black Rock City. The downsides are:
1) they have a fairly big footprint for the amount of shade they provide so they may not work if you are camping in a crowded area.
2) as currently used they are not intended to block the wind or rain at all, they are for shade when it is nice and hot, although with the addition of more walls, they could provide some wind protection, and
3) idiots trip on ropes.
You can make structures like these with all sorts of variations in size and geometry which will all work just fine. Here is what you need to buy or steal to build one like ours.
Three 8 foot beams. These can be any material that is light, stiff, and can be easily drilled. We used cheap 2x3 lumber, but aluminum, steel or pvc pipe would probably work provided they are stiff and strong enough. Your mileage may vary.
A whole crapload of rope, at least 200 feet and more like 250 feet, depending on how efficient you are with cutting and tying knots. We use truck rope, that black and orange stuff, because it is cheap, very very strong, is weather resistant, and does not stretch. Downside is that it does not knot very easily. You can get them in 100 foot rolls at hardware stores. I usually use 1/2" because I like overkill, but you can probably get away with smaller. Do not burn this stuff, at least not anywhere near me, as it is plastic and will give off nasty fumes which I do not want to breathe. Any other rope that does not stretch too much should work fine. Steel cable would kick ass. One of our people made a structure using detachable rope hardware which made set up and take down a snap. Go nuts.
6 pieces of rebar. At least 2 feet long and 3/8" diameter and I personally like 3 ft x 1/2 inch cuz that's the kind of guy I am. Do not attempt to put up one of these structures with tent stakes or even with wimpy rebar. You will end up being a sad panda.
Fabric for shade - We used white cotton cloth custom sewn for our structures with many, many, many grommets. One triangular piece for the top and one rectangular piece for a wall which could be moved around. Our fabric was pretty sturdy in strong wind, but we always took it down during major windstorms. If you intend to leave your shade material mounted in major storms then you should think about some very heavy duty grommets or webbing or other suitably strong attachment method. Recently, we have been using old sails lying over the top of our structures and staked directly into the ground. This is very strong and provides a lot of shade and decent wind protection, as well.
That's it - that's all the materials you need!
Tools you will need to build
Drill and drill bits
Maybe a lighter to melt off plastic rope ends.
A couple of big pieces of pipe, about 3 feet long each and big enough to slip over your rebar.
Tools you will need to set up
Sledgehammer - everyone should own at least one big ass sledgehammer.
How to make the thing
I am not going to go through how to tie knots and loops and such because I don't know much about this myself and there is no one correct way to tie these things together. Do it however it works for you. I find that figure-8 knots work well for the permanent loops at the ends of the anchoring ropes. If you don't know how to make a figure 8 knot ask a friend who rockclimbs.
Step 1: Basically, just drill some holes sideways though the beam at the top and bottom big enough for your rope to go through. I used one hole at the bottom and two at the top (one for the top rope and one for the anchor ropes). The first structure used 1 inch eye screws in the ends but this is just something else to fail. Holes are better. Lookee at Diagram 1
Step 2: Then lay the beams out on the ground and tie it all together with loops at the end of the anchoring ropes. You may want to make a few of the anchoring ropes with adjustable loops/knots (e.g. a trucker's hitch) to make adjustments to the structure. Lookee at Diagram 2
There are only two different lengths of rope you need to remember.
Top ropes = 14 feet
Anchoring ropes = 10 feet 7 inches
These lengths are based on 8 foot beams, a 14 foot radius hexagon footprint, and the beams ending up at 60 degrees from horizontal and are the theoretical point to point distances in the final geometry. In practice they end up being a little shorter because the holes in the beams where the ropes are attached are not at the exact ends. As with every thing else, you can vary the geometry however you like, but found that these measurements provide a nice symmetrical small to medium sized structure that can fit about a half dozen people under it comfortably.
Basically, the tops of the three beams are connected in a triangle 14 feet on a side. And each of the three beams has 4 anchoring ropes coming off of it, two from the top and two from the bottom with a loop at the end of each.
Step 3: Bend your rebar. Stick a rebar into a pipe with about 10 inches of rebar protruding. Slip the other pipe over the protruding rebar leaving a few inches of rebar visible. Bend the top 6 inches back so it ends up looking like a candy cane. With 1/2 inch rebar this will not be easy. Have some friends stand on the pipe covering the long section of rebar or stick it in a huge vice. Do not hurt yourself doing this and do not sue me. Lookee at Diagram 3
Setting Up 1: Precise Method (need only 2 people, maybe 1 if you are desperate and have no friends)
1. Lay out a hexagon on the ground which is 14 feet in radius, 14 feet on a side. You can do this more easily by tying yourself a piece of rope with two loops 14 feet apart and use it with a couple of pieces of rebar like a big compass.
a) mark a center and draw a big 14' radius circle
b) pick a starting point on the circle and then use the 14' rope to find your other points along the hexagon. Lookee at Diagram 4
2. Hammer in your rebar at the six points but not all the way in - allow enough room to slip your anchor loops onto the candy cane sections.
3. Lay out your beams with tops in toward the center of the circle and bottoms out
4. Have a friend hold up one of the beams in close to its final position and attach its anchor loops and hammer the 2 rebar most of the way in (leave a little bit out in case you need to change something). Your other two beams will be all over the place now.
5. Have your pal hold up the 2nd beam and attach and hammer in the ropes from this one. Things will look a bit better now.
6. Continue on and do the 3rd beam.
7. If everything looks good. Hammer the rebar in so they are flush with the ground.
8. There will probably be some looseness in the structure. Adjust the knots so that everything is taut. There should be very little to no slack in any of the ropes. The structure should be rock solid now.
9. Attach whatever shade material you have fashioned.
Setting Up 2: Easy Method (need 4 people - works remarkably well)
1. Get three people to hold up the beams in more or less the final configuration (leaning away from each other about 60 deg from horizontal with the top triangle as taut as possible
2. Run around and hammer the 6 rebars into the ground, anchoring the 12 anchor ropes to the ground so that the structure is nice and taut and not too crooked.
3. Adjust or tighten any of the individual ropes as needed.
4. Attach shade material.
It's a good idea to practice putting one up near your home.
Structure test in Santa Cruz
Shade material test in Santa Cruz
Here are pics from Camp Elsewhere - Burning Man 1999 showing the shade structures under construction and being used.
Logan finishes her structure (layout of beams and ropes are shown clearly and labeled)
A bare structure in the background (ignore the choad blocking the view)
Jila attaches her shade material
Easy livin on the playa
Blowin in the wind (and Tammy with her birds)
The structures are strong enough to support a hammock.
Here is a similar structure from BM 99 that some people built using nothing but giant logs and ropes. This thing was completely indestructible and very cool.
Big shout outs to Elsewhere campers Layla, Logan, and Jila who put a lot of time and effort into the design and building of these structures.
Big ups to Jon Luini, Logan, jD, and Lettuce for providing all the photos. Diagrams are by me.
e-mail dan and include the "nospam" characters
Copyright 2001-2004 Clownland Enterprises, Inc. and Camp Elsewhere, Ltd.