Strong but not heavy
To hold the Sky Yurt up in the air, and to attach the awning for the workspace I was going to need a strong core structure. But the Sky Yurt itself could be made of much lighter structural materials. It only had to hold itself together, like a pop-up camping tent. I was driving into Willsboro one afternoon and saw a backyard trampoline with a kids low play tent stretched over tramp. I knew about trampolines from my trimaran sailing. A few people jumping on a trampoline generate a strong downward force that needs to be resisted by the frame. So trampoline frames are built to be very strong. .But they are also portable and are pretty light for the stresses they have to deal with.
Using the trampoline frame to hold up the Sky Yurt
For the next model I went hunting for circular rings. Found what I was looking for in a craft shop – those hardwood rings that are used for needlepoint work. I made a new balsa wood and plastic straw model, and I really liked the look and feel of it. I was ready to build my first prototype. Now I was getting into the real building project. My scare-level increased to the point where I thought I might need to start wearing a metaphorical diaper. I asked my friend Andy Wekin – he was an artist who had gone back to school to be an engineer and he came with his partners Otis and Ezra (more on this team later) – to be the consulting engineer.
Beginning to build the first prototype
I found a trampoline frame on Craig’s List and hauled it home. They are really available, sort of like old hot tubs and spas. They are in those class of things that at the time seem like a good idea, but they stop being used (you don’t want your kid to break her neck) and they take up space a lot of space in the outdoors. My friend Robin runs a preschool at a farm. They had a lot of PVC pipe that had been used in an irrigation project, and for a small donation I had my beams. I made hubs out of plywood and scrounged for PVC connectors that I could cut up and experiment with. I had SS wire from some of my old sailing rigs. Mostly I wanted to learn from this first structure -see if the basic engineering would work, where I would need extra support and how the Sky Yurt structure would interface with the trampoline frame. And it started out looking pretty promising.