However, having an excellent MacDonald style teacher in the school can look a bit like one can 'do the technique'. Nili's directions are precise and efficient, and we went through a lot of 'traditional' approaches like chair work, table work, hands on the back of a chair, monkey, lunge and finally the whispered aah.
Just watching Nili made it easy to give myself directions and keep myself up, the increased amount of 'uptime' might have led to the bit of discomfort between my shoulder blades. Or maybe just my bad use while taming a beast, namely a biggish tensegrity sphere.
I found in a cheap shop decorative bamboo struts with a nice dark red colour, together with some Sisal garden string. I build a lot of 6-strut symmetrical tensegrities lately, with a variety of connection methods and tension elements, so I started off with 50 cm rods and about 120 cm string. Sawing the grooves with the Dremel becomes more and more routine, although I find myself often crouched over the work piece.
I experimented with tying the strings to the rod, and making loops with knots to slide the ends through. This would save me sawing 60 grooves into the 30 elements, for the prize of 120 knots. A lot of repetitive activity, a great challenge to consider how to do it easiest. I was eager enough to prepare all elements before the assembly, a strategy I changed soon.
Some of the loops were too big, there wasn't enough tension on the strings, and the ends could slide around. The beautiful idea of easy reusability didn't work out. Back to grooves. The next attempt used sisal strings, but as some of it ripped too easy under tension I went back to nylon line.
I cut the strings so that they had nearly no slack - this might work with more elastic strings, but after about 15 struts it became obvious that it rather break than bend into a sphere. As there is no way of lengthening too short strings, the next set of strings needed preparing. To break the monotony of preparing everything at once, I prepared 5 struts at a time (there's six building stages requiring each time 5 struts).
The first two attempts were still too long, and I waited a day without doing anything before I went with the final approach. The water balloons I used to prevent the strings from sliding were easier to attach than the rubber ring wrapping I used most of time. Unfortunately, they came as easily of again.
The youtube video that inspired me in first place shows an assembly within about five minutes. I spend already the third afternoon and still wasn't sure if everything would fall into place. As the waterballoon failed as security, I looped the string once around the strut before using a rubber band wrapper. I must have started building a sphere at least a dozen times, I know now how to connect the elements with maybe referring to one of the models. I wouldn't be surprised to rediscover the build pattern as weaving pattern.
The skewer model gained stability after stage 4, it get itself balanced on five struts as dome. I got fairly confident when I managed to move the model from its gymball 'mould' onto its own feet. The sculpture rolled in elliptical shape on the floor, I leaned with my body against it to attach the remaining struts. I assembled the final five struts as a pentagon, and carefully slid it into the still wobbly dome.
The pentagon needed 10 connections, after attaching half of them I could turn the model around and do the last connections. I even dared to leave them unsecured. The model flattened still a bit, so I removed some of rubber wrappers and looped previously unlooped connections, decreasing the overall string length slightly thus increasing the tension.
I wouldn't roll it downhill now, but it hangs nicely on a single hook on the wall. Tuning was fairly easy, so I might remove the remaining security rubbers for an overall fine tuning. For now, I rather keep it untouched for some time to see whether it tends to undo itself.
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