At first for testing I jammed a steel rod into the lawn, and tied a pool pole onto it. I then climbed on a garden bench holding the fully assembled generator and stuck it into the top. Quite amazing I didn't injure myself.
While at one of the many engineering firms I visited I saw a 40mm 6 metre galvanised steel pole which had been lying around for a few years. I bought it for R180, and hammered 30cm of 38mm OD pipe into the end, which was the same diameter as the bottom of the bracket. I needed to heat the pipe and hit it hard with a four pounder, so it is jammed in good and solid.
A 0.5 metre long section of 32mm steel pipe fitted loosely into this, so I tack welded some blobs onto the lower bit to make it a tighter fit, and put a small bolt through the upper bit (matching holes in the bracket) to keep it in place. A washer cut from a 38mm aliminium curtain rod went in between the two 38mm pipes to make it turn a bit more easily. This may get crushed after a while, but even then the smear of aliminium (aloominum to our transatlantic friends) on the steel should make it rotate a bit more smoothly. I will also cover this all in grease before final assembly - or perhaps motorbike chain lube, which is waxy and so will be less likely to melt and drip away in the sun.
Now the problem was how to get it up.
I had seen winch systems with multiple steel cables and a gin pole, but that seemed complicated, and inappropriate for suburbia. I was worried about the pole taking the weight while being winched up from horizontal.
So the solution was to insert the generator into the end of the pipe without the blades and vane, and then to lift it onto a roller I made, by climbing on the faithful garden bench.
Then I climbed onto the roof and bolted on the hub and blades, and slipped on the vane. Note how the vane can rotate, but cannot touch the turbine blades
|Then I could push the pole up on the roller until it was vertical. Four 0.5 metre sections of 12mm threaded rod through the wall and some plates made from 40mm x 3mm flat iron bar held it in place once up. Some rubber car parts (as used on the roller above), and high density foam pads were added to hopefully absorb any vibration.|
|After a day of watching it I got nervous about metal fatigue, as the pole flexed quite a bit in the gusts. So I bought some 3mm steel cable, and ran it from a U bolt about 1.5m from the top of the pole to a raw bolt hook in the wall. Bicycle inner tube stops it from slipping down the pole, and a turnbuckle allows the tension to be tightended up. I added two more cable stays in a simlar way. One of them is attached to a 3 metre steel angle bar bolted to the wall, protruding by 1.5 metres.|
The angle iron was not strong enough, and would flex in gusts, so I ran another steel cable from the end down to the ground, attached to a hook I made from 8mm threaded rod. I set this hook in concrete poured into some drainiage pipe about half a metre long. The 8mm rod was not strong enough, so started to straighten and the concrete was simply lifted out of the ground.
So next I used 12mm threaded rod to make a hook. The rod goes under the path foundation, and is set in concrete. Hopefully that will be strong enough!
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Please bear in large bits of metal high above your head are dangerous, and safety precautions should always be observed.