These are pictures of some Dragonflys, Dragonfly clones, & associated projects. Probably most builders don't have digital cameras (or any cameras). At any rate, y'know, feedback is hard to get<-- hint.

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Eduardo Monzon's wind test site on the Chilean coast, near Arica (link in Spanish) Eduardo has problems with the local authorities who want a free piece of the action for permits. They did that to me in California too. Something needs to be done there, because they kill startups, which are hard enough anyhow, and everybody looses. Suggestions please contact Dragonflypower

This machine was erected on the Garcia river in Manchester, CA. It ran lights and radio for 2 large Geodesic domes, worked continually and was totally neglected for up to 2 years at a time. 4 blade designs are easy to balance, but not as strong as 3 blades. Four also produce more drag because they have more trailing edges.

An electric wheelbarrow built on a motorcycle rear fork. It only has one speed, the power is from a ford starter w/ a 1.25 inch v belt spindle pulley. The "Go" switch is a momentary button connected to a starter solenoid. The 10 inch driven pulley turns a jack shaft with the starters' bendix attached to the drive sprocket, so the wheelbarrow can be pushed foreward without disengaging the belt, but that makes it tricky going downhill with a load, so the left hand controls a hand brake to the motorcycle wheel. Two Jack shafts drive a chain & sprocket that turns the wheel. The fender hump in the middle isn't a problem and the big wheel will push 250 pounds over soft ground, 400+ over hard ground. More can be carried but balance becomes awkward, and a lot of weight overwhelms the brake. The small person is a Mendocino Pygmy placeing a spell on her moms' horse.

A power generating excercise bike, courtesy of Napoleon Molina.

This Dragonfly had a wooden feathering carriage as a test bed for attachment configurations of the spring, automatic field switch, and wiring. It worked fine but in the opinion of the builder, (me) it looked flaky, like a bunch of wood blocks, randomly glued and bolted together. Later designs used iron, because it looks more durable, but sealed Hardwoods will work as well. .

A turntable with modified brushes, and blade mount with adjustable pitch. My opinion is that both modifications look well done, but are unnecessary complications. For the pitch adjustment to be practical, the twist taper should be adjustable also. I've never had problems with the existing brush configuration, and it's much simpler. This photo was sent to me, I don't know where the machine is located.

This is one of the first ones I made. The long narrow vane responded slowly and wandered some. A more responsive tail has a vertical vane with a sloping front edge, like a sailboat jib. This machines' 6 foot blade was mounted directly on the alternator, but the pitch couldn't be cut shallow enough to match the rpms needed. At the time I chose to use a step up pulley to get the rpms, rather than a modified alternator, because I didn't know anything about wrapping field wire. Ed Lenz recommends making an alternator from plywood, to match the blades' power curve, a good idea if it doesn't overheat.

Maquina eolico "La Parina" y Napoleon Molina, with friends. Colombia.

Sometimes people are inspired to use big fan blades because the work of making them is already done. If you're planning this, I'd like to head you off: ---> My friend Aldrian did an excellent job on the frame, so I expect he won't tolerate that blade for long.

Fans are made to put energy into the air (a propeller), it's main regard to efficiency is the cost of production, so they work about 1/3 as well as one designed to pull energy out of the wind (a turbine). They're heavy, and metal fatigues, especially if they've been salvaged. This one looks about 3 or 4 feet across (less than 1/3rd the area needed for what appears to be a 35a delco) with a 14 inch drive pulley. The broad width of each individual blade puts the porosity ratio high so that most wind will go around the plane of the blades as though it were a solid disk, unless it turns slowly, so it looses efficency in higher wind. Small diameter, large pulley, no airfoil or twist taper, will put the output threshold above 20 mph. unless the field requirements are miniscule, but then the total output will be also. Aaaaah! don't do it!

This is a good bearing arrangement, though there's no mechanism for manual feathering. There's also no return spring, so it might get stuck in the feathered position till the wind pressure falls below the weight of the alternator, which is used here as a counterweight. This could save the machine in a squall, but finding the right weight so it doesn't shut down too soon or too late might take awhile. (math anyone?)

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