no good yet

[Tballer2]

We had some high winds, windmill didn't move till about 30 mph wind gusts, then spun a little. Had to go to doctors, got home pretty late, saw the blades were bent back from the wind, one was up against the pole or tower. I took it down today and increased the angle on the blades, I put a 1/2" nut behind the bolts on leading edge to increase the angle 0of attack. It started raining so thats about all I could do, I am going to try to realign the ring gear it is off a little, which isn't helping either, thats all for now.

[dbcollen]

When you gear up, you multiply rpm, divide torque, and multiply bearing and gear losses. You will never see much output from that mill because you are losing all your power in the gearing. Windmill blades have near zero torque at zero rpm, so the forces of the wind just push the blades back untill it gets spinning and centrifugal force helps keep them straight. as the blades accelerate the apparent wind goes from the front wide face of the blade to the leading edge, which also reduces bend back forces.  Gearing up is bad, even well engineered oil lubed gear boxes suffer the same multiplication of losses when used to overdrive. This is why most small mills are direct driven to an alternator that is suited to low rpm. larger mills with pitch control can overcome the losses at startup by increasing the blade pitch to increase the torque. (which is also changing the apparent wind to the leading edge of the blades)

Dustin

[Tballer2]

`Thanks for the info, When I finaly decide to throw in the towel, which may be soon LOL, I may use the motor for an anchor winch on my boat, at least that way it won't be a total loss.

[bigkahoonaa]

Hi Tballer2:

I had a look at your pics.  Quite adventurous.  From my limited experience, I've always found that blade torque is inversely related to load.  The more current you draw, the harder it is to spin the blade.  Shorts in your lines will also make your blade hard to spin.  What kind of load do you have (batteries, lights)?  Have you tried to see if it will spin without load (i.e measuring open voltage)?  

Moe

[Flux]

Sadly he will never have got a load on it. Dustin is absolutely right, it needs precision engineering to get any improvement with gearing.

Normally you need to make such drastic changes to the blades to increase the starting torque that you end up with something that is no faster than the original high tsr prop.

Using odd motors as generators is not ideal, there are some that work fairly well and the wise guys on ebay have geared the price to milk those wanting them, they were scrap   price a few years ago.

Trying to adapt motors designed for very high speed is not likely to be effective even with decent blades. The problem is compounded by the fact that those who can't build an alternator generally can't manage better than pvc blades and these require even slower motors.

Much the same problem years ago, those stuck with car dynamos never got very far, it was only the few who could rewind things to lower speed that got any results, the conglomerations of lossy gears either never worked or had a short life.

Flux

[Tballer2]

I had no load on it, I was waiting for a decent wind to get it spinning so I could easily measure what  it was putting out, unfortunantly I never got a measurement from it. I heard we got some 30 mph winds coming again, I am going to try to set it up tommorrow morning again and see what happens. From what I have read and seen so far, the axil flux by far seems the way to go, these shortcuts just are more trouble than what there worth. The axil flux doesn't look hard to make at all, just mainly the expense of the copper wire and magnets. That was why I tried the 20 dollar motor, cheap and thought it would put out the amps,  just wasn't sure about the rpm.

[bigkahoonaa]

You should see something with no load.  I'm trying Hugh Piggott's 8 foot design.  You can get the plans from here Axial Flux plans.  But, don't be like me.  Follow the plans exactly.

[elvin1949]

Tballer2

  All is not lost. You can always drive that motor with a 5 horse Briggs for a backup.

  When the wind don't blow the batteries will still be hot.