6' wind gen for under $100.00

[christopher]

Finally got my G.E. fan motor conversion flying.  It all came togethr including tower and 10  T105 Trojan Batteries for under a $100.00.  This cost was for mag (12-1/2X2X1/4), welding rods, paint and guy wires.  Everything else was scrounged so it shows it can be done if you have the time and patience. Not much testing done yet, have seen a max of 260 watts at an approx 25 mph gusts, it seems to either have an early furling problem (fully furled 15 to 20 mph), or the tail is too small for the amount of offset I have on the blades. It seeks the wind, comes up to speed well but then turns out, loses power and seeks again over and over.  I do not think the blades are stalling as it will do the same into 18 volts as well as the 12.  Here are some pics:



Here are the blades before painting.  They are made from Alton's calculator from 4 X 10 fir with laments at the root for full width and drop.



This shows the windings I rewound at three phase, 12 wraps per coil, as much as I could fit in.



As this motor had bushing, I used the end plates and bearings from a jet pump which were a good fit.







I'm on a hillside and had to add this footing to even my guy wires.



I decided to chain drive the gen because I did not trust the weight of the blades on the bearings and end caps I used. It's a 36 to 30 gear ratio, as close to 1 to 1 I could get.





Hope all the pics are'nt a problem.

Christopher

[pyrocasto]

Good looking genny! Any specs?

[richhagen]

As the generator 'spins up' in the wind, the amount of force pushing back on the blades should increase.  This would effect the balance at which the blade lifts turning the blades out of the wind.  Basically, it seems to me that your tail is likely just a little too light.  Nice looking economical set up.  I like the use of the pump ends to facilitate the use of bearings.  I'm not sure how much loss there is in the chain drive, but you would have the option of optimizing the ratios for your conversion as well as potentially using a heavier bearing for the blades.  Looks nice, Rich Hagen

[harrie]

Looks great Chris, nice nose cone, props and tail. keep us informed on the pros and cons of the chain drive. Harrie

[Flux]

Nice job.

It sounds as though your tail is too small or the boom too short, The shape is nice but the area is not that large, I would be tempted to make the boom longer to see if this will keep it into the wind up to furling speed. If you have a free yaw bearing with ball races rather than pipe on pipe it makes things worse in this respect.

Flux

[Experimental]

     Hi Chris,

    Very nice job, all well done !!

    Now,build new bearing end plates, and get rid of the drive, maybe just add a thrust bearing to take the thrust load of the prop !! -- How do you lube the chain??

    Also like the tower -- what is the tower heigth??

    Judging by the vegetation I see, you aren,t from around here -(USA, Washington)

 Anyway, all very nice and let us know the final results -- really nice pictures!!

   Bill H......

[domwild]

Great pics! Have fun!

[christopher]

Thanks, all you guys for the nice replies and for putting up with all my questions over the past year.  I know now that these questions get asked over and over again.

I would especially like to thank the ones who have stuck with me.

As far as the chain drive goes, I know I am getting a late start-up, it will not self start before a 10 to 11 mph wind, but will keep going down to a 8 mph wind. The chain is not too noisy, quieter than I thought.  I have only greased it as it is all brass and stainless steel.  The tower is 36' tall, made up of 1-10' lenght of 3" pipe, 2-10' lenghts of 2" pipe and 1-10' lenght of 1 1/2" pipe.  I am about 15' above all obstructions.

Thanks for the info Flux.  The offset on the blades is 4", the tail is 3 square feet, the lenght from the tower to the tip of the tail is 3' when furled equal to the blade tips.

I am thinking about adding 12" to the lenght as this will be a lot easier than enlarging the tail.  Would you think this is in the ball park or I should add more or less?  Thanks for all your valued assistance over the past year.

Christopher

[Ungrounded Lightning Rod]

I concur with Rich And Flux.

 - It's furling too soon.

 - It's probably because the boom is too short or the tail too small, or both.  (That boom looks darned short for those blades.)

- The oscillation occurs because of the increased drag due to lift as the blade speeds up, combined with a lack of any fluid friction or other drag in the yaw bearing to damp it out.

Increase your tail length to hold it into the wind better and get your furling set right.  Then see if it still oscillates when the wind gets up to where it (properly) starts to furl.

At that point the gyroscopic action and/or blade drag may be enough to keep it from being a problem.  But if not, try putting a heavy grease in your yaw bearing or putting a short pipe-on-pipe section below it and heavy-grease that.  (Or cobble up something with an extra magnet or two and a piece of copper, to use eddy currents to damp the yaw.  B-)  )

[drdongle]

What did you use for the "nose cone"?

[christopher]

Hi Dr. D.   I started with a 1/4" plywood disc, built up with layers of 2' high density foam insullation, glued togther with contact cement.  Mounted in drill press and sanded to shape.  I then put a thin layer of body filler to seal, resanded and painted.  

Christopher

[kenputer]

That nose cone sort of reminds me of someone I used to know :-) And I liked it a lot also. Great job!

[ghurd]

It just looks cool!

Like a sports car kind of cool.

G-

[Flux]

Yes I think adding 12" would be quite useful.  It may be that you have some turbulence that you may have to live with. You may find that it runs smoothly in some winds and waggs in others, but an increase in length should help.

Flux

[FishbonzWV]

Great Job Christopher!

Looks good and I really like the resourcefulness for the free parts.

I think the high kick in speed is from cogging if those are bar mags without a skew, but you've got plenty of wind, right.

 I've seen your footing used for davits on a sailboat before. Lots of them available right after hurricanes. :-}  Speaking of that, what's your plan when one threatens...can you drop the tower easily?

If I ever sail past I'll keep an eye out for your genny and salute with a Kalik!

Bonz

[drdongle]

sounds like even I could make one of those!

[christopher]

just a sketch to show how i did my skew bering

[christopher]

Thanks Bonz. It is a salvaged boat davit. I also used the winch from this for the tower, so it only takes ten minutes with one other person to drop it.  The photo showing the rotor was before I skewed the mags, I had 2 and 1/2 ft. lbs. of torque before skewing.  Very little cogging after.  Thanks for the reply. Give me a shout if you are passing by Elbow Cay.

Christopher