Author Topic: 18 foot duel rotor complete (Read 3539 times)

harrie · « **on:** March 24, 2006, 07:17:16 PM »

The following pictures are of my completed 18 foot duel rotor, with 16 " dia. magnet rotors. The blades are turning as these pictures were taken, so there is a little choppy distortion on the blades.

My first intent was to balance the blades when I got them on, but found that everything was Ok, I guess I got lucky. I did however balance each rotor, and blade hardware as it was fabricated, by puting the peices on the hub, and grinding the heavy sides. I think this is another reason why I think it is important to machine all the parts to tight fit on the hub. Of course, I realize that all of you do not have a machine lathe to do this, but if you can, its the way to go! On the test stand, I am afried to let it run very fast, so for now, I have it hooked to a 12 volt bat. I cant beleve how easy it turns, and puts amps into the bat, at only 15 to 20 Rpms. The wind here today, is little to none, and my 12 foot that is on a 60 foot tower, stops and starts, but the 18 foot just keeps pluging along, and does not stop. I shut it down once, thinking I had wired something wrong, and the battery was driving the turbine. The tilt so far seems like it will work Ok, but will not try and test it until I get it up on a solid tower. I think it is scary, and would be Ok with me if it never has to furl. The blade hardware, worked very well, and is very solid. By grabing one of the blades, and pulling in and out, I noticed quite a bit of movement between the rotors and the stator, which could only be a loose bearing. I thought I had the castle nut tight enough, but I guess not. I think I will shim out the gap more after seeing that, I would rather lose some power than have contact on the stator.

Great fun, Harrie

MelTx · « **Reply #1 on:** March 24, 2006, 01:03:40 PM »

Looking good Harrie ,I belive you got the hang of..

jlt · « **Reply #2 on:** March 24, 2006, 01:16:28 PM »

great job harrie. i like your tilt back. hoping it will work good for you .think i will try it on my 15 inch roter machine. i have two machines running,a 200 watt wincharger and a 8tf piggot. the two never point in exactly the direction. have changed the tail angel .but the side facing .is always a little off.if i make it track well in moderate winds . it is off by a lot before it starts turning. a does not start very well. a tilt back would solve that problem.keep up the good work.

fanman · « **Reply #3 on:** March 24, 2006, 06:14:56 PM »

harrie, harrie, harrie,

that machine looks great, im not real keen on the tilt back style governer, but hey i dont see any reason that it wouldnt work just fine, that blades are very nicely done, and a very nice blade center too. ya know that litle trailer test tower will blow over in a good wind, therea alot of force on those big blades,again harrie great job now lets put it up and guite playing around.

rotornuts · « **Reply #4 on:** March 24, 2006, 06:29:45 PM »

I'm very impressed Harrie. Top notch work and I love the tilt back furl.

Mike

harrie · « **Reply #5 on:** March 24, 2006, 06:32:19 PM »

Hi Fanman, ya your right, I am afried it will blow over,but we still have too much snow to put it on the tower,and I couldnt wait. ha. I do kind of wish I had built the stator 5/8 Inch thick instead of 1/2", so I could have had more wraps of wire. I think 100 RPM to get 48 is a little fast, like Hugh P said a cut in of 80 would be better. I guess we will see! I think the next one I do, will be on a shaft with bearings rather than using a spindle. I think one should be able to use a hydraulic disc brake on the shaft that would engage to slow the turbin rather than a furling mechcinism. I know there is alot of toque expecially with the large props, but wireing for high voltage with low RPMs, I cant see why it wouldnt work? Maybe Im wrong, and maybe it has already been tryed. Again, I think it also depends on the force of wind in your area.

Thanks for the comments Guys, Harrie

rpcancun · « **Reply #6 on:** March 24, 2006, 07:16:37 PM »

The brake may work, but your asking for trouble....

Constant maintenance, you have to maintain the brake pads.
How will you know when the pads need to be changed?
If the pads wear out and you dont catch it, you may have alot of probs..

use your imagination.....

Just my 2 cents......

JohnC · « **Reply #7 on:** March 24, 2006, 07:17:35 PM »

Enjoy the life you just created, great one! What's it set to furl at?

harrie · « **Reply #8 on:** March 24, 2006, 08:08:16 PM »

Hi Rp. There again, I think it depends on the average wind speed of your area, How long does the brake rotors on the front of your car or truck last? I think there would be alot more ware on a veichle than there would be on a turbine? and I think the machanical assyembly would be simple and reliable with very little maintance.Anyway Just a thought, and being Im retired I have plenty of time to tinker. ha.

willib · « **Reply #9 on:** March 24, 2006, 09:01:23 PM »

Harrie did you taper the blades?

they look more tapered than in this photo

of is it just the camera angle ?

harrie · « **Reply #10 on:** March 24, 2006, 09:55:52 PM »

No, didnt change anything, Willib. the cameras never do show things like they really are.I do know that I would not change anything, they work great.

Experimental · « **Reply #11 on:** March 24, 2006, 10:41:08 PM »

Very nice Harrie, and a well done,

I hope to build another soon, but at the moment I have a cabin project to complete, so the real fun will have to wait....

Wishing you, lots of wind and a successful test session -- Well done, Bill H...

tecker · « **Reply #12 on:** March 25, 2006, 04:14:29 AM »

Heat and vibration is a rotor killer

harrie · « **Reply #13 on:** March 25, 2006, 07:02:41 AM »

Hi John. I wont do any testing and seting of the furl until I get it on a stable tower, so will need to post about that later.

smidy · « **Reply #14 on:** March 25, 2006, 07:11:31 AM »

Hi harrie, very nice work! about your brake idea i think its better to go for a drumbrake, simply because its need lower hydralicpressure for the same brakeforce and its better wetherprof, and if you take a rearbrake from a car you also have the parkingbrake wich can be used like a parkingbrake simply by taking a wire down to ground and from there you can brake and park your mill.

keep up the good work!!

rpcancun · « **Reply #15 on:** March 25, 2006, 07:20:32 AM »

Good question harry.

but how will your system know when and how much pressure to apply to your brake?

I have been working for over 10 years on a self regulated blade feathering

system until a few weeks ago the machining was too complex.....then one night

(which I didn't sleep) the most simple method dawned on me!! (I'M VERY EXCITED)

my blades will automatically feather themselves into the wind maintaining one speed...always, and they dont have to have airfoils like a prop they are flat

and 3 times as wide, why?, with this speed control I can harness the wind far

better than a standard prop design, the larger the square footage of blade area

exposed to the wind the more torque I will have, kind of like a sail boat

the larger the sail the more wind I will harness...that and the fact my best friend

is a graduate of MIT in mechanical engineering helps.

Also looking at the in labor involved in axial stators and rotors I have decided to go horizontal kind of like a store bought fan, the coils will be placed on the outside of lets say a 2' diameter pvc tube ( or bigger) then the mags are placed on a steel tube inside, now the wind will cool the coils since they are outside

as oposed to a fiberglass pancake that locks the heat in, but we will not know how

it will work till I actually do it I am in prototype mode as we speak...wish me luck!

rpcancun · « **Reply #16 on:** March 25, 2006, 07:28:33 AM »

Good question harry.

but how will your system know when and how much pressure to apply to your brake?

I have been working for over 10 years on a self regulated blade feathering

system until a few weeks ago the machining was too complex.....then one night

(which I didn't sleep) the most simple method dawned on me!! (I'M VERY EXCITED)

my blades will automatically feather themselves into the wind maintaining one speed...always, and they dont have to have airfoils like a prop they are flat

and 3 times as wide, why?, with this speed control I can harness the wind far

better than a standard prop design, the larger the square footage of blade area

exposed to the wind the more torque I will have, kind of like a sail boat

the larger the sail the more wind I will harness...that and the fact my best friend

is a graduate of MIT in mechanical engineering helps.

Also looking at the in labor involved in axial stators and rotors I have decided to go horizontal kind of like a store bought fan, the coils will be placed on the outside of lets say a 2' diameter pvc tube ( or bigger) then the mags are placed on a steel tube inside, now the wind will cool the coils since they are outside

as oposed to a fiberglass pancake that locks the heat in, but we will not know how

it will work till I actually do it I am in prototype mode as we speak...wish me luck!

Shadow · « **Reply #17 on:** March 25, 2006, 08:40:02 AM »

Very nice job Harrie! I like the tilt back system and hope to try one sometime. Do you know the average windspeed for your area? As for the 'play' in your wheel bearing, I use synthetic grease and lots of it,I have a tool for packing bearings with grease.It consists of two discs with the bearing sandwiched in between.Then you use your grease gun and the grease is forced into the bearing equally and evenly.I tighten the castle nut while turning the rotor slowly until it becomes quite stiff, then back it off a couple nothches on the castle nut and drop the cotter pin in. Then put more grease in the dust cap and tap it on with a rubber mallet.It works for me, I do vehicles, boat trailer,etc the same way. Happy flying!

Nando · « **Reply #18 on:** March 25, 2006, 09:08:03 AM »

Harrie:

Your BRAGGING - RIGHTS - have been increased 1000 times.

GOOD JOB.

Nando

willib · « **Reply #19 on:** March 25, 2006, 11:18:16 AM »

Have you got any diagrams?

harrie · « **Reply #20 on:** March 25, 2006, 11:56:03 AM »

Hey RP, sounds like a good plan to me. Im not quite sure I understand the flat blade thing tho.How wide is this stator tube going to be? will it be as wide as the coils are, or will you have the coils skewed in a longer tube with a center rotor with the mags skewed in the opposeite direction on a longer rotor? Dont know if this would work or not, but Im always comming up with crazy ideas, and most of them dont work.Ha.Anyway, keep us posted on your project!

harrie · « **Reply #21 on:** March 25, 2006, 11:59:27 AM »

Good point smidy, you may be right. anyway, lots of fun, Harrie

harrie · « **Reply #22 on:** March 25, 2006, 12:07:13 PM »

Hi Shadow, Yes, I think I will do that. My son tells me that also to use synthetic grease, that could be some of the problem, cause I used some real light grease, and not much of it. I did plan on doing it better before I put it on the tower, and will need to get a packing tool. Thanks

willib · « **Reply #23 on:** March 25, 2006, 08:06:51 PM »

harrie i have thought about a mechanical brake also , it could be as simple as a cable with a lever hooked to the disk brake piston mechanism, pull the cable and stop the turbine..release the cable and the piston retracts .

rpcancun · « **Reply #24 on:** March 28, 2006, 12:17:16 AM »

Hi Rp. There again, I think it depends on the average wind speed of your area, How long does the brake rotors on the front of your car or truck last? I think there would be alot more ware on a veichle than there would be on a turbine? and I think the machanical assyembly would be simple and reliable with very little maintance.Anyway Just a thought, and being Im retired I have plenty of time to tinker. ha.

well I would have to disagree on that one, when you use your brakes how long

does it take to stop....a few seconds??

Now imagine your windmill under 6 hrs of of heavy winds, that brake will

be constantly on for 6 hrs your also talking one brake, a vehicle has 4

how long will the brakes last on your car going down a mountain for 6 hrs

with your foot constantly pressing last?

If memory serves some brakes when they get hot enough from riding them

glaze over, then the pad is so hard it doesnt work any more.....

Just my 2 cents.....

SmoggyTurnip · « **Reply #25 on:** March 28, 2006, 07:51:55 AM »

Very nice - get that thing up in the air!

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Author Topic: 18 foot duel rotor complete (Read 3539 times)