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Dodgeman

Newbie

Joined: 19/07/2008
Location: United States
Posts: 33

Posted: 01:45am 09 Sep 2008

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Howdy Asvin,

I do hope that I am helping you with my comments and suggestions, and not making your experiments more difficult.

I dont know if you have seen what I am doing with my mill in my post here, but I would like you to see it if you have not.
Heres is the link to mine.

I will be testing it soon.
I am still debating a furling assembley but have yet to attempt to built it.

I think your 4:1 ratio could be a little hard to start,I am guessing this because mine is 2.4:1 with ball bearings in both the motor and on the driveshaft, with chian drive and it is quite a bit more difficult to rotate by hand than the earlier direct drive version was.
Maybe wider blades would provide the extra torque needed to get it turning? or maybe 6 blades? either of those suggestions will slow your mill some, and add weight, but both will provide more surface area to grab wind better.

Keep at it, and never get discouraged by setbacks.
Edited by Dodgeman 2008-09-10

asvin bahadur

Newbie

Joined: 29/07/2008
Location: Mauritius
Posts: 21

Posted: 05:07am 09 Sep 2008

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hi

sending you some more pictures of the drive shaft and the engine.

thanks

asvin.b

Jarbar
Senior Member

Joined: 03/02/2008
Location: Australia
Posts: 225

Posted: 06:22am 09 Sep 2008

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Hello Asvin,
well done with your attempts at getting it up and running.My observations are that the main shaft would run better on needle bearings that you may get to fit the casting.The shaft looks to be approx OD 25 mm or 1 inch so a suitable OD needle bearing should be easy to find even if you need to loctite them in.By then turning the diameter of the shaft to a smaller ID size to suit the nearest fitting needle bearings.The reduction in friction would be significant.And then trying the smaller gear on the shaft as the driving gear as opposed to the largest.It looks closer to a 2 to 1 ratio.Or just try the smaller gear first.Then the bearings.Only 997 ideas to go.

Anthony.

"Creativity is detirmined by the way you hold your tounge".My Father
"Your generation will have to correct the problems made by mine".My Grandfather.

asvin bahadur

Newbie

Joined: 29/07/2008
Location: Mauritius
Posts: 21

Posted: 06:54am 09 Sep 2008

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hi anthony,

thanks for your post.
this is my planning for the next couple of weeks.

first i am going to cut three more blades (4 feet) and add them to my existing one (3 feet).

then i will try to drive the engine directly and check out the voltage. after which i will try to get another bigger gear and replace the one on the dc motor head.

will keep you guys updated. thanks for the tips....

asvin.b

asvin bahadur

Newbie

Joined: 29/07/2008
Location: Mauritius
Posts: 21

Posted: 04:39pm 15 Sep 2008

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hi everyone,

so how was your weekend? mine was not too bad, i have been busy,ah yes with the windturbine again. as mentioned earlier, i managed to make 3 more blades and added them to my exising 3 blades plus i connected the blades directly to the DC motors.

the new set of blades are 4 feet long as compared to the previous set which are now 2.5 feet.

i had to modify the hubs to accomodate the extra blades.

the combination of short and long blades really work well. i could not believe it when just soon after i added the head of the wind turbine on the tower, it started to spin and never stopped, this is great.

then i connected the wind turbine to my multimeter and yes it was disappointing to see that it only showed 3.2 volts althought the windturbine was spinning really fast.

well 3.2 volts is not that great and don't think i can do anyhing much with it apart from connecting some LEDs
in parallel for fun.

i guess i am left with three choices;
1. work on gearing up
2. change the dc motor
3. stick with solar panels.

here are some more pictures.

for now, its goodnight from me.

this is a picture of the DC motor with the small gear, that was used earlier.

asvin.b

absinthe
Newbie

Joined: 07/09/2008
Location:
Posts: 10

Posted: 12:40pm 28 Sep 2008

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if your running it direct you want less blades and that will get your rpm up.. try with just the 3 longer blades.. or even 2 blade setup for a high TSR

wind-pirate

Senior Member

Joined: 01/02/2007
Location: Canada
Posts: 101

Posted: 01:57am 29 Sep 2008

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Hi Folks
I have one treadmill motor too...
They are not that great for wind generators. Mine is 3 h.p 120 volts d.c. in order to get 12+ volts 6amps it needs to turn at least 1,200 r.p.m.'s. "
"Checked with a drillpress".

We felt (Ken And I) we could do better so we went to a truck alternator 24 volts 200 amps. rewired it to wye.
That lower the cut in to about 700 r.p.m's. It also lowered the output too. We now get 12+ volts and have seen 75 amps. we ran this with a 4 blade prop. Geared 3.5 to 1:. It was belt driven "automotive multigrove" We used a 12 volt regulator from a 100 amp mopar. It ran all last winter 2006/2007 in a fly in construction camp. We have no pictures. "NO" cameras allowed in camp.

Ron

THE Pirate.
stealing wind & solar energy is fun

asvin bahadur

Newbie

Joined: 29/07/2008
Location: Mauritius
Posts: 21

Posted: 04:46am 29 Sep 2008

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hi there absinthe,

thanks for the advise, i will have a go this coming week end. i will try with three blades (4 feet)and see whether it does make any different. i don't have a taco- meter but i guess the voltage will increase. so i can monitor any changes with my multimeter.

I am wondering, whether it will turn in small wind!!!!
As mentioned earlier, with a six blades (combination of small and long blades) it turned in even a small breeze and would never stopped.

thanks, will report back again when i try it.

Cheers.
Edited by asvin bahadur 2008-09-30

asvin.b

asvin bahadur

Newbie

Joined: 29/07/2008
Location: Mauritius
Posts: 21

Posted: 09:18am 06 Oct 2008

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hi again,

as promised, i have tried to compare the different between both sets of blades. 1st set is of 2.5 feet long and the 2nd set is 3.5 feet.

well here are the results:

By combining both sets together (6 blades), the voltage i got (direct drive) was a maximum of 5.2 volts.

after removing the shorter blades (now 3 blades), the reading reached a maximum 6.1 volts and average being 5 to 5.8 volts which are better than previous results.

it was very windy on Saturday at my place, and the three long blades turned with much ease without stopping.

the only problem now is that the poles/ tower shake a lot, even the concrete base that i have made tend to move. With high wind, i was afraid that it may caused damages to the blades and the engine. the steel wires could not even prevent the poles from shaking.

i am sure that many of you will agree that by making your own wind turbine you are encounter with many problems and once a problem is solved, other problems cropped up. now i have to rework on my tower.

may i conclude by saying that the longer the blades are, the more voltage i will get. in which case, if i intend to use this DC motor (direct drive), then i will need longer blades to get more than 12 V.

my calculation says that in my case, i will need blades of around 8 - 9 feet long which means a taller tower.

any comments please!!!!

cheers.

Edited by asvin bahadur 2008-10-07

asvin.b

GWatPE

Senior Member

Joined: 01/09/2006
Location: Australia
Posts: 2127

Posted: 12:21pm 06 Oct 2008

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longer blades will usually slow the windmill and reduce the output voltage.

Gordon.

become more energy aware

vimal
Newbie

Joined: 17/08/2009
Location:
Posts: 2

Posted: 08:01pm 19 Aug 2009

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hi asvin,i am happy to hear that you are building a wind turbine.in fact i live in mauritius too.i am on the way building mine too.i got a motor like yours and another ametek 38vdc which i bought off ebay.i have not yet tried my wind gen with the motor like you have but i think that with the gearing system which i used,it should work fine.if ever you are still working on your wind turbine,just let me know.we can meet and discuss abt it.hope you get my email and reply me as soon as possible.see ya

vimal
Newbie

Joined: 17/08/2009
Location:
Posts: 2

Posted: 08:08pm 19 Aug 2009

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by the way,my email add is : coolbuoy_3@hotmail.com

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