My first

[jaskiainen]

Hi Otherpowers!

It's finally come together. My first genny.

A dual rotor 12 magnets per rotor 9 coils three phase system.

Magnets were 12mm dia 3mm thick N52. Quite small ones?

Many people here said that why to built up a genny this size?

My answer is simpe: Because it's just for learning the basics right now.

I'm glad i went that way. Mistakes were made and if it would have been

a big 500W genny it would have been expensive try out!

This weekend was quite windy here and i HAD to go and put my genny up in the air.

Weathercast said 25-40 km/h. Trees were more like horizontal than vertical position.

I'm sorry to say that even if people here told me to take a lot of pictures i

have only few to show you.

This is how it looked this morning.

But lets start from the beginning.

First i made magnet rotors. Here i'm glueing them in place.

Then i made a coil winder.

A bolt with two washers and a piece of pipe between them.

Then i wind my coils. First ones were 93 rounds of 0.4mm dia magnet wire.

Start up speed with them was too low so i made another set with 110 rounds/coil.

Here i'm glueing them on my paper template.

All them in place.

Here is where i didn't take any pictures. I cast my stator in resin

and made the rest of the metal work. Crappy made and i've been thinking to

make a better one with some improvements.

At this point i made a test drive with my friends lathe and got 2.2 amps

in to a battery at about 1200 rpm. Stat up speed was around 600 rpm.

Next i made some PVC pipe blades but they were way too slow for 600 rpm.

No pictures of them either. I throwed them in to a trash can and started

to carve wooden blades.

Next photo taken with blades painted.

I wanted to built also a furling system even if this small genny might not need one.

Every part in it is aluminium. I can't say it's the best material for it but

it's free for me so i gave it a go. Offset is around 75mm.

I made it all based on Piggot's book and guessing. It came out pretty good.

This picture shows when it starts to furl around 1 amp.

And fully furled around 1.7 amps.

Even if it furled maybe a bit early the winds were so hard that i saw 2.41 A peak!

I left the genny up in the air and will go to check it on next weekend.

I'm hoping that it will still be in one piece.

Big thanks goes to everyone who have helped me out to understand basics and formulas.

Do i even need to finger point the gurus here out?

Special thanks goes to Ghurd for all the help within this project.

You opened my eyes for a thing or two.

[Janne]

Hello!

Thaks for sharing the project. Looks like a nice learnign project, with some useable output too.

[Airstream]

I get a strong 'something is sooo familiar about that' but I've never seen one like it - very nice effort & execution. ...Thanks for sharing... .

Have you tried it into a 2$V or 48V battery bank?

What is the blade length?

[jaskiainen]

Hi Airstream!

I've made it for 12 volts. I made the magnet rotors first and because of

my desire to make everything as small as possible they came up 74mm dia.

That caused a problem with my coils. The first one fit perfectly in place,

but when i added that 17 rounds per coil i had to squeeze them a bit of

an elliptical shape to make them fit.

I could have made them thicker, but that 5mm airgap (4mm) stator is quite

as much as it can be for my tiny magnets.

I kind of wonder that there could have even 10 rounds more per coil.

Ofcourse it adds some resistance to coils, but even with this (3.5 ohms per phase)

it does more power than i hoped for.

Well the space is that much of a limit that i don't think i can make it fit anymore.

And the answer to your second question:

Prop is now 82 cm dia (32.3 inches). Original prop was 90 cm dia, but i cut

the blades a bit to get them faster. There seems to be some spare to cut them

even shorter? TSR is 6 or 7. Can't remember it now.

As i told before the genny itself is crappy made wich i think causes some problem.

The start up speed is now around 500-550 rpm. And it goes there with slow enough

wind, but when it rises to around 600-650 rpm it starts to shake and rumble.

That made me thinking about it might have something to do with the "poor" output

in low winds. It stays nicely spinning with about 20 mA output, but when it

goes a bit higher it kind of slows down. I think because of vibration?

If it spins a bit higher 800-> rpm it stays spinning nicely until the wind calms.

I hoped around 2 Ah per day for it with normal winds and it might can go there

and even higher if i get rid of that rumble and make better blades.

[TomW]

jaskiainen;

Nice project. Sometimes I think "smaller" is not always "easier". Looks very nice and I like the flashy paint job. Mine are pretty boring.

Those Doc Wattsons sure are nice for monitoring what has been going through the system. Much better than having to camp out by the meters anyway.

Tom

[jaskiainen]

Thanks Tom!

I have to agree. Smaller is much more difficulty to do. Thats why the vibration.

My girlfriend is kind of "orange" and she gave me no choice for colouring it. =)

[Flux]

Glad it worked out ok in the end. I am sure you will have learned a lot and it's so much more satisfying when it works out.

Flux

[oztules]

Jaskiainen

Excellent stuff!

You came, you saw... and you conquered....

It's nice to see it flying, and putting out some power too.

You have learned a lot, met some great people, and had some fun to boot.

It don't get better then that.

Thanks for sharing that with us, and don't forget the pictures with the next one...... there's always a next one... just a little bigger, a little better, and a little more powerful and a little bit bigger grin when the amp meter flutters higher...

..........oztules

[ghurd]

Looks great!

G-

[luv2weld]

Great work!!! Really good paint job!!!

Did you remember to rebalance the blades when you cut

them down??? That might explain the vibration and rumble.

Thanks for sharing it with us.

Ralph

[jaskiainen]

Thanks Ralph!

Yes i balanced them again. The main problem i think is the axle.

It might be a little bit curved or otherwise out of balance.

I'll make new for it when i have some spare time in hand.