This part is crucial. The amount of power you generate pretty much depends on two things: the speed of the wind, and number of coils. Other factors play in, but these are the big ones. You have not control over the wind, though, so make this step count. I highly recommend using thinner gauge wire than I did. I used 28, and got decent results, but I think 36 gauge will blow the doors off of my current set up. It's all about the number of wraps. The 36 gauge stuff is harder to find, so you can make do with thicker stuff--just be aware of the cost of doing so.
Here's how to go about it.
- use a dowel for the big spool of wire
- put bobbin on an awl, then insert the awl into variable speed drill
- leave 10 - 15 cm hanging when you start. You'll need these to make connections later.
- wind the first wrap slowly or by hand. If you're using thin stuff, do it by hand.
- you can increase speed thereafter. Again, be gentle if you have the thin wire.
- go back and forth, try not to cross, be neat.
- if using thin wire, be careful:
- in case of breakage, use a lighter to burn off the enamel that insulates the wire
- tie the pieces back together tightly
- it doesn't hurt to check the repaired connection with multimeter
- once finished, tape down the coil.
- leave 10 - 15 cm on the outside, too
- burn off about 1 - 2 cm worth of the enamel and the end of each coil with a lighter (just be careful with thin stuff, since it will burn up really quickly--a quick pass with the flame should suffice). Use fine sandpaper to take off anything that stays on.