When I built prototypes of my invention (A No-Friction Bicycle Light Generator) before mass manufacturing, I need to test different kinds of coil to fit the product, so I made this coil maker (DIY winding machine). It is easy to be made, low cost and simple.
Link: A No-Friction Bicycle Light Generator
Link (webpage for this winding machine): DIY Hand-Driller Coil Winding Machine with Digital Counter
Step 1: Step2
Full view. You can get the pedometer on ebay for few dollars. There are many kinds of pedometer on market, in my mind, the cheaper one is better for building this winding machine. The magnet and reed switch can be bought as door alarm switch set in hardware shop. A old hand-driller.
Hand-driller's handle turning once, the coil will turning about 3.5 turns. So if the digital counter showed 100, the coil will be 350 turns. Each hand-driller may be in different rate, just test it before use it.
A no-friction bicycle lights dynamo
Step 2: 3
Each time the magnet on handle passes (not touch) the reed switch, the padometer's figure go up 1. The handle turns 100 times, the padometer should show "100". Hold a button on pedometer to go back to zero.
Step 3: Step3
Step 4: Step4
How the padometer works? Each time your body jumps, a metal hammer inside pedometer jumps once and touch a point (as a jump switch), send a electrical puls to counter, screen will show figure up "1". Take out the metal hammer, Lead 2 wires out from the jump switch to the reed switch.
Step 5: 5