I am constructing a very basic miniature generator (25mm diameter), the rotor has 8 bar magnets, and there will be the same number of coils, wired appropriately, in the stator.
I understand that the magnitude of the induced current is much bigger with iron cores to the copper coils. However, I have only very basic materials. The cores will be short lengths of iron bar, similar dimension to the bar magnets, cut lengthwise to minimise the air-gap.
QUESTION 1: Can I wind the copper wire directly onto the iron bars? Would this cause some kind of interference?
QUESTION 2: The bar magnets are very powerful Neodymium type. If the air gap between rotor and iron cores of stator is minimal, I don't see what prevents the alternate "N/S" polarity of the magnets basically locking onto the iron cores and preventing it from rotating!