Brakedrum alternator construction

Full details of how to build a brakedrum alternator are available in my book Brakedrum Windmill Plans 2000 Edition

There is also some supplementary information on my update page

Below you can see parts for the brakedrum machines.  The six tabs welded to the axle tube are mounting lugs for the stator laminations.

Here is Wally Stahle of Future Electric Energy Co., San Luis Obispo CA winding coils for the stator.  On the right is the special former used for clamping the coils.  It has a sheet metal liner to give a smooth surface of exactly the correct radius.  The cardboard in the photo is being used to simulate the coils and create the correct radius while the liner is glued on.  I am grateful to Bob Budd who taught me that trick and has an excellent video for sale,

Here is Ian's daughter Rose Woofenden with the completed former, and on the right you can see Ron helping Bob Petersen of Kankakee IL clamping the coils down in epoxy.  I think Bob found my methods a little bit rough and ready compared to his own homebuilt 10kW machine, crafted with precision machine tools, but he did his best to humour me.

Below you can see the magnets going into the brakedrum.  Dan Whitney had the brakedrum skimmed out to fit the magnets in advance, and chose material for the shims so that the magnets would fit neatly.  The magnets are 3x2x1" ferrite blocks from wondermagnet

Below you can see the completed rotor and stator assemblies, and on the right is Brian Faley assembling them.

Below you can see the tail boom being welded to the brakedrum windmill yaw tube.  It is mounted on the side rather than the top, and we took great care to angle the hinge correctly.

Dan Whitney (below) did not have the pleasure of seeing his machine fly during the course but we were able to test the alternator and figure out the best coil connection pattern for his application.

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