Unfortunately I don't have that many photos from the first construction of the stator for the "Nerdiskerator". (I will add new ones as soon as I have built the second version) Back then, when I cast epoxy into the coils in the stator, I worked with epoxy for the third time in my life. That's what my table looked like, and especially my hands and gloves. So I didn't want to touch my camera so much. : D
In the photo you can see the twelve wound coil cores, which were cast with epoxy in the stator shell. So that they stayed in place for the time of assembly, I first fixed each coil with a screw.
These screw holes could also be used later to expand the generator coils with an iron core. However, because of the resulting strong cogging torques (the magnets of the rotor always turn over the coil cores) I wouldn't use these iron cores at WinDIY. But if you later want to use the "Nerdiskerator", for example in combination with a water turbine (which should have significantly more initial torque), you could increase the energy yield with the help of the iron cores. :)
In the video you can see the first tentative turns of the "Nerdiskerator" prototype. the two rotor disks are each held by a ball bearing.