Maybe take your large hole saw and saw into the plastic piece a few mm to make a reference circle on a drill press.  Then bolt the plastic part to the hole saw in the reference circle then put it in your lathe and turn the inside diameter out to the exact size for the commutator using test fits.  That should insure concentricity and size.  If it is secure and accurate enough it could be used to turn the inside of the commutator.

greybeardmike

Hello All,

Thanks Mike!

Yes, there are many ways to solve this issue...now, removing the choke on lathe and replacing it by a single plate will not work - on an easy replacement deal- on my arrangement, simply because the Chuck is mounted on lathe with a specific center thread...plus three bolts set exactly at 120 degrees...
It is easier to make a piece that has a nice diameter center shaft, then chuck it.
By the way, thanks for correcting my wrong spelling on "jig" NOT "gig" like I said before.
Other issue I just found out...I need a bigger Vise-grip for the CNC...mine just opens max to 4 inches...not to six.
I have a huge rotating vise-grip that I bought long time ago...but it is too "bulky" and heavy to mount it on CNC.

The rectification on the outer diameter just took out from 79mm to 78.29 mm, meaning just reduced by 0.7 mm approximately:


Anyways, thanks, I will keep looking through all my scrap metal and my big motors fans (great idea! because they are concave)

Regards

Ufopolitics

Dear Ufopolitics,
I greatly appreciate your work and tenacity. I was wondering if you could test another way to obtain the segments, with less effort and with lower risks of segment deformation. I suggest you test separately, on another piece of copper, a cutting by chemical etching or electrolysis.
P.S. Please, if you have time, explain to me, in a few words, why you abandoned the asymmetric generator approach. I was very excited by your approach and had even started to make my own generator, then the Figuera generator appeared.
Best regards, from Romania,
Sorin