Drive Sprockets:

Almost forgot about these.  I had some free time after dinner.

Instead of broaching (read: I don't have one) or filing or hacksawing :-O  I decided to plunge a 0.187" end mill to make a "mouse hole" approximation of a key slot in the tapered bore of the drive sprocket.

Tried to take a pic to show the sprocket and the shaft, but the quality control inspector kept getting in my way.  His name is Warrior ( Warry ) and he apparently likes the nice crisp corner.  He is diabetic and almost died when he was a kitty, he might have a little brain damage as he 14 but still acts like a kitten.  He is super affectionate.

"It's mine now"

Not sure what that look means, I'll take it as approval.

The shaft is tapered with a woodruff key, the lock nut and washer hold the whole mess together.  The lock nut is is one of those where the nut is crimped slightly to distort it.  It is not going anywhere, this shaft used to hold the whole wheel on in the wheelchair application.

Now on to the chains, battery plate, and so on.

I'm considering using a piece of plywood as a "temporary" plate across the back of the frame to hold the batteries and wiring.  Eventually I'll make one out of sheet steel as it will also form part of the rear mower discharge.  It will allow me to test the drive mechanism enough to be sure the input design parameters are correct.