SRSG motor modification

["Garth van Sittert" <garth-at-mediasupplies.co.za> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

I recently modified a 1/4 HP capacitor start; approx. 2800 rpm motor to make it
synchronous.  I ground two flats across the 'dead poles' on the armature
according to motor1.gif etc...  However I must have done something wrong as it
is not synchronous.  Using a neon as a timing light the blur only comes into
focus a couple of seconds after power off when it is coasting down.
 
The motor only has 16 poles so I was't 100% sure on the modification compared
to the instructions referenced above which I have seen mentioned a couple of
times before on this list.  The starter windings seemed to ocupy much more pole
space than the ones shown in the diagrams and are interwoven with run windings
as well, so I thought rather than grind too much.....