"..I've seen fiber laminations used just on each end of the stack for insulation. They are sometimes slightly oversized to be sure to cover the edges of the laminations..."
Anyone that is seriously interested in insulating stators can go to the powercroco and powerditto pages and see some of the masters at work. With or without the translations by google, it is wonderful stuff to look at. A couple of examples, the first two using some kind of paper or thin sheet fibreglass on a bare, uncoated, stator:
12N10P4035 Scorpion V1 - http://www.scorpion.powercroco.de/12...corpionG2.html
German to English translation - http://tinyurl.com/d36sokb
12N10P4030 Speedscorpion - http://www.scorpion.powercroco.de/12...dscorpion.html
German to English translation - http://tinyurl.com/c2uwc3e
This one shows how to make the fibreglas end caps they use on the ends of some of the larger bare stators:
Isolating a stator pack - http://www.powerditto.de/statorisolieren.html
German to English translation - http://tinyurl.com/9pl927w
I don't speak or read German, the google translations border on unintelligible at times, as always the pictures are worth many, many words.
Here the starting pages for all of that:
If anyone can decipher the brand names and North American sources for some of the exotic insulating materials in use there (papers, sheet fibreglas, etc.) it would be wonderful. I will personally designate that person a Hero of Motor Rewinding and do all I can to make it a sticky thread!