Well,
I have it casted and it turned out fairly well with polyester resin...the top had a few holes, mainly about a half a dozen or so trapped air pockets which were at the surface. There was not a crack to be found anywhere. The trapped air pockest at the surface can easily be filled, they are only about 3/16 inch deep.....not very large in diameter.
The bottom of the stator came out smooth, no voids cracks....anything....perfect.
I followed the advice of the Dan's and Mr Piggot in both of their manuals when dealing with polyester; combining both ideas for this one casting ( pitching their manuals here, if you don't have them, and can afford them, then go ahead and spend the few dollars on them and be confident in what you will be doing!)
Things I would change if I were to wind another stator:
Don't do like me and wind it opposite of the wire travel as it goes around the center island. Look at the Dan's manual closely and see which way the individual is turning the coils winder and its direction of travel! I didn't !,
Here's what happened:
If you stand in front of the coil winder, as if you are watching someone winding a coil,with the crank handle facing you, I would be to your left and winding the coil in a clockwise direction,with the wire spooling off behind me, futher to your left. When this occurs, you end up having to bend the wire from the coil back sharply or make a very small radius as you make the connections around the center island....it would probably be best to wind them in a counterclockwise direction...it would make for a more streamline connection and less "figthing" of the connections, in the photo, you might not be able to see it, but the tails of the coils have to bend back in the opposite direction, as they are hooked up around the stator.
Second: Grease or use paste wax underneath the island center, and the outer surround too.....just go ahead and grease everything up as you assemble it.
I greased it up after I assembled the mold, and even caulked the inner and outer diameters so as not to get resin underneath these joints....well the resin got underneath it anyway, so I had to ruin the mold taking it apart..I used a caulk which was probably a window glazing caulk, thinking it would be good enough, but in retrospect, a good silicone caulk would have probably been better.....some of this might because of the pressure used, I used decking screws to anchor the lid on instead of C-clamps
It took just under a gallon of resin for this stator and about two 14oz bottles of talc, ( I could have used more talc) The resin came with two bottles of hardener, I used exactly half of what the mfg recommends.... I followed the very good advice in the manuals on this!
The coils all fit nicely, I had to pull the tape down very hard and push the smaller side of the coils in slightly with the palm of my hands to fit within the layout lines, but I used a piece of 3/4 inch plywood for the overall mold depth, which actually came out about .710 thick, this actually helped somewhat..I didn't have any of the "starts" to poke up through after casting...( this situation has haunted me before)
