Hi Ghurd,
the failure was a combination, both caused by the disk material, (Paneling)
The paneling I used is the cheepo photo stuff, I am not even sure if there is any wood in it. My mistake was not roughing up the smooth photo side before gluing the pvc to it. the hot glue did not adhere to the round center ring on the smooth side and the force allowed the pipe to slide which in turn ripped the upper paneling.
I looked at a bunch of designs from picoturbines to Making a simple Savonius wind turbine by Lance Turner and then looked at what I had available for parts and this is what I came up with.
I am rather impressed with how easily it turns that little motor and lights that led, Almost burned it out yesterday. I think I might build another one just slightly differently.
I would like to use the same setup only larger diameter lightweight pipe and possibly use your full disks. I think I will use thicker material and rout the roters into a groove on the disk. I will also have to either find larger bearings and use 1/2" rod or use a center support with another bearing. The through rod works very well as a clamp to hold the pipe in place. I would rather stick with the bearings I have but 5/16" isn't very big.