[pmb1010]

Here are a couple pictures of the failure area on the motor.
It's literally split in half.
I put a red box around the area thats common to both halves.

It's only about 1/8", with maybe 3 or 4 1/4" ribs of whatever the material is - zinc or aluminum. In my opinion, that is woefully inadequate.

What I think happened is the wind would cycle the dish up & down, just enough to stress the area shown. Just like bending a paperclip back & forth, eventually it stress fails and breaks.

When it warms up (it's still 20 degrees here, but at least the sun was shining) I'll remove the motor from the 6 foot dish and put the halves back together to see if things could be stregthened, perhaps by drilling the base and bolting on a steel support plate with a dozen small pan head screws.