window lamp-shade

I want a simple window lamp shade. So i designed one that I was happy with. It is designed so that you just click the ribs together with the baseplate and support ring. Plate nr2 needs to be printed 3 times as a total of 15st of that kind are needed. The ribs on plate nr3 needs 5st which are distributed evenly around the baseplate as it provides the position for the support ring. Plate nr4 (m10x1.5 bolt) is optional. I made it just to secure my lamp holder to the base plate. But it works just as well without