I am still a kid at heart, had designed & 3d printed several mobile & tablet stands, to use it for chat or as lamp, but the problem was that there was no ease in assembling them, it required either tools or the parts would break, even it was difficult to reuse parts to make new designs, but finally with Clickaloo parts I was able to deal with all issues.
Please download following 2 parts from Clickaloo website, as it showed issues after uploading
1) 90DFA-I [90° Double Fold Angle - Inner].STL
2) 90DFA-O [90° Double Fold Angle - Outer].STL
For other configurations, you need other parts, I have not discussed, but hope you can make out.