This is my build of the TowerSimple XL 3D printer based on the original PrintrBot Simple and designed by Almus Yang.
Alums Yang's Instructables page https://www.instructables.com/id/Building-a-3D-Printer-Under-200/
Parts List and Marlin firmware https://practicalprojects.weebly.com/towersimplexl.html
Fan Duct https://www.thingiverse.com/thing:839620
Rigid Shaft Coupler https://www.thingiverse.com/thing:533928