Spider Coupling - Printrbot Simple Metal

thingiverse

Drop in replacement spider coupling for Printrbot Simple Metal. My Simple Metal came with a flexible helical coupling for the Z axis that would stretch or compress during a print, making the Z axis very inaccurate, and causing uneven layers. After finding out that a flexible helical coupling on the Simple Metal is used for the wrong layout, as it should not have vertical load on the coupler, people recommended a spider coupling instead, as it can support vertical load while still allowing twist compression. This is that outcome - to test this theory I designed and 3D printed the coupling using PLA and the spider with NinjaFlex-SemiFlex to allow for flexibility. After installing the new coupling, new prints where coming out better than expected, Z axis based walls were smooth to the touch unlike with the helical coupling. Well worth the time and effort of upgrading the Simple Metal. Instructions Print bottom and top couplers at 100% infill using rigid filament (i.e. PLA) Print spider at 20% infill using flexiable filament (i.e. NinjaFlex-SemiFlex)