This is a grip made for the rift s and quest that simulates the Valve Index knuckles control, that means that you can let the controller go and it won't fall. Inspired by the MAMUT grip for the original Rift
You will need a cord not wider than 4mm
Watch this video for more info: https://youtu.be/CgwhFWUSm4o
It does have a tolerance of 0.2mm, so it should fit fine but snug.
I have included the f3d file (Fusion 360) so feel free to take a look (Good luck) and modify it if you want. For the other controller just mirror the mesh on your slicer(Now you can find it in the files too as Mamoth_v3_left).
Edit 25-5-2019: Added the hole for the strap at the bottom and reinforced the top part.
Edit 26-5-2019: Smoothed some sharp corners, replaced the top slot with two holes and thickened it.
Just try to have a solid infill at the thin part at the middle top
You shouldn't really need supports if you have good layer cooling, most printers would do well with an overhang lower than 60º