FranciK submitted a new resource: Simple 3D-printed V-slot insert to screw on accessories - Insert for the V-slot that accepts a 4 mm plastic/wood screw Read more about this resource...
I tweaked the dimensions so that it is snug (this is why ABS is recommended, it gives a bit). It was never a problem until now and I used 5 pieces so far. It could be a problem if you use a screw that is too big (>4 mm wood screw, I also used M3 screws for less critical parts), but you can still hold the insert in place using needle-nose pliers or a screwdriver.
FranciK updated Simple 3D-printed V-slot insert for screw-on accessories with a new update entry: Slight redesign to ensure better grip of the part inside the slot Read the rest of this update entry...