T-nuts for 5mm (and 6mm) 2020 Extrusion Slots

thingiverse

I own a Taz 4/5 and a Taz 6. I created a top-mounted spool holder for my Taz 6, only to discover that the slots in the 2020 extrusions were 5mm wide instead of the expected 6mm width on older models. I have metal T-nuts purchased from Amazon, but they are 6mm wide. Attempting to grind them down proved unsuccessful. I therefore designed some 5 mm wide T-nuts for M3 screws that worked adequately. I created these T-nuts out of PLA, PETg, and ABS. An M3 tap was used on most instances; however, you can successfully use a screw to cut the threads in place of it. Additionally, I have included designs for 6mm wide T-nuts using M3 and M4 screws. I strongly recommend utilizing a tap when creating M4 T-nuts to prevent splitting. Employing fine layer height is essential. I utilized .15mm with a .5 nozzle on the Taz and .4 nozzle on my new Prusa I3 MK3. It's always preferable to utilize metal T-nuts if available. Inserts in something this small do not function well. As long as you don't over-tighten the screws, the plastic ones will suffice. Include washers to ensure that the screws do not bottom out in the extrusion. I have yet to encounter any metal insert T-nuts for 5mm wide slots except for flat designs requiring end plates or corners to be removed. Someone using this design might create some metal versions!