M3 T-Slot Insert for 2020 extrusions w. 5 mm slots

thingiverse

In the midst of building my custom Mini Kossel delta printer, I discovered that I was rapidly running out of t-slot inserts. Frustratingly, purchasing replacements either entailed paying a hefty premium for shipping or buying them from China and waiting two excruciating weeks. I had to come up with a creative solution. Luckily, I had an abundance of common nuts and washers at my disposal, so I took matters into my own hands and fashioned my own inserts instead. They worked like a dream! The M3 nut combined with the M4 washer (diameter 8.9mm) fits snugly inside and handles all the axial stress effortlessly. The printed components make it simple to install the insert and prevent the nut from turning prematurely. I utilized 2020 extrusions with 5 mm slots courtesy of Motedis, but I'm confident these will fit similar profiles as well. Please keep in mind that you must print the inserts with either the nut+washer side facing upwards or standing upright. Unfortunately, my .stl model isn't properly oriented at the moment; I'll make the necessary adjustments shortly. Here's a concise guide: As the parts are quite compact, it's advisable to use a well-calibrated printer. I recommend printing them using fairly fine settings – 30 mm/s and 0.15 mm layers was a decent balance between quality and speed on my trusty Printrbot Simple Metal (approximately four minutes per insert). To assemble your custom inserts: 1. Print the parts without supports, ensuring they're facing upwards or standing upright. 2. Gently insert an M3 hex nut into place, utilizing pliers if needed for extra leverage. 3. Follow up by inserting the M4 washer into position; again, pliers can come in handy here. 4. With your inserts securely assembled, you're ready to build!