2020 T-Slot Extrusion Joining Plates

thingiverse

This is a set of joining plates for 2020 aluminum extrusions. You can buy them anywhere in aluminum, but printing them is much cheaper, making it possible to use more of them for added strength. They're a drop-in replacement for any comparable aluminum plate (keep in mind that they are still plastic parts, and even at 100% infill, they won't be as strong as an aluminum part - but for most low-heat, low-torque applications, they should be fine). I've modified the standard design of these plates for 3D printing. Their sides are filleted to prevent ringing when removed from the printer, even with a direct drive printer. I've also added slight fillets to the top and bottom so that if your initial layer height is slightly low, you won't get bulging on the edges. This also makes the plates easier to remove from the build plate. Before printing the ones you need, try printing a single 2-hole plate to ensure your print settings are correct. These plates are compatible with both button head and countersunk M5 screws. I used 8mm screws without any issues, but I think 10mm might be preferable. You'll also need some M5 T-nuts. The countersunk screws sat flush with the plates in my tests; try adjusting your slicer settings if they bulge out for you. If using button head screws, attach them from the bottom (flat) side. Despite the chamfer on the opposite side, they should work fine. If your application applies too much pressure for them, you might want to be using metal joining plates anyway. I've left the Fusion360 file if you'd like to modify them. If you find a problem with them, please let me know so I can update the Thing and give you credit.