2020 Extrusion Slot Cover

thingiverse

This is a slot cover for 2020 aluminum extrusions (with dimensions like in the picture) to be printed with TPU. It uses little material and leaves the slot itself mostly empty so wires can be hidden inside. All model parameters are named and have descriptions, making it easy to fine-tune the model. The thick version will sit pretty firm and require some force to cut and insert. It uses about 15 grams of filament per meter. The thin version is supposed to be printed in vase mode. It is much easier to cut and insert, but is much softer and will not sit as firmly in place. It uses about 8 grams per meter. This was designed to print standing, multiple strips arranged in a circle (edit the Count parameter in the Fusion360 file if you want other numbers than 6 or 10). It was optimized for PrusaSlicer 2.2 to print in one go without any travel moves in between. ## Important Notes - For this to be sliced correctly, follow the settings below as close as possible. - Double check the slicer preview carefully to make sure that it looks like in the picture (especially that the little retainer nubs are present). - I strongly advise you to print pieces scaled to about 2cm Z-height first and test if they work out for you. - This is supposed to be printed very slowly to reduce vibrations and ringing as much as possible. The settings below will give you a speed of about 15mm/s. ## Dimensions Scale the model in the Z direction to fit your needs and print volume, but keep in mind that the nozzle will tug slightly at the print. The taller you go, the more mechanical advantage the nozzle gets. If you want to print more or less strips at once than in the provided STL files, edit the Count parameter in the Fusion360 file. I tested 6 and 10 and 11, with 10 staying pretty to the tallest Z. I believe the optimum to be between 7 and 10. In my tests, the following lengths printed beautifully (YMMV): - thin 6x: up to 170mm - thin 10x: up to 250mm - thick 6x: up to 220mm Going taller will lead to some waviness and not look pretty when installed. These numbers were obtained on a core-xy printer. If your bed moves horizontally, you may not be able to achieve those lengths. Dialing the feedrate lower on the printer halfway through (even as low as 50%) may or may not give you a few extra usable cm of Z-height, but my tests were inconclusive. ## Common settings for both versions Slicer: PrusaSlicer 2.2 Nozzle size: 0.4mm Layer height: 0.25mm Nozzle temp: 220°C Bed Temp: 55°C Fan: OFF Max volumetric speed: 1.8-2.0mm³/s Retraction: 1mm Lift Z: 0mm Skirt Minimum Loops: 1 Distance from object: 0mm Speed for travel moves: (larger than 30) First layer speed: 50% Acceleration: 900mm/s² ## For thick version Perimeters: 1 Extra perimeters if needed: checked Ensure vertical shell thickness: checked Avoid crossing perimeters: checked Detect thin walls: unchecked Detect bridging perimeters: unchecked Seam position: nearest External perimeters first: unchecked Infill: 0% Extrusion width: 0.425mm Slice gap closing radius: 0.049mm Elephant foot compensation: 0mm ## For thin version Spiral vase: checked Bottom layers: 0 Extra perimeters if needed: checked Ensure vertical shell thickness: checked Avoid crossing perimeters: unchecked Detect bridging perimeters: unchecked Seam position: nearest Extrusion width External perimeters: 0.41mm Extrusion width (all others): 0.42mm ## Post-printing 1. Find a pair of reasonably sharp scissors or similar. Important: DO NOT use your wife's/mother's fabric scissors under any circumstances! She WILL murder you, when she finds out. 1. Cut the pipe into strips 1. Cut the skirt off 1. Cut the correct length 1. Insert into the slot using appropriate amounts of force and patience