2020 Extrusion Slot Cover

thingiverse

## Intro This is a slot cover for 2020 aluminium 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 so the model can be fine-tuned easily. The **thick version** will sit pretty firm and require some force 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 half way 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* ** Skirt height: *1 layer* Draft shield: unchecked **Minimal filament extrusion length: *20mm* ** Speed for print 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: *0.41* ** **Extrusion width (all others): *0.42* ** ## Post-printing 1. Find a pair of reasonably sharp scissors or similar. **Important:** DO NOT use your wive'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