Apprentice S15e cool cowl - replacement part

prusaprinters

On my second flight day my Apprentice S15e experienced a rapid unscheduled descent and consequently partial disassembly. The (let's name it...) crash wasn't very hard, but hard enough to brake the front wheel hinge and the cowl. A new original cowl would have cost me 7€ (+shipping) for around 25 gramms of plastic, so i thought: i can design it myself ! So i did, and here is my very own version of it ! It is heavily inspired by the original one (i didn't want to alter the look of this beautiful plane to much), but i gave it a little "belly" so the airflow should be inproved a little bit. I am not sure if it will make much of a difference, but i like the look of it. I printed my new cowl with a 0.6mm nozzle and 5% over extrusion, and got a total weight of 28 gramms. That is not bad compared to the 24 gramms of the orginial cowl (which is missing some bits, so maybe it was 25 or even 26 gramms before the crash). With a 0.4mm nozzle it would have been even lighter than the original one. But for me it's OK as it is, and will help to be a little bit nose-heavy (depending of the CG of your plane this is something you might consider too). Print Settings Printer Brand: Prusa Printer: Mk2.5sResolution: 0.2 Filament: unbranded PLA White Notes: IMPORTANT: Use 0 top Layers, 1 single perimeter and NO infill ! Print it nose down ! I have chosen 3 bottom layers. 2 might also work. I recommend to over extrude a little bit for better layer adhesion of the single perimeter. 5% should be fine. A smaller layer height might help with the steeper angles at the bottom of the print. I used the variable layer height feature of PrusaSlicer and increased the details just for the first 2 centimeters, and printed the rest at 0.2mm. Post-Printing You have to cut of the floating wall at the back of the "belly" where the front wheel goes into the fuselage. This is necessary because of the nature of the "trick" we use by printing only the perimeters without the top layers. But it's not a big deal and only wastes 1 or 2 gramms of filament. Category: R/C Vehicles