Einhell GE-CT 36/30 Li Trimmer Spool

prusaprinters

This is a spool (for the nylon strand) for the Einhell trimmer GE-CT 36/30 Li from the Power-X-Change family. It should also fit for to Agillo trimmer. My spool gave up after ~1 year by being chafed through. I think a new one is way too expensive (~15€) and buying one each year produces too much waste for something that shouldn't fail so soon.There are two versions of the spool: 1) the original one and 2) a durability optimized spool, meant for FDM printers.I guess the spool is best printed in Nylon. I've used regular PLA (maybe use PETG to improve thermal conditions) and used a trick to make it way more durable - keep reading!In general, this part expects a well calibrated printer!I recommend printing the FDM-optimized version using a few slicer tweaks and 0.2 mm layer height. These tweaks expect that your printer allows basic bridging performance for 25 mm. If this isn't true for your printer, use regular supports without these tweaks!use supports to get the bottom part rightadd a support blocker for the hole to the top, in the middle of the spool (see design description)use bridging settingsmodify the infill and wall settings of the top 2-3 mm to make it more durable: infill: 50%, walls: 5 or infill: 100%The basic idea of the optimized version is that a metal washer gets into contact with soil and stones, not the plastic tip. This way there should be little to no abrasion of plastic, but you might need to exchange the metal washer from time to time. Read the post-processing section for assembly.Enjoy a spool that won't wear for several years!Notes:Best printed with Nylon. Second-best chance is ABS or PETG. PLA might be also okay, but I haven't tested my PLA printed version yet. I'm not sure if it will resist a heated washer.Post-Printing:Break supports apartCheck whether the nylon string fits into the two little holes - if not, use a 2mm drill to open these upuse a 6mm drill to remove the bridging layer in the hole at the tipFor the optimized part:Place a large washer (>=31mm) at the tip (outside) and a smaller washer (<=25mm) inside the tip. Use a M6 screw and nut to secure the two washers. Maybe add a circlip to the nut. Don't over-tighten the screw - it's just plastic!Designed margins are small. If your print won't fit to the machine you may need to post-process it, e.g. by sanding it.How I Designed This:The replacement part is designed precisely after the original spool.There are general tweaks for better FDM printability:The inner hole was widened by ~0.1mm to 25.1mmThe outer tip diameter is shrinked by ~0.05mm to 30.95mmThe design of the optimized version was changed in the following points:Added a cone where the nylon filament will be - about 55° for easier printing without supports ... reduces how much nylon filament it takesAdded a 6mm hole to the top for a M6 screwAdded a 0.2mm bridging layer to top, so you don't need support within the inner hole