Filament Guide Pulley for Ender 3 with Dual-Drive Extruder Upgrade

This is a remix of tim17's 608 bearing filament pulley. I liked the way the original eliminates filament abrasion rather than just relocating it as some other filament guides do. I've adjusted the design to work with the dual-drive extruder upgrade I have on my Ender 3. The dual drive extruder has a higher filament feed hole than the stock extruder. I've raised the pulley mount enough to compensate so that the filament still feeds in at 90 degrees eliminating any dust caused by abrasion on entry. PS. I found I needed a couple of longer M3 screws to mount. The stock 10mm screws only just reach, so if you like to be able to adjust those lead screw guide screws to tweak z-axis performance go for something 12-18mm long to leave you more capacity for adjustment. A couple of spare 18mm M3s I had on hand worked well, allowing plenty of room to back off the two lead screw guide screws a little after installation to prevent any z-axis binding/slipping.