MMU2 Selector M1 with magnet

thingiverse

The sensor gets stuck because the sensor ball gets caught on filament remains, causing a false reading. You can see this when the red light on the sensor shows an incorrect reading. To fix this issue, add a magnet to pull the sensor ball down. This modification is inspired by a similar solution found online at https://www.thingiverse.com/thing:3264138. There are two versions of this mod: 1. M1_A uses a 10mm x 2mm flat coin-shaped magnet. 2. M1_B uses a 10mm x 3mm flat magnet with a hole from Hardhead, available at jula.com. M1_A has the strongest magnetic pull on the sensor ball, making it the preferred choice. However, M1_B also works well and was used extensively before switching to M1_A. Changes made to the mod include: * Chamfering the inlet of the selector from the MMU2 idler. * Adding a magnet chamber. * Replacing one of the 10mm screws holding the POM nut with a longer screw, 15-16mm in length. A tip from a Facebook group suggests raising the Finda prob as high as possible within its reading range to reduce jams and false readings caused by tips with tails. You can check your Finda reading range easily by observing when the red light is on or off. Set it to the highest position where the light remains off for optimal performance. As of 30.03.2019, the setup using M1_A has been stable and reliable. The total mods made to the MMU2 include: * M1_A selector (this mod) * MMU2 Idler body with gear (extruder) (another mod under my things) * MMU2 Pulley Body v2 Straight through feed (using push fit connectors for the tubes feeding the filament) * MMU2 Angled & Dropped Mounts (changing the angle of the mmu2 on the frame) * Running a standard extruder with modifications to avoid filament jams * Using auto rewind spools 3kg from vincent, which work well after some use. The spring is placed on the left side of the spoolholder for optimal performance.