Y Axis Stepper Bracket for Geeetech I3

thingiverse

Update 2/4/2019 I added a 2-mounting-hole version that contains a near-minimum amount of unnecessary material. Don't forget to use the paper shim as shown in the photo. Let me know if anyone wants a version that uses sheet metal screws. When assembling a Geeetech I3 Pro B for a friend's grandson, I was concerned about damage during shipping due to the fragile appearance of the Y Axis Stepper bracket. However, I no longer have to worry about this, as the acrylic bracket shattered when the Y axis belt was tightened even modestly. The same bracket on my Pro C printer has seen much more tension for 3 years and is still okay. I looked at it and found that I had put a paper shim as above. Without that shim, the bracket undoubtedly would have broken with as much tension as sometimes gets applied to the Y axis. I wish my memory was better. Thanks to esurplusplus for designing a drop-in replacement for the broken bracket. I raised the position of the stepper 1.5 mm in order to give the belt more clearance from the frame when installing it with a half-turn, allowing the back of the belt to run over the smooth idler wheel. It requires about 4 meters of 1.75 PLA to print. IMPORTANT IF YOU PRINT ONE. CRITICAL IF YOU USE THE ACRYLIC VERSION. The stepper motor MAY be spaced out from the back plate by a mm or less. Adding a paper shim (cereal box paper thickness) to fill the space between the plate and the outer edge of the stepper will eliminate the bending stress on the bracket due to belt tension and keep the stepper motor axis perpendicular to the belt. See the shim in the photo. It can be the difference between breaking an acrylic bracket if you tighten the Y belt too much.