Hopet Automatic Chicken Coop Door Gear Replacment

I received a Hopet Automatic Chicken Coop Door for $1 because the gear was skipping when trying to open the door. The clutch mechanism is poorly designed with the grooves and lands too shallow to give the necessary torque if not manufactured to tolerance. 

This replacement gear presses onto the metal piece that slides onto the shaft, using friction to hold the gear.  The downside is you lose the clutch mechanism which is a safety to not crush chickens or burn up the motor.

Print Specifications:

• Walls: 999
• Infill: 100%
• Orientation: Large hole facing up
• Supports: yes. 
  • The bottom will have supports under it. Supports are easier to remove this way and won't cause shaft fitment issues.
• Material: eSun PLA+
  • PLA+ was used for its deformation properties over standard PLA. PETG may work just as well as it won't warp over time though it may crack when pressed in.

Install:

• Unscrew the housing.
• Remove the screw from the shaft.
• Remove entire gear and clutch.
• Remove the clip to release the gear and clutch. A special tool will make it easy. 
• 
• Get the cylindrical piece that was on the shaft and press it into the gear.
• 
• Place the married pieces onto the shaft and screw it in place.
• 
• Reassemble the housing.

Created with FreeCAD's gear addon.

https://github.com/looooo/freecad.gears/blob/develop/README.md