Electronic enclosure for Ender 3.x

ElEndBox is an electronics enclosure designed to fit the various components of a custom Ender 3 printer in a modular and evolutive way. All electronics are installed on a "blade" which can be reprinted and swapped if the component's layout need to change, without having to print a whole box again.

For this revision, it's currently designed to house :

• 1 SKR 1.3 logic board, or any board with similar dimensions
• 1 Raspberry Pi 3B+, or any board with similar dimensions
• 3 LM2596 DC buck converters
• 1 Trigger Relay Module High Power One Way High/Low Level Trigger Optocoupler Isolation Relay Module 30A YYG-2(5VDC)
• 2 WAGO 222-413
• 1 4020 fan

This enclosure is mounted on the back of the printer, instead of the front. As it is taller than the 4040 base profile, additional feet are mandatory to elevate the printer. Here's a suggestion. I also suggest to add a grill for the back of the fan too. Here's a suggestion too.

Key design features

• Spacious box to hold various electronics boards and allow leave some clearance for cables.
• Interchangeable bottom design makes it modular and evolutive, allowing future component changes without having to reprint a full box.
• Easy to open and service, just remove the 2 screws securing the top cover to access the electronics.
• Easy and vibrationless installation under the Ender 3, using M4 screws and T nuts to lock into the 4040 profiles.
• Sturdy and stable design, with accurate dimensions yet a bit of tolerance for easier printing and fewer after-print work.
• Power controlled printer using a trigger relay controlled with the Raspberry Pi.
• Cooled box using a 4020 fan controlled by the Raspberry Pi or the printer's logic board.
• Access to the Raspberry Pi ports.
• Dedicated holes for power, Y motor and stop sensor, bed, print-head and display cables.

BOM

• 22 M3x4mm screws to hold the various components and the bottom part in the box
• 5 M3x6mm screws to hold the top cover and one of the bottom corners
• 5 M2x4mm screws and 5 M2 nuts to bolt the bottom parts together
• 4 M3x25mm screws and 4 M3 nuts to hold the 4020 fan
• 6 M4x10mm screws and 6 M4 T nuts to secure the box under the printer
• Around 100m of PLA filament, or any other hard material filament if you prefer.

Installation instructions

1. Join the 2 bottom parts together using the 5 M2x4mm screws and M2 nuts.
2. Bolt the bottom part to the printer base using the M4x10 screws and M4 T nuts. 
3. Bolt all the components on the blades using the M3x4 screws.
4. Install the blades in the bottom part using the M3x4mm screws and the M3x6mm screw.
5. Lock the fan using the M3x25mm screws and M3 nuts.
6. Close the box using the top parts and the M3x6 nuts.