I have to make sure each hole is positioned 7.5mm from the edge because I have to prevent the base holes from cracking near the edge.

To make the left and right plates and the back of the board fit more flush, I added protruding tabs to the left and right pieces and a matching groove to the back. In fact, I planned a single groove, but to ensure a tighter fit, I switched to a double groove.

 I also designed two 2mm insert holes to enable the front plate to open and close. These inserts align with the two round holes on the bottom plate, allowing the front plate to function like a door.

• The size of the upper & bottom plates are 62mm*85mm
• The size of the back plate is 70mm*120mm (70mm=85mm-7.5mm-7.5mm)
• The size of the left & right plates are 40mm*120mm (40mm=62mm-7.5mm-7.5mm-3.5mm-3.5mm), and 3.5mm is the width of two base holes.

The left and right protruding pieces are 3.5mm (width), and the groove in the base plate is also 3.5mm (height), ensuring a perfect fit for all three pieces.

The front plate is 70mm*120mm, and the two small raised sockets are 3.5mm, so the actual size should be 70mm*127mm. This ensures that the front plate fits perfectly in place as well.

This design drawing is an extension of the draft, using all components from Wooacry except for the two protruding inserts on the left and right plates, which are my own designs.