I have spent an hour designing this piece for a client, this design work has been fully paid off. If you like feel free to share a penny :)

Glue-in Coin Slot Insert (Flush “Window” for Piggy Banks / Money Boxes)

This part is designed as a glueable insert that fits from the inside of a piggy bank (or any penny-bank style model) to create a clean, flush “window” opening.

When assembled, the front and back surfaces sit flush with the outer wall, so it looks tidy and finished from both sides. The insert guides the coin through while preventing it from falling back out.

This version is sized specifically to pass €2 coins — inner opening diameter is 26 mm.

Suggested use:

• Print the insert
• Glue it inside your bank model behind the window opening
• Align so both faces are level with the wall

Printing tips:

• PLA / PETG both work well
• 0.2 mm layer height recommended
• Increase wall/perimeter count for strength
• Light sanding can improve flush fit if needed

Feel free to remix for other coin sizes 👍