Customizable LEGO-Compatible Brick with car wheel axle groove

Give a second life to wheel sets from broken toy cars — turn them into custom LEGO-compatible car instead of throwing them away!

This customizable brick features a groove on top for holding an axle, with adjustable groove diameter and optional side filling for better stability.
It also comes in a 2/3 block height version, which allows you to add a reinforcing plate underneath when needed.

2025/10/07: Changed some default values and the range of values ​​for the groove diameter and lateral expansion has been expanded.
2025/11/22: Added negative values ​​to the additionnal filling parameter in case a standard-sized Lego brick doesn't fit into your wheelset quite yet.
2026/02/14: Added LEGO DUPLO brick support.

This model is based on cfinke's Customizable LEGO-Compatible Brick.