Comprehensive guide to brick sizes

[Chris Dee]

An interesting dissertation, but Agh!!! - the old 0.4 mm vs. 1/64 inch discussion, yet again.

However, the remark on real world approximations given on that page is wrong: at room temperature 1LDU is certainly exactly 0.4mm, and the value 1/64 inch is certainly wrong. The LDraw brick models will nevertheless work fine between themselves. They are approximations of the real bricks, as I argue below, and in the C4D models I make for myself I also use some approximations.

The original (British) design by H H Fisher Page for Kiddicraft used imperial measurements.