Preamble

This article documents my investigation into how LEGO trains interact with curved tracks. Specifically, the relationship between bogie distance, bogie size, and the bogies' pivot radius.

"LDU" below refers to LDraw Units, where 1 LDU ≈ 0.4mm.

We start with bogies with three bogie sizes:

Track sections

Just for reference. Only curved track is in scope for now. Curved tracks represent the tightest radius that a LEGO train would be expected to travel on.

Bogies on a curved track

At the same distance, they all seem to have the same rotation from their origin. In this experiment, different sized bogies are positioned with their pivot point 400 LDU apart, fit onto the track while rotated 14.2° from their origin.

Different size trailers

At different distances, they have different rotations from their origin. In this experiment, identical 60 LDU bogies are positioned with their pivot points at different distances, which affects the rotation from their origin.

With these datapoints, we can approximate the relationship as , where is the pivot point distance in LDUs, and is the bogie rotation. We can use this to evaluate different LEGO: Train bases.

This article is part of the LEGO set. Feedback? Questions? Let's discuss on Mastodon, or email me

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