N scale truck rolling resistance tester

thingiverse

A simple 900mm Radius arc is ideal for mounting flex track to test how freely rolling your trucks are. In N-scale, an entire car can be placed on the track and tested as a whole. This design fits perfectly on a 200x200 print bed. To begin testing, place the truck at the top mark, release it, and count the number of direction changes. A bad truck will typically change directions 3-4 times, while a good one will change directions 6+ times. Next, place a whole car with its center aligned with the 2nd mark. A free rolling car will change directions 4+ times. I have noticed that some cars only change direction once, and it's essential to test each car thoroughly. Interestingly, adding an additional car weight to an already weighted car does not significantly affect the outcome. To ensure consistent results, I'll be standardizing on 4+ direction changes as a benchmark for a car to run on the layout. The pennycar is a perfect tool for testing trucks without mounting them to a car body. It requires just 10 pennies and weighs over 1oz, making it an ideal stand-in for a 50' car in NMRA tests.