Modelled after the first known depiction of a railway cart, 1556 in De Re Metallica
Also called mine dog due to the whining sound the cart made when pushed along the wooden tracks.
https://en.wikipedia.org/wiki/De_re_metallicahttps://en.wikipedia.org/wiki/De_re_metallica#/media/File:Leitnagel_Hund_(Mining_cart).png
Designed for filament print.