By the time I took this video, I had gotten most of the bugs (and initial operating stiffness) out of my new Accucraft Mason Bogie 2-6-6T. Never really a popular choice for prototype railroads. The articulated design caused the driver flanges to wear exceptionally fast due to "wandering" and the steam swivel took up a lot of space forcing them to design the reversing linkage on top of and outside of the boiler. When William Mason died, so did the design. But this model of a late 1870's Mason Bogie is representative of what the design was all about.