heel drive track welder into a two wheel drive. When the rail is greasy the one wheel drive slips. Since the track varies in width (especially on corn ers) the second wheel has to slide sideways using quite a strong spring.
It looks like this at the moment:
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It runs well about 95% of the time with one wheel drive. When the track is greasy the drive wheel slips. So if I run an axle across to the wheel on th e other side, that becomes a driving wheel too instead of a dragging wheel. There's not much force involved when the wheels turn at about 3 rpm. The simplest spline would be a tube and rod with a roll pin. If I can find some square tube I'll consider that.