Completed several engines with six ale out side frame trucks. These all have standard Athearn BB wheels which have been shown to not be good for train pulling. Yet these engines are all showing to be very good. The implication is that number of axles do have a significant contribution to the pulling capacity.
The results are still to be shown. The testing is bearing some interesting inferences. At this juncture it appears that the factors rank as follows:
- Number of axles, contact area increases by at least 50%.
- wheel material, elasticity of the wheel material seems to matter. Young’s modulus of SS is nearly twice that of NS. The impact on adhesion area is what seems critical.
- motor capability
- wheel diameter
- truck frame design, outside appears to be best
more tests to come, it will be fun to see how this comes out.
