I have been working away on various bits of the design for the Class 70, mainly on the Bogie design.

I have decided to custom make the wheel sets for this as I like the idea of plenty of power combined with a fully enclosed gearbox. That means a modified motor and complete fabrication of the gearbox assembly.

This is what I have to date. The funny breaks are where the various sections on the bogie frame will be welded together. I intend to use a fair bit of lost wax casting on this project, hence casting in the weld prep where I want it.

Interestingly from my calculations so far, although this is drawn as a 3 motor set up, the 3rd motor adds no real benefit. If 2 motors can produce more power than can be put down onto the track then adding a 3rd actually reduces the tractive effort available to pull away. I have drawn it as a 3 motor setup mainly to confirm that if needed, a 3rd motor can be added. As it stands, the centre axle will probably be free wheeling and very lightly sprung so that the weight falls on the power producing axles at the end of the bogie.