The design is dimensionally accurate, while simplifying the prototype's design some in the interest of easing production. The gibs in the axle box pedestals have been incorporated into the frame, and the rear extension is cut from the same thickness metal as the main frames. The pedestal binders are simple bar stock.
After much consultation with the readers of the live steamers and HO scratchbuilders discussion lists, I decided to equalize the running gear, but not spring it. This decision was based on the desire to maintain positive contact between the wheels and track at all times (which the equalization will do), and the difficulty of getting scaled-down springs to work properly. Many modelers have reported excellent results equalizing without springing, so I'm going to give it a try, too.
The photo included here was of the test cut of the frame, without rigging. The springs are 1:24 scale brass castings from Precision Scale, and will not be used on the final version. Cylinders are from Roundhouse Engineering; they will be covered with shrouds to bring them to accurate scale size.
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Updated on 1 May, 1998.