I had two Root and Vandervoort hit and miss engines (one vertical and one horizontal) which needed carts to finish them off. This is how they were made.

Starting off with the horizontal I was given a couple of photos of the desired type of cart, possibly a bit large for this engine which mostly just came on skids or, occasionally, a two wheeled barrow type cart.  So something was drawn up to suit wheels that could be made from available tube sizes and allow a decent amount of steering lock before the front wheels hit the rails. I also had to incorporate the fuel tank which is housed in the wooden frame.

This pic shows the rear axle brackets on the full size cart.

Not being the type to waste time fondling castings a couple of bits of bar that had been cut out of a crankshaft and a piece of angle iron were cut roughly to length.

The bar was milled down to a rectangular section then held in the 4-jaw to drill through 3/8" and turn a taper along part of its length. The angle had one leg reduced to 3/4" internal and a recess milled to locate the bar. Also a small web was cut and filed up from some 1/8" offcuts and shallow locating grooves milled for that, too.

After silver soldering the bits together they were cleaned up and the corners eased to make them look like cast items.

This is the front bolster that needed to be copied.

It was made mostly from 1/8" flat bar with locating grooves as before which kept everything square while it was soldered. The pivot fork was turned and milled from some 2" bar, there is a matching 2" disc under the bolster for this to bear against.

I did not take many photos of the axle being made but it is basically a 9/16" rod reduced to 3/8" at each end for the wheels, a short section then reduced to 1/2" which the lobe shaped brackets fit to and a milled and turned central block that was slid along the axle before it was all soldered together. The pivot hole was then drilled through both parts.

The handle was bent up from 2ft of 3/16" steel bar.

The front end assembled.

part one here  part two  part three part four part five part six