At first glance, this steam roller appears to be a one-off home made item. However, several examples have been seen, and also a similar traction engine. The chassis and bodywork is made from galvanised steel and painted. The boiler and engine parts are brass.
The boiler is 1 1/4" diameter x approx 3 1/2" long. It's heated by a single wick meths burner, which is built into the chassis. The meths tank is the bottom section of the bunker. The rest of the bunker serves as a filling funnel. The boiler is filled through a plug in the side of the boiler. There is no water level indication.
Steam is fed through a very short pipe to the bottom of the port face of the oscillating cylinder. The cylinder is a single acting oscillating cylinder, 9mm bore x 20mm stroke. The port face is lubricated by a wick type oiler. The piston has to be oiled manually. The piston is connected to a simple crank on one end of the crankshaft. The other end has a 2" diameter brass flywheel and a small gear. This forms the first part of a three stage gearing transmission to one of the rear rolls. The total gear ratio is about 100:1. There is a simple clutch, formed by a sliding gear and operated by a lever and linkage. The front rolls are steered by means of a traditional worm gear and chain arrangement.
The engine was acquired in a very poor condition. The front king pin mounting had come unsoldered, which was not surprising as this was a week point in the design. I repaired it, strengthened with a brass block. The thread on the filler plug was stripped and the plug had to be forced off. I have drilled and re-tapped the filler hole and the old plug has been modified to fit by a good friend.
Some of the joints in the bodywork were also in need of re-soldering. There was a serious leak in the meths tank, which I had to cover with a brass plate. The paintwork was generally in poor condition anyway so I have repainted it.