All Aboard! VisualCAM Used to Replicate Historical British Locomotive
With the help of VisualCAM software, engineer Roger Froud of Amytech (UK) Ltd. is building his very own scale (1:11.3) working replica of the famous British Railway Systems Locomotive 1501.
The original locomotive now residing at the Severn Valley Railway, is a Hawksworth design 0-6-0PT tank engine built in 1949.

Roger’s working scale replica of the “1501” will be 900mm (35.4 inches) long by 254mm (10 inches) wide and 330mm (13 inches) tall. It will weigh 60kg (132lbs) and be able to tow 2 adults on a 5” gauge track!
This IS NOT a model kit! Roger uses VisualCAM software to machine the components needed in his working scale replica based on the actual 1940s designs. The images shown below show the Safety Valve and Top Feed components. The valve sits on the top of the boiler and also provides a route into the boiler for the feed water. The two flanges on the sides are where the water is fed in from the non-return valves that are bolted to it. There are two copper pipes inside the boiler that take this water to the front of the boiler and away from the hottest parts so that cold water doesn’t end up being ejected when the safety valves blow!

(Left) Completed safety valve body component. (Right) The safety valve body being Machined from Phosphor Bronze bar stock.

(Left) Final safety valve assembly. (Right) Location of the Safety Valve and Top Feed on the actual locomotive boiler.
“What’s interesting is that the physics of the 1501 Steam Engine does not scale, so you have to make very significant changes to the boiler design. There are approximately ten times as many tubes in a full sized boiler. Also, scale fittings and bolts become too small in some cases to be practical, so changes have to be made to hide the fact that some of the bolts are mockups. This is all part of the fun of doing it!”
Roger Froud, Amytech (UK) Ltd.
More About Severn Valley Railway
The Severn Valley Railway is a full-size standard-gauge railway line, running regular, mainly steam-hauled, passenger trains between Kidderminster in Worcestershire and Bridgnorth in Shropshire, a distance of approximately sixteen miles.
Additional Images
Here are some additional images of components of the 1501 Steam Engine replica created with the help of VisualCAM.

(Left) Working Steam and Vacuum brake valve. (Right) Valve crosshead in Aluminium Bronze.

(Left) Water gauge with working stop cocks and blowdown valve. (Right) Cylinders machined from 4″ Leaded Bronze bar.

LH Cylinder assembly.
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