PS Waverley Triple-Expansion Marine Steam Engine

PS Waverley is the last seagoing passenger-carrying paddle steamer in the world. Built in 1946 and now owned by the Paddle Steamer Preservation Society, she has been restored to her 1947 appearance and now operates passenger excursions around the British coast.

Since 2003 Waverley has been listed in the National Historic Fleet by National Historic Ships UK as “a vessel of pre-eminent national importance.”

Waverley is powered by a three-crank diagonal triple-expansion marine steam engine. The main crank is solidly attached to both paddle wheels so they cannot turn independently.

At the West London Meccano Society meeting in March 2023 I bought a full model of this ship’s engine from a well known member, who has always built very nice models.

I brought this model home and suddenly decided to try building my own model of this engine, since I don’t normally build this type of model myself.

I felt guilty having to dismantle his model, and with my respect for him and his work I decided to keep some fixtures built in his model.

I started dismantling all the moving cams, axles, top cylinders, main body built with yellow flexible plates, removed two motors and the gearing system to rotate the two paddle wheels, and the three flanged plates supporting the steam system to the boilers.

First I rebuilt all the supporting walls attached to the main base. I removed almost all of the bolts and hexagonal nuts, replacing them with new Allen bolts and nuts instead. I removed the tops of the four main front towers. I built all the rotating cams with new triangular plates in yellow and curved green strips, replacing the grey ones, fixed all new fittings and assembled all the axles and sliding system to the three main boilers. Three new cylinders also replaced the old ones with new fittings and additional fixtures.

I fixed a new motor and gearing system much nearer to the side wall so the driving units will operate much easier to power all the moving parts and paddle wheels.

All bolts and nuts in these wheels were also replaced and additional extensions to the eight blades of each wheel were also added with small flat girders. A black small unit built next to the three boilers was also replaced with a complete boiler instead.

The main moving axles were fitted with long red plastic tubes to enhance the overall look of the model. Two of the towers at each end were also increased in height.

The two sprocket gears used in the original model were part № 95, both of the same size, but I replaced them so the overall speed will be more controllable.

Finally the front of the engine’s four towers was also redesigned, removing all the long angle and channel girders.

I am fully satisfied with the final result and good functioning of the system.

I rebuilt this model keeping some fixtures built by the original modeller, such as the three main boilers, flat top base, and the black pipes at the back.