Content copyright © Tramway Museum Society of Victoria Inc. Reproduced with permission.
One of the smaller classes of Melbourne tram was the W3. With only sixteen examples being constructed, four complete vehicles still exist retained by tramway museums. With the return to traffic of the TMSV’s W3 667 shortly, it would be interesting to return to their beginnings nearly 70 years ago by reading the following contemporary article.
The last tramcars built by the Melbourne & Metropolitan Tramway board have been designed with the special objects of improving the riding qualities and reducing noise. These expected improvements have been more than realised. These cars, which are known as the W3 class, have been built on the same general outline as the standard car known as the W2 class. They have been designed and built under the supervision of the Board’s Chief Engineer Mr T P Strickland by the staff at the tramway workshops at Preston.
Each of the new cars are 47 ft long, 7ft 6in wide over pillars and 9ft wide over footboards. They are 10ft 5in high from rail to roof and weigh 15tons 14cwt. The seating capacity is 52 persons but the total crush loading capacity is 150 passengers. There are three entrances on each side to the smoking compartment, which has cross-
The roof is of 5/16 in plywood covered with Caledonian roofing, the roof sticks are of Australian Blackwood and the interior finish of the plywood roofing is Australian walnut. Tongue and grooved Baltic pin ¾ in thick forms the flooring in the saloons and wood slats in the smoking compartment. Aluminium angle finishing pieces are fitted to all doorways and along the footboards, both reduce wear and to show up the edges at night. Polished plate glass 3/16 in. thick is used for the end windscreens, while the remainder of the car 26oz mechanically-
The bulkhead framing and doors are made of Tasmanian mountain ash, panelled with Queensland maple. The cross bench seats in the smoking vestibule, and the saloon seats are built of Tasmanian mountain ash and blackwood framing around three-
An entirely new design of bogie truck has been developed in connection with this car. This truck is new to tramcar design in that the springing has been made similar to motor car practice, ie long semi-
The materials used in the construction have been selected to give minimum of weight fro the strength required. All castings where strength and wearing are required have been made of steel, and others such as axle box lids of aluminium. All springs have been made of spring alloy steel. Electric welding has been availed of where possible in the construction of the trucks. The bolster is built up in box sections with top and bottom plates ½ in. thick and web plates ¼ in. thick and electrically welded with no 10/8 run along all four edges.
The side frames for the first of these trucks were made of cast steel, but these proved to be rather heavy and the mild steel side frames were developed. These are made by using a pieces of 7 in. x 3 ½ in. x 15 lb I-
The braking on these trucks is also a departure from the conventional design of fitting one brake cylinder on the car body and operating through foundation brake rigging to the brake gear on the trucks. On the new design, the brake cylinders have been fitted upon the trucks and operated directly upon the brake beams. Clasp brakes have been fitted to the wheels and although this is standard practice in railway rolling stock, it is new to tramcar design. The advantages found with the clasp brake compared to single shoe brake are smoother retardation, less tendency to skid the wheels and only half the consumption of the brake shoes per annum for the same class of car. The air cylinders are connected to the straight air brake system through a relay valve by a flexible hose. The hand brakes operate for one truck only and are not interconnected throughout the car. The use of the two brake cylinders on each truck eliminates heavy brake cylinder on the car body and all brake levers, rods, pins, etc., with their loss of efficiency weight and noise.
The car is equipped with four 40 hp Metropolitan-
Complied and reprinted from “The Electrical Engineer and Merchandiser” for March 1932 by Graham Jordan.