Sawmill Industrial Locomotives

A New Zealand Forestry Service industrial rail system at Waipa near Roturua NZ using a 3ft 6in rail track to load wood into a steel pressure cylindrical vessel used in a vacuum/pressure wood treatment system.

Details of the diesel powered rail tractors used by the sawmill at Waipa [NZ] are as follows;

Builders #10224 of 1955, 3ft 6ins gauge, 4wDM 32/42hp ordered by Railway Mine & Plantation Co Ltd, London. It was used by the New Zealand Forestry Service sawmill at Waipa, Roturua and later went to New Zealand Co-operative Dairy, Waharoa, c.1966?

Builders #10457 of 1955, 3ft 6ins gauge, 4wDM 32/42hp ordered by Railway Mine & Plantation Co Ltd, London. It also was used by the New Zealand Forestry Service sawmill at Waipa, Roturua New Zealand. It later went to the Co-operative Dairy, Waharoa, c.1966 Preserved on site 1982.

A locomotive described as 4wDM is a four wheel locomotive fitted with a diesel engine and a mechanical transmission.

Sawmill Industrial Locomotives

Sawmill owners invested in wood treatment plants to enable them to produce timber products resistant to insect attack. If timber is made more resistant to insect attack the life of the timber is greatly extended and thus reducing the amount of timber that needed to be harvested.

Sawmills with a large output sometimes had a rail system complete with a small rail mounted locomotive or rail tractor while smaller operators just used their forklift or rubber tyred tractor crane to shunt the wagons into and out of the wood treatment cylinder.

The size of the rail system again depended on the size of the operation. If the sawmill processed long timbers such as electricity poles or wharf piles, than the rail wagons and rail tracks used to load the timber into the pressure cylinder would be more extensive than that used by operators who processed shorter and smaller wood products.

In a similar manner, the pressure cylinder size depended on the operators’ needs, as did the rail track size and gauge.

General view of a steel pressure cylindrical vessel used in a vacuum/pressure wood treatment system

I am thankful for the Waipa sawmill locomotive history data kindly provided by David Hall of England and John Browning of Queensland.