Model of timbering an Australian Kalgoorlie main shaft

Model of timbering an Australian Kalgoorlie main shaft (scale 1:12)

This model represents the "box" method of shaft timbering used in Australian mines in the early twentieth century. In some mines the timbers were fitted closely together and formed a continuous box; in other cases the timbers were separated by "chocks" nailed between each timber set. A safer method was. as shown by the model, to form the raising chock of solid timber whereby the danger of a falling chock was obviated. This was known as the spaced method, and had advantages over the closed box, as it permitted of a certain amount of play in the timbers in expanding ground. There was also considerable saving in the quantity of timber required. The method was of course, inapplicable when the ground is bad, sandy, or of loose character.