In setting out the hind wheels of a heavy waggon to run in line with the front ones, the height and dish of the wheels must be known. To enable these to be worked out, a sectional elevation is given of a 4-ft. 6-in. wheel with li-in. dish, the dotted lines A A being the tyre, and also showing the pitch out of the wheel, which is more or less according to the dish. To work to the wheels, put up a drawing of the hind wheel, mark in the bottom spoke B, and square up from the ground line. At C mark off the dish of the wheel; from the face of spoke at D intersect the mark at C, making the outer line A, which gives the correct position of the wheel. From the centre of the stock at the back E draw the vertical line F; from the same point draw the pitch line G, which is parallel to A. At H mark in the height of half of the front wheel, given in the sketch as 1ft. 9 1/2in. Measure the distance at H from the vertical line F to the pitch line G; this will show how much less the front wheel cuts under in its height than the back one.

Double this distance is the extra length required in the hind axle bed compared to the front one.

Setting Out Heavy Waggon Wheels.