Fig. 4
Fig. 5
Fig. 6
Now the bearings for the crank-shaft must be made. [Fig. 4] is a perspective view of one of these. Get two pieces of brass one inch long, half an inch wide, and a quarter of an inch thick, as [Fig. 5]. Along the face of each block draw a line, dividing it lengthwise into two equal parts, and in the centre of these lines drill a hole right through the brass one-eighth of an inch in diameter. Cut the brass away at the ends (as in [Figs. 4] and [5]), leaving the projecting pieces a quarter of an inch long and a little more than one-sixteenth of an inch thick. Through each of these flanges drill a hole, to screw the bearings to the bed-plate by. Drill two holes down through the top of the block, passing one on each side of the bearing-hole (as in [Fig. 5], the dotted lines showing the positions of the holes). Drill a small hole through the top of the cap into the bearing-hole, for oiling purposes. Cut the block in two along the line passing through the middle of the bearing-hole with a stiff-backed saw. This will make the block as in [Fig. 6], having a movable cap which can be fastened in its place with two screws. Screw these bearing-blocks in their places, one at each end of the bed-plate, using the same care to get them properly centred along the line C D and at right angles to it.
Fig. 7
