You are to plane a cylinder or axle which will fit the holes which you have bored in the paddle wheels. To plane this cylinder, first plane the stick perfectly square, then plane off the corners, making it an octagon. Again plane off the corners and continue planing off corners until it is as nearly round as possible. It can then be smoothed with a wood file and finished with the sandpaper (Chapter II., Paragraph 15). A round tenon is to be cut on each end of the axle (Chapter V., Paragraph 69).
As this material is furnished S 2 S, it will not be necessary to plane the surface. Select the best surface and mark it the working face (Chapter II., Paragraph 2). Prepare a working edge (Chapter II., Paragraph 4). Lay out the two side pieces and make them the dimensions shown in the drawing. You will note from the drawing that these two side pieces are to be fastened in position by a bottom and top rail.
Place the paddle wheel in position and see that it will turn very easily. You must remember that wood swells when it gets wet, and unless the turning joint is given considerable freedom it will not turn after the wood swells. Make it loose enough to allow a small brad to pass entirely around in the joint when the work is assembled. Carefully nail the frame together and test again to see that the wheel will turn very freely.
In as much as this piece of work is to be used in the water, it should have some sort of finish which will protect it. The easiest and best method of finishing it is to give it a good heavy coat of linseed oil and allow it to soak into the wood.
Optional and Home Projects Employing Similar Principles.
1. Make a water wheel as shown in this lesson, but let the axle extend about an inch beyond the frame on one side. Cut out a wooden pulley about 2 1/2" or 3" in diameter and fasten it firmly on the extended axle. Groove the edge of the pulley. Construct a framework to hold as many wheels or pulleys as you desire; connect them to your water wheel with strong cord used as a belt.
2. A simple water wheel which will furnish considerable amusement can be easily and quickly made of corn stalks. Select a corn stalk as nearly cylindrical as possible; cut a piece about 6" or 8" long for an axle. From another piece of stalk prepare eight or ten thin strips of the outside hard part about 3/4" wide and 3 1/2" or 4" long. These pieces are to be used for paddles. In the center of the axle piece cut slits equally distant all around; insert one end of each of the paddle pieces to form a complete wheel.
Cut two forked limbs and smooth the forks inside to form bearings for the axle. Drive the forks into the bed of the stream just far enough apart to receive the ends of the axle.