Come along, as we reveal the mysteries of making sand-powered toys and puzzle joints in this venture into holiday toy-making. The sand motor toy is a copy of those manufactured around 1900. When you shovel sand in the top, it pours down and turns the wheel making the articulated figure on the side appear to turn the crank.
Make the box and tower from thin pine stock made by ripping 3/4 inch pine down its length.
Nail together the box and the tower, leaving a 3/8 inch hole in the bottom of the tower for the sand to run out.
Make the axle for the paddle wheel from a 3/8 inch dowel with a tiny nail and a bent paperclip for the crank in the ends.
The disc of the wheel is 2 1/4 inches in diameter with eight thin 1 x 1 1/2 inch paddles.
The articulated figure is most easily drawn first on paper and then glued to thin board.
Use thumbtacks through an oversized hole to make the pivot points at the hip and shoulder.
Next is a simple puzzle where three continuous pieces intersect without a break.
Because the joint is laid out in ninths of the thickness, the process will be easier if you start with stock that is 9/8 inch or 9/4 inch square.
Lay out the width of the intersections on all three pieces.
On piece A, cut down one ninth from the top, leave two ninths, and cut away the remaing six ninths.
On piece B, cut down three ninths, leave two ninths, and cut away the remaining four.
The height of the opening in piece C is seven ninths.
Cut away stock in pieces A & B to fit around the quarter section left in piece C.
Assemble by placing B onto C and then sliding A into place from the side.
Then slide the B & C up to cover the opening.
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