Fig. 208.—Plan of Motor Truck Bottom.
Fig. 209.—Section through Bottom.
Cut an opening through the cigar-box large enough for the two tumblers to set in. Then cut a strip of tin about 1 inch wide and 8 inches long, and bend it into a U-shaped hanger, to support the tumbler bottoms. Slip the hanger ends under strips A, bend them against the sides of the box, and fasten with tacks ([Figs. 208] and [209]).
[Figure 200] shows how the battery cells are connected. A small switch can be fastened to the side of the truck to shut off and turn on the current, but, instead, you can simply withdraw one pair of elements from its tumbler to shut off the current. When through playing with the truck, however, it is important to remove both pairs of elements and wash them off, because the bi-chromate solution attacks the zinc elements even when the current is not in use. As the bi-chromate solution stains very badly, it is advisable to operate the motor truck only where there is no danger of ruining anything in case some of the solution spills, as in the basement or workshop. If you wish to use a dry-cell instead of the pair of bi-chromate cells, you can place the cell upon the floor and make the wires connecting it to the motor long enough so the truck can run back and forth across a room.
Fig. 210.—Details of Seat and Canopy-top.
The Seat and Canopy-top details are shown in [Fig. 210]. Make these in about the proportion to the cigar-box shown in [Fig. 199]. Fasten the seat to the edge of the seat-back B with glue and brads, and then fasten the side pieces A to the ends of the seat. The dashboard E is nailed to the bottom piece D, and D is nailed to the lower ends of side pieces A. [Figure 211] shows the pattern for the canopy-top. Make it of light-weight cardboard, or heavy writing-paper. Slash the ends as shown; then turn down the corners, and lap and glue them to form the turned-down canopy ends. Fasten the ends to the canopy uprights with tacks.
