Page:Popular Science Monthly Volume 88.djvu/475

 Popular Science Monthly

��447

��box saw, and is continued part way up both ends as shown in Fig. 3.

Three 18 pieces of %" square iron or soft steel should be procured and the ends flattened, by hammering two opposite edges, for a distance of about IV2", and two 3/10 holes bored in each end so that the iron runners can be at- tached to the wood, after being bent while cold to the approximate shape, in the exact manner shown in Fig. 3. These iron runners are held in place by 3/10" brass screws countersunk. The screws should not be less than 1" long and should have flat heads.

If the wooden runners are over 1" thick they can be made of soft wood, and it will be possible to run the craft over the snow even if it is only packed to a small degree.

The small runner mentioned above is for the rudder, and is placed in the front of the machine. A %" round steel rod 17" long is sunk into the center of this runner to a depth of about 2", and is held in place by two 3/10" steel bolts which pass through the rod and runner, as in Figs. 1 and 5. Four or five %" washers are slipjjed on the rod.

Fig. 4 shows plainly how to lay out the sides of the boat body. Both sides can be cut from 7\{/ board %" thick by 12" wide. The dimensions are taken from the sketch and are laid out on the boards in the exact manner shown. The proper curve for the bow is obtained by marking ofl^ various points at different distances from the center lines, as shown, and connecting these points until a fair curve is obtained. Spruce is one of the best materials, as well as the cheapest, for making the body, but should be free from splits.

Nineteen i)ieces of V^" by 0" stock exactly 22" long are now required. These should be of selected sj^ruce and are used for the bottom and deck of the boat body. They arc laid on cross- wise. The side boards should be held the proper distance apart temporally by several short sticks nailed al \;irius points along their edges, and the entire bottom nailed in place with 2" nails. The bottom board should overlap about %" at the front of the body.

The rear c(]^c consists of a piece of spruce 20'/:i" long by 1" thick by

��2" wide. This is nailed in place between the sides before the first rear deck board has been laid on, and properly beveled at the same slant as the sides. The rear deck board is then nailed on, the nails along the back being set in %" from the edge. The rear edges are then rounded oft' to decrease the wind re- sistance, and give the body a finished ap- pearance. Two more 6" boards are then laid on, thus completing the rear deck, which is composed of three boards in all.

The deck board nearest the bow is now laid on in such a manner that its lower edge meets the front bottom board. First, however, it should be beveled to the proper angle to allow of a perfect fit. The top edge of the bot- tom board is then rounded over to a blunt point. These details are illustrated in Fig. 5. Three more top deck boards are then put into place. The front boards should be steamed before bend- ing.

In the third boards back from the front, on the top and bottom of the body, %" holes should be bored midway be- tween the side planks, and 2" in from the rear edge of the boards in question. The hole in the bottom board is re-en- forced by a Vs^ iron plate, 2" square, drilled in the center to correspond with the hole in the bottom plank. This plate is placed on the outside as shown in Fig. 5.

It is now in order to insert the up- right shaft, aflixed to the small runner, in the two half-inch holes bored for this ])uriM)se. The top of the shaft is then filed S(|uare in such a manner that it makes a good fit with the hole in the l)evel gear, of the rotating device of an old ice cream freezer, which turns the dasher. This mechanism is seen in place in ¥'\g. 5. It will be noticed that in this figure the housing for the gears is bolted direct to the u])per deck on the outside, while in I'ig. 1 it is placed under the deck. The former method of outside mounting is by far the simplest, and probably the best. The "crank shaft of the freezer mechanism is slipped into an 8" piece of heavy brass tube, which should fit snugly over it, and should be secured to prevent movement in any direction by two Is" pins passing through the tube and shaft. These pins

�� �