| One end of the farm must be strengthened, and under the other put a skating rink - a needle. To better fit the bridge to the rink at unattached end of the farm set in a cargo guard booth. Under the rink must put mica and glass. Second side of the farm bridge roller can be left out. She needs only to give the model a more finished look. Rotate the arrows attached to the rink, will expand the bridge from the heat. The base model can be colored blue and green paint, depicting beach and river. 4. On board strengthens two racks and scale. Inclined copper plate or wire with one end fixed in the rack, the other end of the plate rests on the ledge arrow. The arrow is easily rotated around the axis between the rack and an arrow on the axis must wear two or three goals. Shoulder at the hands into which rests on the plate, is short and the plate is taken the least possible weight. Then, even mild heat plate will turn arrows on a certain angle. 5. To strengthen the stand two wooden racks. Inclined plane and its horizontal part are made from thin strips of iron. Strip width must be greater than the length of the rink, so you can make small bumpers along the length of the strip. Bumpers will guide roller for rolling along an inclined plane, but in no case should not hinder his movement. The distance between the bumpers should be everywhere a little longer than the ice rink. If you bring a lighted match to a steel wire (wire is necessary to take short), then heating it to lengthen and begin to move the short arm. The long arm describes a much longer path and pushes the metal roller. 6. On a wooden rack set in a light bulb 6.3 volts. Take two metal plates with a length of 70 mm and a cross-section, so they were not massive, but do not bend to its own weight. Plate is placed directly opposite each other. Between them should leave a small gap width of 0.1 mm or less (in the figure the gap between the plates, for clarity, depicts a large). Of heating on the spirit stove plate elongate, and the gap disappears. Circuit of an electric current is closed, and flashes a light. If you stop heating, then between the plates again with a gap, and the light goes out. |