Magnetic MTV Kit User Guide Components The Magnetic MTV Kit should contain the following items. If anything is missing, call Customer Service at 800-358-4983. Two 3" x 18" sheets of 1/4" balsa wood Mousetrap 4 CD wheels 4 CD hubs (on font) 12 screws 4 neodymium magnets 4 bushings (on font)* 2 axles String String anchor (on font) 12" hollow tube * The bushings are not used on the Magnetic MTV Kit but can be used on a traditional mousetrap vehicle. Study this picture of the Magnetic MTV to familiarize yourself with the names and arrangements of the parts. Front wheels Lever arm (hollow tube) Side rail support CD hub with screws Brace Side rails CD hub with screws Deck Side rail support String Rear (drive) wheels Keeper Figure 1 Magnetic Mousetrap Vehicle parts 58180 V0410
Items Required (not included) Hobby knife Ruler and yardstick Small Phillips screwdriver Drill press and 1/4" drill bit Wood glue or Pitsco Insta-Cure (wood glue will take longer to dry) Long-nose pliers Masking tape (optional) Pencil Wire cutters 1/4" diameter rods (optional) Paint and decals to decorate the MTV Constructing the Magnetic Mousetrap Vehicle Make the Parts for the Chassis 1. Cut two strips 16" long and 1/2" wide from one of the balsa sheets. Cut each end at a 45-degree angle (Figure 2). Be sure to keep one side of each strip 16" long. These are the side rails. 2. From the same balsa wood sheet, cut two strips 15" long and 1/2" wide. Cut each end at a 45-degree angle (Figure 2). Be sure to keep one side of each strip 15" long. These are the side rail supports. 3. Measure the width of an axle. From the second balsa wood sheet, cut a rectangle 5" long and 1/16" wider than the axle is long (Figure 2). This is the deck. 4. Cut another piece of balsa wood 1/2" wide and 1/16" longer than the axle length (Figure 2). This is the brace. 5. Cut two tiny rectangles from the balsa wood, each measuring 1/4" x 1/4" x 1/2". Carve an arch in the center of the long side of each (Figure 2). These are the keepers the parts that will keep the rear (drive) wheels in place while the MTV is in motion. Brace width of Deck x 1/2" x 1/4" Deck 5" x length of axle plus 1/16" Keeper 1/4" x 1/4" x 1/2" Side rail supports 15" x 1/2" Side rails 16" x 1/2" Figure 2 MTV chassis parts 2
6. Hold the side rails firmly and exactly together. (You may wish to tape them together with masking tape.) Drill a 1/4" diameter hole through the rails 1" from the pointed ends (Figure 3). Later, the magnets that hold the axles will be placed in these holes. It is important that the holes be drilled in exactly the same place in each rail. If the holes are not even on both sides, the axle will attach at an angle and your vehicle will not travel in a straight line. 7. With a pencil, mark a line around the rails 3-1/2" from one of the pointed ends (Figure 3). This is the alignment mark for the deck. 8. Remove the masking tape. 1" 1" Mark 3-1/2" from end Figure 3 Drill holes through both side rails in exactly the same place 3-1/2" Assemble the Chassis Be careful while gluing the deck to the side rails. You must keep the holes positioned exactly opposite one another. The reason is that the axles are suspended between the magnets in the holes. If the magnets are out of alignment, your axles will not be straight. Your vehicle will travel at an angle and the wheels may wobble or even fall off. 1. Glue the deck lengthwise between the side rails (Figure 4). The top edge of the deck should align exactly with the pencil marks on the side rails. Before the glue dries, check the axle alignment by slipping a 1/4" rod through the holes. If the holes are not exactly aligned, make adjustments before the glue dries. 2. Glue the brace between the side rails 3-3/4" from the opposite end (Figure 4). Side rail 3-1/2" Deck Side rail Brace 3-3/4" Figure 4 3
3. Glue the side rail supports perpendicular to and centered on the side rails (Figure 5). 4. Slip a magnet partway into each of the drilled holes. Smear a bit of glue around the magnet and slide it all the way into the hole (Figure 5). 5. Center and glue a keeper lengthwise over each drive wheel magnet (Figure 6). The top of the keeper should be flush with the top of the side rail. Note: The drive wheels are those in the rear of the vehicle, closest to the brace. Side rail supports Keepers Figure 5 Figure 6 (above and close ups below) Keeper Keeper 4
Bow Spring arm Bait pedal 6. Locate the mousetrap and note its parts (Figure 7a). With long-nose pliers, remove the locking bar and bait pedal (Figure 7b). With wire cutters, snip off the right side of the bow (Figure 7c). Using long-nose pliers, straighten the bow (Figure 7d). Locate the hollow tube. Slide it onto the straightened bow (Figure 7e) to make the lever arm. Make sure that the spring arm of the mousetrap rests on top of the lever arm (tube) as shown in Figure 7e. Locking bar Figure 7a Mousetrap parts Figure 7b Remove the bait pedal and the locking bar Figure 7c Remove the right side of the bow Figure 7d Straighten the bow Figure 7e Slide the lever arm tube onto the bow and under the spring arm 5
7. With the lever arm extending toward the front of the vehicle, glue the mousetrap to the upper right-hand corner of the deck and right side rail (Figure 8). 8. Locate the string. Tie one end of the string to the hook at the end of the lever arm (Figure 9). Tie a loop in the other end of the string. Figure 9 Figure 10 Figure 8 Assemble the Wheels and Axles 1. Locate the axles and screws. Remove the hubs and string anchor from the font. 2. Slide the string anchor onto one of the axles and center it (Figure 10 above). 3. Slide a hub onto each end of the axles (Figure 11). The tips of the axles should protrude 1/4". 4. Center a CD on each hub (Figure 12), insert screws, and tighten them with the Phillips screwdriver. 5. Slip the wheel/ axle assemblies between the magnets. (The axle with the string anchor goes on the rear of the MTV, underneath the keepers.) The magnets will grab and hold the axles. Your MTV should look like the one pictured on page 1. Figure 12 1/4" 1/4" Figure 11 1/4" 1/4" 6
Get Ready to Roll! Take your MTV to the area you have selected for racing. A long uncarpeted hallway is ideal. Slip the loop at the end of the string over the string anchor on the rear axle. While a friend pushes back and holds the lever arm, carefully rotate the rear wheels counterclockwise to wind the string around the rear axle. Note: The direction of winding should be opposite of the direction you want your vehicle to go. When winding is complete, continue to hold down the lever arm, place your car on the floor, and then let go of the lever arm. The vehicle will speed forward propelled by the power of the mousetrap s spring! Designing Your Own Magnetic Mousetrap Vehicle You have successfully constructed one kind of magnetic mousetrap vehicle. Now, try to build one of your own design. Here are some tips for creating your unique vehicle. Brainstorm a design for a Magnetic MTV. The design will differ from that of other mousetrap vehicles because the axles must be mounted between the vehicle rails, not through them. Then, make a detailed sketch of your design that shows dimensions. A successful design will include these features: A vehicle body that is 1/16" wider than the axles. Side rail supports or braces. These keep the magnets embedded in the side rails from pulling the rails together. Magnets that are positioned exactly opposite one another. This guarantees that your vehicle will travel in a straight line. A device that prevents the drive-wheel axles from pulling out of the magnetic field. This can take the form of keepers mounted inside and above the axles or an angle-cut plastic straw that houses the magnet and surrounds the end of the axles (Figures 12 and 13). Figure 12 Figure 13 7
Other Ideas for Mousetrap Fun: Build a mousetrap boat. Build a mousetrap catapult. Will this design work? Why or why not? P.O. Box 1708 Pittsburg, KS 66762 www.pitsco.com Toll-Free Orders 800-835-0686 8