1. Sumo Robot

2. Materials Part NameQty 3-9 volt Motor2 Gear sets2 Wheels4 Axles 4 Base1 Straws2 Switches2 Bolts & Nuts4 Hook up wire15'

3. Pictures

4. Drive Train

5. The Arena

6. The “Reversing” Switch Copper foil is glued to the piece of tinplate. Copper foil is glued and ready for cutting. The copper foil will be a better conductor for the switch.

7. Use tin snips to cut out the contact strip. Cut the strips into 45 mm lengths. You will need 4 strips to make your switch.

8. Divide each 45 mm contact in half by drawing a line at it's center. Use a pair of needle nose pliers to hold the finish nail. Using a hammer, drive the nail through the center of the contact strip.

9. Layout time. Draw a line across the switchboard, 10mm in from each side. Contact strips with nails ready to be place on the switchboard. Measure to the left and right 12 mm to get the second line for each switch. Cut a piece of thin plywood to 100mm x 60mm.

10. Locate the contact points. Measure 10 mm from the top and the bottom of each line and make a mark with your pencil. The centers are marked as close to the center as you can. Use the hammer and drive 4 finish nails through the switch board.

11. Time to nail on the metal switch contacts. The nails have been driven all the way through the switch board. Note: The nails are sitting on either side of the scrap wood. The scrap wood has been secured in the vice.

12. Solder a red and black wire in the diagonal pattern shown to the right. Solder a 300mm red and black wire as shown. These will be the contact wires for the power supply. Install the second switch and remove from scrap wood. Make sure the two metal contact switches DO NOT TOUCH. Place a piece of tape over the two strips.

13. SOLDERING The following is a summary of how to make the perfect solder joint. 1. Remove any rings for safety purposes. 2. All soldering component parts must be clean and free from dirt and grease. 3. Try to secure the work firmly (perhaps with tape) before starting to solder. 4. Clean the tip of the hot soldering iron on a damp sponge. 5. Add a tiny amount of fresh solder to the cleansed tip. 6. Heat all parts of the joint with the iron for a second or so. 7. Continue heating, and then apply a couple of millimeters of solder, to form an adequate joint. 8. Remove and return the iron safely to its stand. 9. It only takes two or three seconds, at most, to solder the average connection. 10. Do not move parts until the solder has cooled. First Aid If you are unlucky enough to receive burns which require treatment, here's what to do: 1. Immediately cool the affected area with cold running water for several minutes. 2. If you have not removed your rings as directed, remove them before swelling starts. 3. Apply a sterile dressing to protect against infection. 4. Do not apply lotions, ointments etc., nor prick any blisters which form later. 5. Seek professional medical advice where necessary.