Intro: Cardboard Remote Controlled Car.
Wire controlled toys use to be the thing back before radio controlled ones became so common. Growing up I had several different types of wire controlled toys ranging from cars to planes, even a dude on a skateboard. My goal here was to make one out of the most basic of materials using as few parts as possible. Let's get started shall we.
Step 1: Tools & Materials Needed.
The picture above shows a few things you might need when building a wire controlled toy. Below is a list of all the things I used to build mine.
Safety glasses, scissors, knife, cutters, hot glue gun, soldering iron, screwdrivers, pliers, exacto knife, cardboard, 2 bottle caps, copper wire, telephone wire, craft sticks, wooden dowels, old ink pen, hole punch, elmers glue all, 2 toothpicks, 4 steel bolts, 4 washers, 4 nuts, electrical tape, rubber bands, 9V battery, 2 brass paper holder tabs, small spring (I got mine out of ink pen), circle compass, nail, nylon ties.
Step 2: Making the Remote & Wiring Up Left & Right Rear Motors.
I start out cutting out a piece of cardboard for my remote. I use 2 water bottle caps that rotate on toothpicks that run through their center. Rotating caps will be for left and right motor control forward and reverse. These caps each have 2 bolts running through with a 5 inch piece of wire attached using washer & nut on each bolt. These wires will be connected to the left and right motors. By rotating the caps the bolts make contact with a upper positive & lower negative will provide power to the motors independent of each other. The 2 bolts on each cap must strike both the positive & negative at the same time to provide power & rotating the cap the other way will reverse the polarity allowing the motor to go reverse direction. I got the basic idea for this remote from a youtube video by Indian LifeHacker : Science, Art & Magic so thanks to him for sharing that. The pictures can explain it better so look closely at them it's a very simple concept.
Step 3: Making Wheels, Pulley's, & Axles.
To make my wheels I used a compass to draw the right sized circle on a piece of cardboard. I then cut it out & used it to trace out 7 more & used the center hole from the original to find the center of each. I then cut out 4 slightly smaller circles for the rear wheels center which will be the pulley's which will be glued between the 2 larger pieces of each rear wheel. Each pulley is 2 cardboard thick & I place electrical tape around it to provide the rubber band a nice area to contact. I can now make my axles which I use old ink pen housing cut to proper length & run a wooden dowel through placing plastic retainers on each end & then slide the wheel over & hot glue it in place. Front wheels done the same way minus the pulley's. All 4 wheels are independent of each other & turn very easily.
Step 4: Remote 9V Battery Box.
Now I add the battery housing to the remote. The positive and negative terminals (which contact the bolts when turned) each have a wire soldered to them which will run to the battery leads. I use brass paper tab holders & a spring from the old ink pen to slide over them to keep tension on the battery terminals. The wires are soldered to the bent over tabs that run through a piece of card stock style cardboard doubled up. You can easily find where to run the tabs through the cardboard by pressing the 9V terminal firmly against the cardstock which leaves a imprint of terminals. Use exacto knife to make a small slit in center that the brass tab terminals can run through. Again the pictures can explain this simple concept much easier than words.
Step 5: Getting the Chassis Rolling.
I can now get the wheels added to the rear axles & figure out how far the motors need to be mounted away from them to make the proper pulley band tension. It has to be just right in order for the wheels to be turned by the motors. Once I get it right I hot glue the motors in place. I use telephone wire that has 4 strands of wire inside (some only has 2 so be aware of that because you need 4 for this application) to wire my remote to the chassis. I test everything a few times and when I get all the connections correct I secure all in place with nylon ties & hot glue.
Step 6: Making the Car Body & Adding It to Chassis.
With the chassis fully functional now I make my car body. I simply used cardboard & hot glue for this. This was a fun little project that can help you understand simple circuits & pulley's. It can be done in a matter of a few hours too so what are you waiting for? Let's see your creations.