Toy Fire Trucks and Diesel Engines I have always been fascinated by mechanical equipment ever since I can remember. When I was a child in Jamaica, I remember that we had very few choices of toys to play with compared to children today, especially in the United States. I learned very quickly that it was always going to be up to me to keep my toys working properly and that I would be the one to have to fix them when they broke. Whether it was my bicycle or a small toy truck that had a mechanical motor, I always learned exactly how they worked and I came to understand what every single part of the device did, how it related to every other part of the device, and what would be the result if that part broke or malfunctioned.

I remember the first time that I experienced the satisfaction of repairing something by figuring out how to find a suitable replacement for a part that had broken by altering an ordinary household item to perform the right function. Looking back on it, there was not all that much involved, but it was the process of figuring out what was needed, taking stock of what materials were available to me, and then approximating the best possible solution from the materials that were available that I found rewarding.

In the first instance that I remember, an axle broke on a toy fire truck that I enjoyed playing with. First, I tried to repair the broken axle by taping it together...

Next, I tried to fashion a new axle from a straight section of a wire clothes hanger but it was too thick to fit through all of the holes in the truck chassis and in the holes on the wheels. I thought about trying to enlarge all the holes but I realized that some of them were deep inside the frame where it would be impossible for me to reach in order to file them into larger holes.
Next, I tried to find a material that would allow me to trim it easily to the right thickness to fit all the holes that I could not reach. I selected the straightest twig I could find and then I whittled it down to make it perfectly straight and to make it thin enough for my needs. The new wooden axle seemed to work fine when I inserted it through the holes and fastened it to the wheel and I tested it by spinning the wheels and then by rolling the truck around on the floor. Unfortunately, the axle snapped the first time I played with the truck. I examined the broken axle and I also compared the area where it snapped to the truck chassis and I figured out why it happened: the wood was not strong enough to hold up to the sheering force of the metal edge of the holes where it was inserted. At that point, I realized that a new axle would have to be made from metal and not wood and I returned to my original idea of using the piece of wire hanger.

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