Or you could wrap tape around the axles and motor so gears and wheels fit....fleet130 wrote:Finding parts is ALWAYS a problem! Fitting parts together is part of what engineering is all about. Building events competitions are not just about building the project. Figuring out HOW to build the project, including choosing what parts to use, is a major portion.
Choosing parts is almost always a trade-off between what's optimum and availability, time, effort, money, skill and other factors. If you're short in one or more areas, you can often compensate by expending more of another. One common mistake is trying to compensate for all with money. This may sometimes work in the Science Olympiad scenario, but it isn't always viable in the real world. Expending a little more time and effort can often reduce cost significantly.
The magnitude of the problem can be reduced by using a motor, transmission, wheel and axle obtained as an assembly. Drive axles salvaged from battery operated/radio control vehicles are one source. They can be purchased new for $5 (sometimes less) from toy stores. Robotics and educational science material suppliers are another source or parts. Tamiya manufactures several gearbox/motor combinations suitable for this event. The Tamiya gearboxes are lightly built, so you will need to keep overall vehicle weight down or they may wear out quickly. These same suppliers often have wheels made to fit on the transmission's axle.
Be sure to "try before you buy". This means gathering as much information as you can and figuring out how the parts will fit together, before you put out any money. No matter how much you plan, there will be times where you just can't make the parts you bought work. Save them in your parts box and they may be useful in a later project.
Search the internet to find out what parts exist, then with a little more work you can discover what's available within the resources you have.
Tape is definitely helping me in building the Battery Buggy. Tape ftw
