First start out with an already build wood freight car. you can choose to purchase one, or build one yourself out of wood.
Step2
Start out with an un-sprung and un-equalized chassis. Make a modification to add springs allow one truck to swing. This will keep all 4 wheels on the rails. But it would cause a lot of frustration if not done properly.
Step3
Install one equalizer beam * The motor used on it can be a 2.5 horsepower 120 volt DC treadmill motor. The controller is a DC to DC converter that operates on 24 volts. It produces 0 to 120 volts DC in 3 transitions
Tips & Warnings
Focus on looking at the pictures it provides a more clearer understanding than the explanation itself
Remember, you will be working with 1 to 2 horsepower on chain and sprocket drives. There will be around 1 kilowatt of electrical power. Use all appropriate safety measures when working with mechanical and electrical systems. Also observe all safety precautions when using tools during construction.
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