This picture shows the construction of the engine. At the bottom is the drive works. The leading truck is built with studs facing down using 12v style black train wheels. The round pieces are mounted facing stud forward. The pieces on the side of the wheels are blue chairs.
The small assembly above the 9v train motor connects rigidly to the assembly above it and the motor pins through it. The middle and front of the boiler is built using stud forward contruction. The rest of the boiler, shown at the top of the image is built in the very traditional stud up configuration.
The entire model is very sturdy and runs very smoothly.
This engine was later rebuilt using BBB train wheels and made into a 4-4-4.
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