Models of the Rider Ericsson hot air engine have been popular with model engineers over the years among those with larger workshops, using castings and fabricated construction and most popular in 1:4 scale with a 9” flywheel.
The original engine was developed by Rider in the United States and also became popular in Europe and Australia, finding a wide variety of uses with its quiet and efficient operation.
This nice example from the MEWS archive was built by Philip Bridgway and exhibited at a Bristol exhibition.

MEWS published drawings and build instructions by Jason for an improved  Denny Ericsson engine, starting here.