(Sorry I am pasting my old comment.)
Some Model Engineering related resources:
Engineering drawings of small model engines used in model aircraft making. These designs are intended for manufacturing and practical operation, rather than merely for display, and can be used to build fully functional engines.
https://www.modelengineeringwebsite.com/Beam_Engine_drawings...
https://modelengineeringwebsite.com/Classic_ME_beam_engine.h...
https://outerzone.co.uk/plans.asp?cat=Engines&Xcardsperpage=...
https://modelenginenews.org/midge/index.html
https://modelengineeringwebsite.com/Midget_gas_engine_1.html
https://www.adriansmodelaeroengines.com/catalog/product.php?...
And https://modelengineeringwebsite.com/Classic_ME_beam_engine.h... is almost exactly the CAD model behind this beam engine. Designing that on paper would have been quite a challenge.
(Sorry I am pasting my old comment.)
Some Model Engineering related resources:
Engineering drawings of small model engines used in model aircraft making. These designs are intended for manufacturing and practical operation, rather than merely for display, and can be used to build fully functional engines.
https://www.modelengineeringwebsite.com/Beam_Engine_drawings...
https://modelengineeringwebsite.com/Classic_ME_beam_engine.h...
https://outerzone.co.uk/plans.asp?cat=Engines&Xcardsperpage=...
https://modelenginenews.org/midge/index.html
https://modelengineeringwebsite.com/Midget_gas_engine_1.html
https://www.adriansmodelaeroengines.com/catalog/product.php?...