The interactive article is so good!

(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?...