[peterfirefly]

Despite all the details, you still left out a lot. Safety valve, pressure gauge(s), regulation of the water pump, water level gauge for the boiler, lubrication (you only have two of the glass/metal can reservoir types for the main axle), and then maybe also the valve gear (the control mechanism for the valves which takes into account where in the cycle the machine is and maybe also how fast it is going, how fast it should be going, and in which direction). And a way to drain water from the bottom of the cylinder + maybe a way to make the steam as dry as possible.

And each of those could be expanded to much more than the page you already made.

Things are almost always a lot more complicated than they seem. It seems so simple -- "water + heat makes steam, steam pushes piston, back and forth motion makes rotary motion" -- but it is really anything but.

[glinscott]

RE: Things are more complicated - I totally agree. My favorite part of the article is probably the belt transmission section. I wasn't sure how it was possible for a leather belt to transmit so much power. Super fun to just dig in deeper and deeper to see how it works. Even there though, I left out a lot - the material properties of leather that let it work, how they attached the belts, the problems they had with gears transmitting power (partly leading to the development of the involute shape for gears), etc.

RE: safety valve, pressure gauge, etc. - yes, there is definitely another article to be built here :). Another fun aspect is safely starting the machine, warming it up appropriately, flushing water from the system, and the bigger engines even had a small engine to get the wheel turning.

[peterfirefly]

Bearings is another good subject to dive into.

> I wasn't sure how it was possible for a leather belt to transmit so much power.

Friction is also one of the main reasons why rivets work. And why ropes work and why knots don't unwind and lashings work and, and, and ... and of course also nails and screws and worm drives. Friction is awesome.

> Another fun aspect is safely starting the machine

I saw them start this little beaty more than a decade ago:

https://dieselhouse.dk/en/videnom/#BW2000

It was not exactly a quick and simple job.