Small Engines and Stuff

[Dave R]

[tuna1957]

Very nice ! One question is that a glass cup sticking out of the one end ?

[Dave R]

Thank you. The glass is part of the cylyinder. It gets heated with a flame underneath. The piston is the metal round-ended bit inside.

[Mike Amos]

I agree with t'others, really good to see these.

[Dave R]

@Mike-Amos

Thank you!

[Dave R]

Another machinist's model. A 2 cylinder engine for a paddle steamer with reversing qear. The paddles are articulated so their angle changes as the wheels rotate. Still need to time the valves and properly align the eccentric straps with the eccentrics and of course add screws and nuts.

Rendering straight out SU2026 with a wee bit of simple post processfor the soft shadows and background color.

[tuna1957]

Fantastic. I’m assuming this is a scale model of what was in a full size steamboat. If that’s the case just how big would this wonderful machine have been in full size ?

[Dave R]

Thank you!

Yes. My model is based on a small desktop machinist's model. I believe it was based on a real one but I have no idea how large it would have been.

[Dave R]

Another little engine. These are addictive.

For reference, the flywheels are 100mm diameter.

[Rich O Brien]

Are you gonna shoot the 3I/Atlas as it passes?

[Dave R]

LOL! It does look a little like a cannon.

[Dave R]

Here's a cutaway view.

[Mike Amos]

Amazing little Gems. No doubt.

[Bryan K]

Top notch work as always. Model, style and choice of subjects. Top notch.

[Dave R]

Thank you all.

[Dave R]

Here's a little boxer engine intended to run on compressed air. For reference, the large gear is about 50mm dia.

Like usual I haven't added screws

[Mike Amos]

Pretty sharp, does it have a scavenge system for exhaust into a lower pressure reservoir, a la steam engines?

[Dave R]

Thanks. No scavenger system for the exhaust. It's just dumped out into the room. On the other hand it's only compressed air going in.

[Mike Amos]

Got it, if you can scavenge the exhaust air it can make the process more efficient, hence the three cycle steam engines. At least if I understood Fred anyway.

[Dave R]

A compound steam engine directs the exhaust steam from the first cylinder (smallest one) into the next cylinder which is larger. In the case of a triple expansion engine, a third cylinder (largest of the three) gets the steam from the second cylinder. This works because the steam still has energy to expand after the first and second cylinders. It does require the cylinders get progressively larger.