Just as an interest I'll post a picture of one of my collection then.
This was an Ebay purchase a year or so ago and it has been made from a set of plans and a series of articles published in a model engineering magazine of about 1964. I was actually able to get hold of back copies of the six magazines with all the articles in them which surprised me to say the least.
Anyway the model is a four cylinder engine, or, more accurately, two twin cylinder opposed piston engines. As you can see opposite pistons are connected together via the copper con rods which turn the crank via the two crossheads mounted on the flywheel. The pistons are only single acting but with four cylinders the engine is still self starting and could be made reversible and controllable if a reversing steam control valve was fitted.
I would love to mount this engine in a boat but it is a bit too big and the centre of gravity very high. It would be best done with a belt drive to a pulley on the prop shaft with the engine mounted transversely across the hull.
The other down side is that it uses quite a bit of air from my air brush compressor to get it going so it would need a fair size boiler to propel a boat. To see it all spin around though is quite hypnotic and I just get it going every now and then for the sheer pleasure of watching it.
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“Dirty British coaster with a salt-caked smoke stack, Butting through the Channel in the mad March days" |