I've been wanting to try my hand at making some type of miniature model engine for a long time now. I have seen dozens of these cool videos- in fact, here are two more.
I've built a couple of really simple air engines, and even use the one as a project for my Grade 8 students to build. Here was my first attempt ever at building an engine. This was my test bed for the above engine- basically copied but simplified from one I found on Instructables.
I adapted that one to this one- VERY simple to make and pretty easy to get running decently. ZERO machining- all done on a drill press or with hand tools. Little bit of welding but it could be done without it if you had different chunks of metal.
From this:
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To this:
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Back to the topic at hand. I've got my own idea I've been kicking around for a while- flathead with an atmospheric intake valve, 1" bore and I'm thinking either 1.25 or 1.5" stroke. Not sure how I'm going to do the governor but I've got a few ideas. No idea how well it will work, if it ever even DOES. I don't have a real great track record at finishing projects...
Been working on dumping the ideas swirling around in my head out onto paper and the computer.
Here's the general idea.
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Currently thinking flathead, with atmospheric intake valve. Main design constraints are the limiting factors of the tools I have, so the goal is to make it as simple as possible and entirely built on the tools I have access to- a Smith 1250xl (?) lathe / mill combo. Been playing around a bit and have made some shavings, will get more pics posted.