Rotary Valve Engine Gets A Second Chance, Smokes The Competition

February 21, 2022 by Ryan Flowers 42 Comments

It’s a dedicated hacker who has the patience to build an engine from scratch. And it’s a borderline obsessed hacker who does it twice. [Meanwhile In the Garage] is of the second ilk, and in the video below the break, he takes a failed engine design and musters up the oomph to get it running.

The whole build began with an idea for a different kind of intake and exhaust valve. [Meanwhile In the Garage] dreamed up a design that does away with the traditional poppet valve. Instead of valves that open by being pushed away from their seat by a camshaft, this design uses a cylinder that is scooped so that as it rotates, its ports are exposed to either the intake or the exhaust.

Four Stroke Cycle with Poppet valves. Courtesy Wikipedia, CC BY-SA 3.0

During the compression stroke, the valve cylinder becomes part of the combustion chamber, with both ports facing away from the piston. If you read the comments, you’ll find that multiple people have come up with the idea through the years. With his mill, lathe, and know-how, [Meanwhile In the Garage] made it happen. But not without some trouble.

The first iteration resisted all valiant attempts at getting it started. The hour-long video preceding this one ended up in a no-start. Despite his beautiful machine work and a well thought out design, it wasn’t to be. Fire came from the engine either through the exhaust or the carburetor, but it never ran. In this version, several parts have been re-worked and the effect is immediate! The engine fired up nicely and even seems to rev up pretty well. Being a first-generation prototype, it lacks seals and other fancy parts to keep oil out of the combustion chamber. Normal engine oil has been added to the fuel as a precaution as well. The fact that it smokes quite badly isn’t a surprise and only proves that the design will benefit from another iteration. Isn’t that true for most prototypes, though?

Home-grown engines aren’t a new thing at Hackaday, and one of This Author’s favorite jet turbines used a toilet paper holder. Yes, really. Thanks to [Keith] for the Tip!

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Homemade Internal Combustion Engine – Sans Machine Shop

December 22, 2015 by George Graves 18 Comments

We’ve got a question for you: If you were stuck in a basement, with nothing too much more than some copper pipe, solder, JB-Weld, and a few hand tools, do you think you could make a working 2-stroke motor? Well, [Makerj101] did just that, and the results are fan-freaking-tastic.

[Makerj101] began his journey like most of us do – with a full face-plant type failure. His first attempted at building an internal combustion engine wouldn’t run, due to a low compression ratio, and too small port sizes. So he did what most of us would do, and tore apart a small gas-power weed-whacker motor to see what he was doing wrong.

The type of engine he’s making is a 2-stroke. That makes the design much simpler as there are no mechanically controlled valves a like 4-stroke motor. The piston (along with the cylinder wall) does double duty by also directing the intake and exhaust gasses – along with a simple flap-type check valve.

For now, the ignition system is run off of mains power, but he has plans to change that – creating a self contained engine. We’re amazed that the entire build is made with such simple tools. Even the the piston is cast out of “JB Weld” epoxy putty. After seeing this, we think that the kid who took apart a clock is going to have to up his game a bit.

We’ve included all 6 parts after the break.

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Almost Building An Engine From Hardware Store Parts

December 14, 2012 by Brian Benchoff 82 Comments

engine

You can build a surprising amount of stuff from parts you can pick up at a hardware store. Sometimes, though, getting a project built from sections of pipe is very, very difficult. That’s the case with [Lou]’s hardware store engine: despite an inordinate amount of cleverness, he just can’t seem to get an engine made from pipe fitting to work and is now asking for some ideas from other ingenious makers.

The engine uses regular oxygen and propane tanks you can pick up at Home Depot with torch heads soldered onto half inch pipe. The fuel and oxygen are mixed in a T fitting until a grill igniter sets the gas mixture ablaze pushing a cylinder down the length of a copper pipe. The cylinder is attached to an aluminum flywheel that also controls the opening and closing of the oxygen and propane valves as well as switching the grill igniter on and off.

Right now, [Lou] can get the engine running, but only for one stroke of the cylinder. He’s having a bit of a problem turning this into a working motor. If you’ve got any idea on how to make [Lou]’s engine work, drop a line in the comments. We’ll throw our two cents in and say he needs a valve on the exhaust, but other suggestions are always welcome.