Boil Off Some White Gas in the Back Yard


[S Heath] is a Coleman lantern collector. Coleman lanterns can run from a variety of fuels, however they seem to run best with white gas, or Coleman fuel. Store bought Coleman fuel can cost upwards of $10USD/gallon. To keep the prices down, [S Heath] has created a still in his back yard to purify pump gas. We just want to take a second to say that this is not only one of those hacks that we wouldn’t want you to try at home, it’s also one that we wouldn’t try at home ourselves. Heating gasoline up past 120 degrees Celsius in a (mostly) closed container sounds like a recipe for disaster. [S Heath] has pulled it off though.

The still is a relatively standard setup. An electric hot plate is used to heat a metal tank. A column filled with broken glass (increased surface area for reflux) rises out of the tank. The vaporized liquid that does make it to the top of the column travels through a condenser – a pipe cooled with a water jacket. The purified gas then drips out for collection. The heart the system is a PID controller. A K-type thermocouple enters the still at the top of the reflux column. This thermocouple gives feedback to a PID controller at the Still’s control panel. The controller keeps the system at a set temperature, ensuring consistent operation. From 4000 mL of ethanol free pump gas, [S Heath] was able to generate 3100 mL of purified gas, and 500 mL of useless “dregs”. The missing 400 mL is mostly butane dissolved in the pump gas, which is expelled as fumes during the distillation process.

Continue reading “Boil Off Some White Gas in the Back Yard”

Four-stroke engine with glass cylinder is a 2400 RPM piece of art

We know a lot about toggling bits in a register, but only a bit about how engines work. This one inspires us to throw ourselves into the field with reckless abandon. [Huib Visser] built this glass cylinder four-stroke engine and he took great care to make it beautiful. We don’t need our projects to be polished and gleaming, but we have to admit that this the opposite of what we see when popping the hood on our 12-year-old rust bucket out front.

You can’t see it in this image, but just on the other side of the fly-wheel is a smaller wheel with a cord wrapped around it that acts as the pull start. This gets the toothed timing belt going along with the cylinder. As part of the demo video we get a good look at how the rotary intake and exhaust valves work. [Huib] also took the time to demonstrate how the rare earth magnets and hall effect sensor reed switch synchronize the ignition system.

You won’t want to miss the end of the video which show it in action as It burns Coleman fuel (white gas) and is lubricated with WD-40. This is jaw dropping and it works like a charm, but still not that far removed from the concepts seen in [Lou’s] hardware store engine project.

UPDATE: Here’s write up this engine (translated) [Thanks ChalkBored]

Continue reading “Four-stroke engine with glass cylinder is a 2400 RPM piece of art”