I 3D Printed a Liquid Piston Engine

3D Models

#rotary #engine #3dprinting

[flamedude_]

The magnet might make the spinning part unbalanced so either balance it or make a valve that is driven from the output shaft.

[made]

You can try to lighter the shaft and change the magnet sensor to a light sensor ( diode).

Tomatoes are disgusting!

[noobcrafterz]

Since the rotor is symmetrical, put magnets on both sides, that way each valve is triggered twice a rotation. In theory this should produce twice the power and your motor will run smoother

[deejayskyce]

A tip, instead of sanding the parts when it's a rotary friction use an abrasive compound like a 600 or 1000 grit lapping paste and then work up to a polishing grit. Just put it on the surfaces making contact and spin it normally assembled for a few minutes. Clean and replace compound every few minutes and don't worry about parts staying rigidly against each others, lateral movement will make for a better removal and polish. Might take 15 20 minutes but you can potentially end up with thousandths of an inch tolerances or even more precise with technique. Then you can get away with no lubricant as long as the parts don't start moving out of tolerance from wear elsewhere.

[afterthewar]

I think you could do two things relatively easily to improve the engine’s power - first use an encoder on the output shaft to monitor the rotor position and use an MCU to control the air or ignition in each cylinder. That way you can also easily and repeatably adjust timing for maximum power.

Second, use inlets for all three chambers to maximize power generation. I think the timing method is the most important change for maximizing power though.

[laurasoffientini]

Video idea: Can you make rocket with a thrust vector control similar to spacex falcon 1? With a couple of linear actuators and an arduino controller it should be doable

[tando]

Something to keep in mind is that the co2 goes through a non adiabatic expansion in the Chamber which causes cooling in the system, causing a drop in efficiency after each activation. Switching back to high pressure air will give you better efficiency for longer durations

[carloscampos]

With a hall sensor you can monitor the position and speed of each rotation, allowing you to fine tune for the optimal point to open the solenoids and for how long. You can even use a potentiometer to shorten the duration of each pulse so you can control the engine speed

[williamcampbell]

Hi integza, with the magnet on only one side of the rotor, you're only firing the "cylinder" at a 50% duty cycle - it could be firing for the other side of the rotor too. with a magnet on each side of the rotor and with gas hooked up to all 3 "cylinders" (lobes?) you would be able to get better torque and more power!

Edit: like this comment so he sees!

[JustinEdwardsL]

Read the position of the shaft for your valve timing instead of magnets on the piston, might also need a small flywheel to smooth it out.

[Nosonuk]

Improvement ideas: Remove the magnets from the piston and change to optical sensors on the axial shaft. The sensors could use beam-break on a disc that would act as a flywheel.

[nickrosfelder]

You can use a timing belt to have the valves time properly and use a third hole to eliminate any lag in the system

[tsbrownie]

To mate moving parts with close tolerances, you can use grinding compound and lap the parts (grind against each other in place).

[jameslmorehead]

For making clear resin parts clear, and to lubricate them, I've found it very handy to sand then up to 800 grit sand paper, then buff the parts with Dow Corning 111. DC111 is sold as an oring lubricant, but being silicon based keeps it from degrading the 3D prints and greatly reduces friction. It also has a high surface tension, so it stays in place very well.

If you don't want a lubricant on the surface, another great way to make clear parts clear is with Novas 123. It's a multi step plastic polish that also works great on aged headlight lenses.

[Malkawi_FTP]

You can actually use steel because it has less friction
and easier to seal.
and place another pair of magnets in the opposite end of the rotar to get twice the pulses in each round which means more power,
and you can make some chambers in the casing that has some oiling mechanism to reduce friction as much as you can.

[musicforeveryone]

at 10:35, we can see that an other "combustion" on the other side of the rotating piece is possible just before the magnetic switch turns on. and this maybe by adding a magnet on the other side. so it will also balance correctly the piece and help the engine to run better

[stephenashdown]

Great video! The pilot valve has a small port restricting flow. Try a bigger port 3/2 valve as the valve you are using is just for pilot signals and not flow. Also try adding a small air lubricator to the supply airflow, the droplets of oil will assist in sealing.

[HartenDylan]

I'm sure this has already been suggested, but a second pair of magnets would balance the rotational assembly while giving you two power pulses per rotation. Smoother power delivery, and likely reduce the gear lash from asymmetrical pulses! Great video, interested to see where you go with it.

[BassBoostedDuck]

There are some issues with the current solution of your engine (sadly), BUT i can write up a few things you can change!
For starters your still only using half its potential power, if you put magnets on the other side of the rotor as well, then you'll get twice the output, i would also suggest making gasket to get a better use of the compressed air.
Another thing you can do is make an ECU (electronic control unit), this would allow for control of the timings of the valves just like in a real car, this allows you to control how fast you want the engine to spin as well as how long each valve is open and closed, this can be done by adding an raspberry pi to see what Eletro magnet switch is on at what point and check how long it takes for it to reach the next one.
doing this could also allow for data output into graphs to allow you to see the power spikes along with its rotation speed. This is one of the things i would of done on many of your old projects as you have a tendency to make them all run as fast as they can without any control.
Not only does this shorten the life span of the engine but it also doesn't help if you cant control the engine, as it would just be a glorified spinner with no way to control it.

Most engines need to start with low speed with high torque and get higher and higher speeds as time goes on with less and less torque as its already up to speed. this would help combat the friction you keep getting stuck with and it will also help when you put a load onto the output ether to generate power or to spin something. hope this helps.

I have also send you an email so hopefully you'll see this i used to study this at college as well as do it as my job but in the last two years i have moved into game creation and i love 3D printing my projects so that's how i came across your channel. (although i only have a half broken 3D printer that is very small, lol).
I would love to have a chat with you about this sometime and give you a hand so let me know.

[kj]

Since you use compressed air so much in your videos I think an interesting idea for a future video would be a 3D printed air compressor! You could power it with an electric motor or for some extra fun, a gas turbine!