Air engine

frozenveinz

frozenveinz

New Member
I just hooked up a little 33cc 2 smoker from a stand up scooter to run on 35 psi compressed air. Holy mother of carp. Me torque wrench measures 8 ft/lb at the flywheel, at zero rpm. I would say the max rpm on this bugger has now decreased to maybe 2k tops (With my current trigger system, the motor wants to go faster, but the solenoid won't open fast enough!). But the torque, oh the torque! I can only dream of what higher pressures will bring. Oh wait, I can test too! dance1

When i first flipped the valve, the motor jumped in the air, and flipped once. I need to work on that.

No mods to the engine except replacing the spark plug with a 6v solenoid valve, and replacing the magneto with a reed switch. Wired it up with a 6v lantern battery. Oh, and i removed basically everything but the flywheel, crankcase, and cylinder.

Just did some calculations, and 8 ft/lb @ 2000 RPM equals 3.04 horsepower. From a 33cc motor. At 35 psi. Niiiceeeee

I shall try to plug the exhaust port, and use the intake as the exhaust for a longer power stroke, meaning more power. heheheh I feel like a little kid.
 
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What is the consumption rate? You're gonna need a very big reciever, or a long air hose :)

Tom
 
Not very much, it does not fill the entire cylinder of air, the expansion does not occur throughout the stroke, only as a blast in the beginning. The longer stroke does not use more air, just allows it more space to expand. I would estimate 10-15cc shot of air per down stroke. Based on a 15cc shot and 2000 RPM, which is a pretty optimistic speed, i get 30 liters of air per minute. if i use a wider flywheel, it will use less per stroke, or 2 triggers side by side would make two shots etc etc.

A 24 oz co2 paintball bottle contains about 1,345 Liters of gaseous co2. At 30 L/min, this would last about 45 minutes at 2000 RPM. Using this regulator: http://www.spudtech.com/store/index.php?main_page=product_info&cPath=8&products_id=19 You could attach the co2 bottle to the engine, and go pretty far. Using a 5 inch friction drive roller, strap it to a bike and go 30 mph, for a fuel consumption of 0.9375 miles per oz of liquid co2. This equates to 22.5 miles per 24 oz bottle.

If you carry a 20 lb tank, you could theoretically go 300 miles per fill. Just plan your route with welding supply stores and not gas stations. :D
Likewise a 5lb tank would get you 75 miles, and a 2.5 pound tank would go 37.5 miles.

If you buy an 80 lb tank for 80 or so bucks off craigslist, each $20 fill would equate to 1,200 miles. Just refill your little tank off the big one.

Wow, co2 power is cheaper than gas. Assuming your bike gets 115 mpg, and gas 3.50/gal, 1,200 miles would cost $36.5! thats a $16.5 savings! lol
 
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Don,t let me discourage you , i hope you can prove me wrong .
but i don,t think you will make it to the end of the block let alone 22 miles on a 24 oz bottle of compressed air , c02 , nitrogen .
just think of how much air just an air drill uses .

i like think you are on to something there with the solinoid though ( that will definitely help with the consumption rate )

mabey consider adding in an in line oiler to maintain the engine lubrication and pressure sealing on the rings .

it would be nice to have an extra cylinder to experiment with . since you are just giving it a " jolt " of air with the solenoid , you might want the cylinder to vent ( exaust ) earlier to avoid loss of power to suction , near the bottom of the stroke . ( or try adding some more base gaskets to advance the exaust , just to see what happens )
 
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Air drills use alot of air because they use turbines. Also, I dunno if you know this, but co2 is stored as a liquid, and 24 oz means literally, 24 oz of co2, like a pound and a half.

The solenoid/switching idea is not mine, i got it from STEAM ENGINE TWO STROKE CONVERSION Weed Eater Steam Power - YouTube . I guess i should have said that in the beginning.

Anyway, for lubrication I just spritz in some 2 stroke oil from a mini spray bottle to the crankcase and I drip some into the air stream via a t connector, like doctors use to put stuff into an iv.

Although if using co2, you can pour some oil into the bottle before filling, so that when you fill, the liquid co2 and the oil will mix, and this makes premix. I do this in paintball to keep my gun lubed, works pretty well.
 
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Extremely interesting- got pictures?
Please report back about results.

What if you could run a machine at home to store compressed air daily, or have air filling stations that exchanged canisters?
 
You can also make a plate to put over the intake port, tapped to accept a hose barb and devise a needle valve and hose to an oil resivor. when it's running it will suck oil into the crankcase. I saw a kid do something similar on utube. He didn't have a needle valve, and it sucked up about 3 oz in about 30 seconds.
http://www.youtube.com/watch?v=F28HmBHw5Q4&feature=related

They also have some very efficent designed airmotors that ppl are experimenting with on bicycles. I luv utube :~)
http://www.youtube.com/watch?v=Aec5g0cLt-w&feature=related
I saw some experimental air powered bikes that used scuba tanks for storage. You can buy scuba tank refill compressors on ebay. most are rather expensive new, around 2-3k or more. but used ones are way cheaper.
You can also buy 3000psi surplus millitary aircraft compressors rather cheap. Fighter planes use them on board to pressurise hyd accumulators, and also to blow down the landing gear if they lose their hyd pumps.
 
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I will try to post pics soon. I had an idea though, why not convert a motorized bike to air? The 2 smokers already mounted, and you just replace the magneto/spark plug. Put an air tank in place of gas and voila. But the gear ratios would be way off.
 
Very interesting. While in the Air Force, I had to deal with high press air, 300 lbs and I can tell you the stuff will kill instantly. Saw a rocket rack go into a concrete floor of a hangar about an inch because the snub air did not go to the down side of the actuator . Bad stuff . Keep pressures low I would say but sounds great and you sound like a very informed person. Gonna watch this one and going to Youtube . gphil
 
I think that an oilless compressor would be the best thing off the shelf to convert to an airmotor. The crankcase is totaly unpressurised, so no drag from that like a 2 stroke would have. Or drag from oil splash like a 4 stroke convresion.
No oil needed.
No electric solenoid needed.
Use a cam or piston.bumped valve to inject a burst of air. and a gate valve for throttle.
Dang, I gotta try this!
 
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