Air powered motors (r/c)

[Neto_Guima]

Hi all, i dont know if this subject had been discuted, but in the brazilian forum we are tryng to build a motor that run with compressed air or co² just like that one of airhoogs. But R/C.

Had any one try this before ???

Have some ideas, or web links to help.

Tanks all, and sory for my short english, I`m working ont it.

[vintage1]

Co2 motors are very common and available and have been used for free flight and, I think, micro RC for many years.

http://www.gasparin.cz/?show=frames&lng=en

[Sparky Paul]

NASA developed a hydrazine powered plane to fly past the limits imposed on internal combustion motors, using C02 technology..
http://www.dfrc.nasa.gov/gallery/Photo/Mini-Sniffer/HTML/ECN-6134.html
One of the "features" of the system was the life protection gear needed to handle the stuff... :)
I fly r/c with one of the guys that worked on this...

[Neto_Guima]

Co2 motors are very common and available and have been used for free flight and, I think, micro RC for many years.

http://www.gasparin.cz/?show=frames&lng=en


Nice, but they are not for r/c use, becouse they don`t have the throtle, you can`t control the speed, or i`m wrong ??

[Neto_Guima]

sorry, i read it again and i see, that they can be used to R/C too.

http://www.gasparin.cz/?show=frames&site=co2&page=co2/whatsnew/whatsnew&lng=en

[Sparky Paul]

sorry, i read it again and i see, that they can be used to R/C too.

http://www.gasparin.cz/?show=frames&site=co2&page=co2/whatsnew/whatsnew&lng=en
.
I've seen a throttlable CO2 motor on an Aeroenvironment plane, back in 2001 or so. One of those real small... 8" span UAVs those guys make.

[BMatthews]

CO2 is good because it uses a liquid that turns into a gas. But compressed air is far harder to get a good volume at a high pressure without the tank being far too heavy to fly. My scuba tanks hold a whole closet full of air at 3000 psi. But I'd have a hard time making a model to carry the 60 lbs of weight.

There's various model compressed air motors that have been made over the years. One of the more recent was a 3 cylinder motor made from brass tubing and sheet plus a fe lathe turned peices. The tank was a buildup of aluminium pop cans. I've also seen another motor that uses compressed air that used a 2 liter pop bottle that had been wrapped with kevlar tow fiber and epoxy resin to reinforce it. The pop bottle tank reportedly had a working pressure of around 150psi. The pop can tank has a working pressure of around 100 psi. Both were only good for 40 to 60 seconds of run time and far less if the power output was set to a higher level.

[groundfx]

Anybody know what compressed air motor this guy is running? I can't make out what he says.

It seems to work wonderfully.

http://www.youtube.com/watch?v=m7LtAlEyczA

[BMatthews]

I was able to turnup the volume quite a bit thanks to my gaming 5.1 setup. It's a Jonathon (sp?) motor with an 8 inch Stirling prop. The model is 36 inch span and 5 oz.