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Engine

Posted: Mon Feb 25, 2008 4:41 pm
by pat123
Over the summer I am thinking about trying to make a piston that can drive a gocart size vehicle. I know people have posted about this and most pass it off as a bad idea that won't work, but i think i can make it work. it will be atleast sch 40 steel pipe. I will be using butane as my fuel. In my animation, the place where the fuel comes in should be lower and the exhaust point should be higher. please leave comments.

edit: I can't post the animation so i just added a pic

Posted: Mon Feb 25, 2008 5:48 pm
by ShowNoMercy
Why not just try and replicate a two stroke engine? I think I would be much easier.

Posted: Mon Feb 25, 2008 6:13 pm
by pat123
more like this? http://www.keveney.com/twostroke.html

so do you think butane will be sufficient or should i use something else?

Posted: Mon Feb 25, 2008 6:44 pm
by tomthebomb137
What you bassically have here is a 2 stroke engine in its simplest form, instead of having the piston compress the fuel/air in the crankcase, you have that switch to open the vavle, and becaseu you are using butane it is already under compression, but youve forgotten a very important element that being the lubrication, and in a 2 stroke engine this is injected into the fuel, but as you are using a compressed gas, this will be pretty hard to accomplish, and also 1 thing to remeber, a 2 stroke engine is a very violent peice of machinery as it is firing every revolution at a very high RPM, so any imperfection in your design and build can cause cause bad things to happen, sometimes very bad things. But your on the right track man :D

Posted: Mon Feb 25, 2008 6:50 pm
by pat123
thanks for the help. So would you go with my design or the one i linked to? And what type of pipe should i use? will steel hold all of the smashing of the piston, i think it should.

Posted: Mon Feb 25, 2008 11:43 pm
by FeLeX
You know if you take any type of engine and feed propane through air intake it will work? You will have to tweak with it a little bit but it will work. Look it up. There are cars all around the world that run on propane because it lets you go farther and its cheaper. Make google your buddy.

Posted: Tue Feb 26, 2008 9:58 am
by pat123
yeah its not just having a propane engine , I want to build my own.

Posted: Tue Feb 26, 2008 1:44 pm
by Sticky_Tape
I think you should make a pneumatic engine.
This is a engine I designed in class today it doesn't seem too hard to make and you could have a port at the top to let oil in I think a pneumatic engine would be more interesting than a propane engine it's quieter and 0 emision oh yes the engine would be a single stroke
the second engine would be larger.

Posted: Tue Feb 26, 2008 2:22 pm
by Jared Haehnel
Think of your dentist the drill he uses to bore through your tooth is run on compressed air. A miniature turbine is basically what it is. The problem with compresses air is its high speed, low torque.
So what ever you used would have to use a very high pressure gas or be geared down very low. Then you'd have to spend the energy to pressurize the tank... What you have is basically a compressor in reverse.

Good thought....

Posted: Tue Feb 26, 2008 3:02 pm
by jackssmirkingrevenge
I think you should make a pneumatic engine.
This is how most piston engines running on compressed gas work:

Image

Unless you had a high pressure source like a SCUBA tank or similar, suitable regulated, it wouldn't be a practical form of power, considering the specs of modern air car developments.

Posted: Tue Feb 26, 2008 3:08 pm
by tomthebomb137
jared you have an intersting point, if you want think of it like a pnuematic impact wrench cause theyre high torque, high speed :twisted: But if you are going to build an internal combustion, i would house the pipe in something like a milled out brick of metal for added saftey especially since this engine might be moving someone in it

Posted: Tue Feb 26, 2008 3:24 pm
by Jared Haehnel
Your right I hadn't thought of that application all the one I could think of were low torque, high speed and were basically, turbines. I guess I poses the question are torque guns direct drive or do they have gear boxes?

Something like what Jack has could be easily converted to steam power... which would be way more powerful then running off compressed air. A bit more dangerous too...

Posted: Tue Feb 26, 2008 4:09 pm
by Fnord
Something like what Jack has could be easily converted to steam power... which would be way more powerful then running off compressed air. A bit more dangerous too...
Come to think of it, Why couldn't the heat from an internal combustion engine be used to run a boiler instead of being blown out the exhaust pipe/radiator?

Posted: Tue Feb 26, 2008 4:14 pm
by Jared Haehnel
I read a report about a guy developing a six cycle engine. After the normal combustion of a four stroke there was another cycle where water was sprayed onto the hot cylinder to flash off into steam. Kind of like a Stanly steamer. It was projected to increase mpg by 40 percent. I think it was in popular science...

Posted: Tue Feb 26, 2008 4:14 pm
by SpudMonster
_Fnord wrote:
Something like what Jack has could be easily converted to steam power... which would be way more powerful then running off compressed air. A bit more dangerous too...
Come to think of it, Why couldn't the heat from an internal combustion engine be used to run a boiler instead of being blown out the exhaust pipe/radiator?
Too much weight, what the fuck do you do with the steam generated (add a turbine/reciprocating engine into the mix and you get more weight), too dangerous (boilers are quite upkeep-intensive if you want to keep them safe) too complicated due to condensate/oil separation, feedwater pumps, makeup water supply, pop valve, feedwater regulation, the list goes on and on...