the design for my first combustion

Boom! The classic potato gun harnesses the combustion of flammable vapor. Show us your combustion spud gun and discuss fuels, ratios, safety, ignition systems, tools, and more.
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hoastmaster
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Fri Jun 22, 2007 5:56 am

chamber:
20cm diameter (outside)
50cm lenght

barrel:
150cm lenght
5cm diameter (outside)

ignition:
9 volt car battery-charge coil-automotive spark plug

fuel:
airosole spry maybe lynx (due to hight alchole content)

if i get it right ill try methanol in mist form (squirted into chamber with squidgy bottle like the ones with window cleaner in them)Image
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MrCrowley
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Fri Jun 22, 2007 6:11 am

Just letting you know you will be paying about $100NZD for a 200mm - 50mm reducer and even more for a clean out cap. For a cheap cost effective gun that should be safe with hairspray get,

Chamber: 500mmx100mm(dia) DWV PVC pipe
A 100mm Clean out cap
A 100mmx50mm Recducer/bushing
and glue and prime all of that together and your barrel.

That will cost you about $150NZD all up as cleanout caps will cost you about $30-40 and buying the 100mm pipe will cost you a bit as well, then you need to buy primer and a reducer on top of that. I know our prices are crazy wait till you get into pneumatics with Pressure Rated fittings.
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hoastmaster
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Fri Jun 22, 2007 6:19 am

its ok i my dad can get the parts for me through his work and itll cost me a fraction

the reason im going for thease particular sizes is for the methanol mist combustion theory

it needs lots of air and makes big presure so the sizes are all good but i might make the chamber i bit smaller
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lukemc
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Fri Jun 22, 2007 7:45 am

hoastmaster wrote:its ok i my dad can get the parts for me through his work and itll cost me a fraction

the reason im going for thease particular sizes is for the methanol mist combustion theory

it needs lots of air and makes big presure so the sizes are all good but i might make the chamber i bit smaller
lucky. from my dad at work i can only get electric motors and o rings...
"Those who are different change the world. Those who are the same keep it that way"
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noname
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Fri Jun 22, 2007 10:35 am

Sounds pretty good, but isn't 200 mm like, humongoginormous? I plugged into Google and got 7.87 inches. Pretty big pipe, it's not going to be cheap.

Lukemc, be glad you can get anything cheap from your parents' jobs. Mine are both teachers. :?
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hoastmaster
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Sun Jun 24, 2007 12:19 am

the plan is for a mix of fuels im going to concoct using some knowledge of chemistry and so teenage injanuity (lol) as my choice of fuel

i came across a web page on fuel combustion and basicly i can make a simpler form of tri poxy hexane wich is like using jet fuel and liquid nitrogen together

so need big barrel and big chamber because small one not going to be good for oxygen needs
IE explosion sucks tater bake down pipe itill it implodes or air is found and explodes
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