Combustion cannon - Revision history

Jackssmirkingrevenge: /* Operation & Theory */

2010-12-13T12:27:25Z

Operation & Theory

← Older revision		Revision as of 07:27, 13 December 2010
Line 17:		Line 17:
	In order to fire, the operator loads a projectile (usually a potato) down into the barrel, adds [[fuel]] to the combustion chamber, like spraying [[aerosol]]s in the back end and screwing the cap on and then triggers the [[ignition source]] (e.g. a piezoelectric [[BBQ ignitor]]). The ignition system creates a spark in the chamber which ignites the fuel. The fuel quickly burns up and the hot gases want to expand, creating pressure. The pressure acts as force on the back of the projectile and pushes it rapidly down the barrel. Muzzle velocity and distance vary greatly mostly depending on the [[stoichiometry]] of the fuel/air mixture, the size and [[chamber to barrel ratio]] (C:B ratio) of the launcher and possible performance increasing additions like a [[chamber fan]].		In order to fire, the operator loads a projectile (usually a potato) down into the barrel, adds [[fuel]] to the combustion chamber, like spraying [[aerosol]]s in the back end and screwing the cap on and then triggers the [[ignition source]] (e.g. a piezoelectric [[BBQ ignitor]]). The ignition system creates a spark in the chamber which ignites the fuel. The fuel quickly burns up and the hot gases want to expand, creating pressure. The pressure acts as force on the back of the projectile and pushes it rapidly down the barrel. Muzzle velocity and distance vary greatly mostly depending on the [[stoichiometry]] of the fuel/air mixture, the size and [[chamber to barrel ratio]] (C:B ratio) of the launcher and possible performance increasing additions like a [[chamber fan]].

	The most basic spudguns use aerosols like hairspray, deodorant or [[starting fluid]] sprayed in at the back ([[spray and pray]]), while more advanced cannons usually use [[propane]] injection. Besides the difference of low-power aerosols and pure fuels like propane there is not much of a difference between fuels, the power of propane and butane vary no more then a few percent. Achieving the right stoichiometry (right amount of fuel and air/oxygen) is usually more important for the performance. Spray and pray cannons often have poor stoichiometry and thus inconsistent shots with relatively low power. Fast burning fuels like [[hydrogen]], [[acetylene]] and [[oxygen enriched]] mixtures are usually avoided, even if they may be a little more powerful, their fast burn rates and high chance of [[DDT]] create shockwaves that are powerful enough to rip any PVC or ABS chamber to shreds.		The most basic spudguns use aerosols like hairspray, deodorant or [[starting fluid]] sprayed in at the back ([[spray and pray]]), while more advanced cannons usually use [[propane]] injection. Besides the difference of low-power aerosols and pure fuels like propane there is not much of a difference between fuels, the power of propane and butane vary no more then a few percent. Achieving the right stoichiometry (right amount of fuel and air/oxygen) is usually more important for the performance. Spray and pray cannons often have poor stoichiometry and thus inconsistent shots with relatively low power. Fast burning fuels like [[hydrogen]], [[acetylene]] and [[oxygen enriched]] mixtures are usually avoided, even if they may be a little more powerful, their fast burn rates and high chance of [[DDT]] create shockwaves that are powerful enough to rip any PVC or ABS chamber to shreds.

			The ignition and combustion sequence in a clear barrel/chamber tennis ball launcher can be observed at various speeds in the videos below:

			*[http://www.youtube.com/watch?v=lyqHUM0Aj2k real time]

			*[http://www.youtube.com/watch?v=CyaMRqjAfKo&feature=related 420 frames per second]

			*[http://www.youtube.com/watch?v=6-sahz_GAQE&feature=related 1000 frames per second]

	==Advanced improvements==		==Advanced improvements==

Fnord: minor stuff

2009-03-31T23:17:48Z

minor stuff

← Older revision		Revision as of 18:17, 31 March 2009
Line 1:		Line 1:
	[[image:Basic_combustion.JPG\|right\|thumb\|350px\|Basic combustion cannon]]		[[image:Basic_combustion.JPG\|right\|thumb\|350px\|Basic combustion cannon]]
	A '''combustion cannon''' is a cannon powered by the combustion of flammable fuel-air mixtures. A basic combustion cannon is the simplest one to build, and is therefore often the choice for first time builders, though advanced designs with more power and ~~useability~~ are also possible. Most of the combustion spudguns are made out of [[PVC]] or [[ABS]].		A '''combustion cannon''' is a cannon powered by the combustion of flammable fuel-air mixtures. A basic combustion cannon is the simplest one to build, and is therefore often the choice for first time builders, though advanced designs with more power and usability are also possible. Most of the combustion spudguns are made out of [[PVC]] or [[ABS]].

	Though being the simplest cannon of all, a well-made pneumatic or hybrid is usually more powerful then a combustion. The pressures in a combustion usually do not rise above 50-60 psi on [[spray and pray]] cannons and about 70-90 psi on advanced cannons. Jimmy101, a member of spudfiles showed that in closed chamber experiments the maximum pressure possible with a propane mix is a little more then 100psi in a closed chamber.		Though being the simplest cannon of all, a well-made pneumatic or hybrid is usually more powerful then a combustion. The pressures in a combustion usually do not rise above 50-60 psi on [[spray and pray]] cannons and about 70-90 psi on advanced cannons. Jimmy101, a member of spudfiles showed that in closed chamber experiments the maximum pressure possible with a propane mix is a little more then 100psi in a closed chamber.
Line 15:		Line 15:
	==Operation & Theory==		==Operation & Theory==

	In order to fire, the operator loads a projectile (usually a potato) down into the barrel, adds [[fuel]] to the combustion chamber, like spraying [[aerosol]]s in the back end and screwing the cap on and then triggers the [[ignition source]] (e.g. a piezoelectric [[BBQ ignitor]]). The ignition system creates a spark in the chamber ~~wich~~ ignites the fuel. The fuel quickly burns up and the hot gases want to expand, creating pressure. The pressure acts ~~out~~ force on the back of the projectile and ~~the air~~ pushes the ~~projectile out~~. Muzzle velocity and distance vary greatly mostly depending on the [[stoichiometry]] of the fuel/air mixture, the size and [[chamber to barrel ratio]] (C:B ratio) of the launcher and possible performance increasing additions like a [[chamber fan]].		In order to fire, the operator loads a projectile (usually a potato) down into the barrel, adds [[fuel]] to the combustion chamber, like spraying [[aerosol]]s in the back end and screwing the cap on and then triggers the [[ignition source]] (e.g. a piezoelectric [[BBQ ignitor]]). The ignition system creates a spark in the chamber which ignites the fuel. The fuel quickly burns up and the hot gases want to expand, creating pressure. The pressure acts as force on the back of the projectile and pushes it rapidly down the barrel. Muzzle velocity and distance vary greatly mostly depending on the [[stoichiometry]] of the fuel/air mixture, the size and [[chamber to barrel ratio]] (C:B ratio) of the launcher and possible performance increasing additions like a [[chamber fan]].

	The most basic spudguns use aerosols like hairspray, deodorant or [[starting fluid]] sprayed in at the back ([[spray and pray]]), while more advanced cannons usually use [[propane]] injection. Besides the difference of low-power aerosols and pure fuels like propane there is not much of a difference between fuels, the power of propane and butane vary no more then a few percent. Achieving the right stoichiometry (right amount of fuel and air/oxygen) is usually more important for the performance. Spray and pray cannons often have poor stoichiometry and thus inconsistent shots with relatively low power. Fast burning fuels like [[hydrogen]], [[acetylene]] and [[oxygen enriched]] mixtures are usually avoided, even if they may be a little more powerful, their fast burn rates and high chance of [[DDT]] create shockwaves that are powerful enough to rip any PVC or ABS chamber to shreds.		The most basic spudguns use aerosols like hairspray, deodorant or [[starting fluid]] sprayed in at the back ([[spray and pray]]), while more advanced cannons usually use [[propane]] injection. Besides the difference of low-power aerosols and pure fuels like propane there is not much of a difference between fuels, the power of propane and butane vary no more then a few percent. Achieving the right stoichiometry (right amount of fuel and air/oxygen) is usually more important for the performance. Spray and pray cannons often have poor stoichiometry and thus inconsistent shots with relatively low power. Fast burning fuels like [[hydrogen]], [[acetylene]] and [[oxygen enriched]] mixtures are usually avoided, even if they may be a little more powerful, their fast burn rates and high chance of [[DDT]] create shockwaves that are powerful enough to rip any PVC or ABS chamber to shreds.
Line 28:		Line 28:
	*[[Breech loading]] mechanism		*[[Breech loading]] mechanism

	The above improvements will increase the power and/or ~~useability~~ of the gun. View those pages for more information.		The above improvements will increase the power and/or usability of the gun. View those pages for more information.

	==Safety==		==Safety==
Line 35:		Line 35:
	When using a normal fuel, pressure rated pipe and fittings and have properly [[solvent welding\|solvent welded]] all of the joints, you can be considered 100% safe.		When using a normal fuel, pressure rated pipe and fittings and have properly [[solvent welding\|solvent welded]] all of the joints, you can be considered 100% safe.

	Some people, like parents think it is unsafe because it is an "explosion" and thus dangerous. In that case point them on the facts that it is just a [[deflagration]] and not a [[detonation]] creating no huge shockwaves, but creating just heat and pressure. This pressure is lower then the rated pressure of pressure rated pipe and fittings and that means the gun simply can't explode.		Some people, like parents, think it is unsafe because it is an "explosion" and thus dangerous. In that case point them on the facts that it is just a [[deflagration]] and not a [[detonation]] creating no huge shockwaves, but creating just heat and pressure. This pressure is lower then the rated pressure of pressure rated pipe and fittings and that means the gun simply can't explode.

	Note that cold weather makes pvc brittle and you should not use a frozen gun. However a gun that has been frozen some time but is up to normal temperature again is safe to use.		Note that cold weather makes pvc brittle and you should not use a frozen gun. However a gun that has been frozen some time but is up to normal temperature again is safe to use.

Benstern: fixed link

2008-06-14T20:47:15Z

fixed link

← Older revision		Revision as of 15:47, 14 June 2008
Line 22:		Line 22:

	*[[Chamber fan]]		*[[Chamber fan]]
	*[[Stun gun]], [[flyback transformer]] or [[camera flash]] ignition		*[[Stun gun]], [[Flyback circuit\|flyback transformer]] or [[camera flash]] ignition
	*Multiple [[spark gap]]s		*Multiple [[spark gap]]s
	*[[Fuel meter]]		*[[Fuel meter]]

Psycix: spelling, link, and one interpunction

2008-06-03T20:58:02Z

spelling, link, and one interpunction

← Older revision		Revision as of 15:58, 3 June 2008
Line 1:		Line 1:
	[[image:Basic_combustion.JPG\|right\|thumb\|350px\|Basic combustion cannon]]		[[image:Basic_combustion.JPG\|right\|thumb\|350px\|Basic combustion cannon]]
	A '''combustion cannon''' is a cannon powered by the combustion of flammable fuel-air mixtures. A basic combustion cannon is the simplest one to build, and is therefore often the choice for first time builders, though advanced designs with more power and useability are also possible. Most of the combustion spudguns are made out of [[PVC]] or [[ABS]]		A '''combustion cannon''' is a cannon powered by the combustion of flammable fuel-air mixtures. A basic combustion cannon is the simplest one to build, and is therefore often the choice for first time builders, though advanced designs with more power and useability are also possible. Most of the combustion spudguns are made out of [[PVC]] or [[ABS]].

	Though being the simplest cannon of all, a well-made pneumatic or hybrid is usually more powerful then a combustion. The pressures in a combustion usually do not rise above 50-60 psi on [[spray and pray]] cannons and about 70-90 psi on advanced cannons. Jimmy101, a member of spudfiles showed that in closed chamber experiments the maximum pressure possible with a propane mix is a little more then 100psi in a closed chamber.		Though being the simplest cannon of all, a well-made pneumatic or hybrid is usually more powerful then a combustion. The pressures in a combustion usually do not rise above 50-60 psi on [[spray and pray]] cannons and about 70-90 psi on advanced cannons. Jimmy101, a member of spudfiles showed that in closed chamber experiments the maximum pressure possible with a propane mix is a little more then 100psi in a closed chamber.
Line 17:		Line 17:
	In order to fire, the operator loads a projectile (usually a potato) down into the barrel, adds [[fuel]] to the combustion chamber, like spraying [[aerosol]]s in the back end and screwing the cap on and then triggers the [[ignition source]] (e.g. a piezoelectric [[BBQ ignitor]]). The ignition system creates a spark in the chamber wich ignites the fuel. The fuel quickly burns up and the hot gases want to expand, creating pressure. The pressure acts out force on the back of the projectile and the air pushes the projectile out. Muzzle velocity and distance vary greatly mostly depending on the [[stoichiometry]] of the fuel/air mixture, the size and [[chamber to barrel ratio]] (C:B ratio) of the launcher and possible performance increasing additions like a [[chamber fan]].		In order to fire, the operator loads a projectile (usually a potato) down into the barrel, adds [[fuel]] to the combustion chamber, like spraying [[aerosol]]s in the back end and screwing the cap on and then triggers the [[ignition source]] (e.g. a piezoelectric [[BBQ ignitor]]). The ignition system creates a spark in the chamber wich ignites the fuel. The fuel quickly burns up and the hot gases want to expand, creating pressure. The pressure acts out force on the back of the projectile and the air pushes the projectile out. Muzzle velocity and distance vary greatly mostly depending on the [[stoichiometry]] of the fuel/air mixture, the size and [[chamber to barrel ratio]] (C:B ratio) of the launcher and possible performance increasing additions like a [[chamber fan]].

	The most basic spudguns use aerosols like hairspray, deodorant or ~~starter~~ fluid sprayed in at the back ([[spray and pray]]), while more advanced cannons usually use [[propane]] injection. Besides the difference of low-power aerosols and pure fuels like propane there is not much of a difference between fuels, the power of propane and butane vary no more then a few percent. Achieving the right stoichiometry (right amount of fuel and air/oxygen) is usually more important for the performance. Spray and pray cannons often have poor stoichiometry and thus inconsistent shots with relatively low power. Fast burning fuels like [[hydrogen]], [[acetylene]] and [[oxygen enriched]] mixtures are usually avoided, even if they may be a little more powerful, their fast burn rates and high chance of [[DDT]] create shockwaves that are powerful enough to rip any PVC or ABS chamber to shreds.		The most basic spudguns use aerosols like hairspray, deodorant or [[starting fluid]] sprayed in at the back ([[spray and pray]]), while more advanced cannons usually use [[propane]] injection. Besides the difference of low-power aerosols and pure fuels like propane there is not much of a difference between fuels, the power of propane and butane vary no more then a few percent. Achieving the right stoichiometry (right amount of fuel and air/oxygen) is usually more important for the performance. Spray and pray cannons often have poor stoichiometry and thus inconsistent shots with relatively low power. Fast burning fuels like [[hydrogen]], [[acetylene]] and [[oxygen enriched]] mixtures are usually avoided, even if they may be a little more powerful, their fast burn rates and high chance of [[DDT]] create shockwaves that are powerful enough to rip any PVC or ABS chamber to shreds.

	==Advanced improvements==		==Advanced improvements==

Psycix: Revamped the whole page.

2008-06-03T14:25:25Z

Revamped the whole page.

← Older revision		Revision as of 09:25, 3 June 2008
Line 1:		Line 1:
	[[image:Basic_combustion.JPG\|right\|thumb\|350px\|Basic combustion cannon]]		[[image:Basic_combustion.JPG\|right\|thumb\|350px\|Basic combustion cannon]]
	A '''combustion cannon''' is a cannon powered by the combustion of flammable fuel-air mixtures. A basic combustion cannon is the simplest one to build, and is therefore often the choice for first time builders.		A '''combustion cannon''' is a cannon powered by the combustion of flammable fuel-air mixtures. A basic combustion cannon is the simplest one to build, and is therefore often the choice for first time builders, though advanced designs with more power and useability are also possible. Most of the combustion spudguns are made out of [[PVC]] or [[ABS]]

	==Basic elements==		Though being the simplest cannon of all, a well-made pneumatic or hybrid is usually more powerful then a combustion. The pressures in a combustion usually do not rise above 50-60 psi on [[spray and pray]] cannons and about 70-90 psi on advanced cannons. Jimmy101, a member of spudfiles showed that in closed chamber experiments the maximum pressure possible with a propane mix is a little more then 100psi in a closed chamber.

	* ~~Fuel System~~		Potato guns are often painted to increase their aesthetic value and to cover unsightly primer stains. Krylon Fusion, a type of paint specifically made for plastics, is the most common type of spray paint used on potato cannons. Some combustion cannons have chambers made from clear pvc, this allows you to see the internals like the sparks and the fan (LED fans can be beautiful this way) and most importantly: a flash of fire on ignition.
	* ~~Combustion~~ [[~~Chamber~~]]
	* [[Ignition source]]		==Basic elements==
	* [[Barrel]]
			* Combustion [[Chamber]]
	==Operation & Theory==		* [[Fuel]]
			* [[Ignition source]]
	In order to fire, the operator loads a projectile (usually a potato) into the barrel, adds [[fuel]] to the combustion chamber ~~(for example~~ [[aerosol]]s ~~or [[propane]]),~~ and triggers the [[ignition source]] (e.g. a piezoelectric [[BBQ ignitor]]). The fuel ~~should then ignite, create~~ hot ~~expanding~~ gases, and ~~force~~ the projectile out ~~of the barrel~~. ~~Distances~~ vary greatly depending on ~~the type of fuel used and~~ the [[stoichiometry]] of the fuel/air mixture, the size and [[chamber to barrel ratio]] (C:B ratio) of the launcher~~; 100 meters is~~ a ~~common distance~~.		* [[Barrel]]

	~~A common question from beginning spudders is "'''What is~~ the ~~best fuel"'''? This can be a rather controversial topic but see~~ [[~~Common Fuels for Combustion Spudguns~~]] ~~for~~ a ~~reasonably comprehensive discussion~~ of ~~many~~ of the ~~common spudgun~~ fuels.		==Operation & Theory==

	~~Improvements on the basic combustion launcher include optimized C:B ratios~~, [[~~fuel meter\|metered propane~~]] ~~injection~~, [[chamber fan]]s, ~~multiple~~ [[~~spark gap~~]]~~s (~~[[~~spark strip~~]]~~s), and high voltage~~ ignition ~~sources (~~[[~~flyback circuit~~]]s, [[~~stun gun~~]]s, [[~~camera flash~~]]~~es, etc). Combustion launchers are mechanically simple, but are less powerful in typical situations~~* ~~compared to a~~ [[~~pneumatic cannon\|pneumatic launcher~~]] of the ~~same size~~. ~~Potato guns are often painted to increase their aesthetic value and to cover unsightly primer stains. Krylon Fusion, a type of paint specifically made~~ for ~~plastics, is the most common type of spray paint used on potato cannons~~.		In order to fire, the operator loads a projectile (usually a potato) down into the barrel, adds [[fuel]] to the combustion chamber, like spraying [[aerosol]]s in the back end and screwing the cap on and then triggers the [[ignition source]] (e.g. a piezoelectric [[BBQ ignitor]]). The ignition system creates a spark in the chamber wich ignites the fuel. The fuel quickly burns up and the hot gases want to expand, creating pressure. The pressure acts out force on the back of the projectile and the air pushes the projectile out. Muzzle velocity and distance vary greatly mostly depending on the [[stoichiometry]] of the fuel/air mixture, the size and [[chamber to barrel ratio]] (C:B ratio) of the launcher and possible performance increasing additions like a [[chamber fan]].

	~~'''Combustion safety '''~~		The most basic spudguns use aerosols like hairspray, deodorant or starter fluid sprayed in at the back ([[spray and pray]]), while more advanced cannons usually use [[propane]] injection. Besides the difference of low-power aerosols and pure fuels like propane there is not much of a difference between fuels, the power of propane and butane vary no more then a few percent. Achieving the right stoichiometry (right amount of fuel and air/oxygen) is usually more important for the performance. Spray and pray cannons often have poor stoichiometry and thus inconsistent shots with relatively low power. Fast burning fuels like [[hydrogen]], [[acetylene]] and [[oxygen enriched]] mixtures are usually avoided, even if they may be a little more powerful, their fast burn rates and high chance of [[DDT]] create shockwaves that are powerful enough to rip any PVC or ABS chamber to shreds.
	Non pressure rated pipe is generally ~~excepted as~~ safe with ~~combustions but~~ pressure rated pipe ~~is alway preferable~~.
	specific fuels such as [[acetylene]], hydrogen, and any oxygen enriched ~~mixture~~. ~~They create~~ [[~~pressure~~]]~~s not suitable for any plastic chamber and could cause an explosion~~.		==Advanced improvements==

	~~<nowiki>*</nowiki>The mass of the projectile~~ is ~~high enough~~ that the ~~faster cannon~~ is not ~~"solely" decided by~~ the ~~speed~~ of ~~sound in the gas~~ and the ~~flow of the valve,~~ and ~~low enough~~ that ~~these things still matter~~. ~~This will include almost any projectile you~~'~~ll ever shoot~~.		*[[Chamber fan]]
			*[[Stun gun]], [[flyback transformer]] or [[camera flash]] ignition
	==~~Related links~~==		*Multiple [[spark gap]]s
	[[~~Miniature spudguns~~]]		*[[Fuel meter]]
			*A good [[C:B ratio]]
			*[[Breech loading]] mechanism

			The above improvements will increase the power and/or useability of the gun. View those pages for more information.

			==Safety==
			Non [[pressure rated]] "DWV" pipe is used so now and then in combustion cannons and it is generally accepted that this is safe with basic spray and pray; however some of these cannons have blown up. If you want to be safe you should definitely use pressure rated pipe and fittings, especially on advanced combustions.
			As stated above specific fuels such as acetylene, hydrogen, and any oxygen enriched mixtures are not safe to use in a gun made out of PVC or ABS.
			When using a normal fuel, pressure rated pipe and fittings and have properly [[solvent welding\|solvent welded]] all of the joints, you can be considered 100% safe.

			Some people, like parents think it is unsafe because it is an "explosion" and thus dangerous. In that case point them on the facts that it is just a [[deflagration]] and not a [[detonation]] creating no huge shockwaves, but creating just heat and pressure. This pressure is lower then the rated pressure of pressure rated pipe and fittings and that means the gun simply can't explode.

			Note that cold weather makes pvc brittle and you should not use a frozen gun. However a gun that has been frozen some time but is up to normal temperature again is safe to use.
			Dropping the gun isn't recommended, especially frozen guns, since this might create tiny cracks; a starting point for completely cracking open and blowing up.

			==Legality==
			Laws are different in each country, state or even city, check the [[legal issues]] page for more information. In some countries combustion cannons are illegal while pneumatics (possibly being way more powerful) may be legal.

Benstern: added links and fixed spelling

2008-06-01T11:10:20Z

added links and fixed spelling

← Older revision		Revision as of 06:10, 1 June 2008
Line 15:		Line 15:
	A common question from beginning spudders is "'''What is the best fuel"'''? This can be a rather controversial topic but see [[Common Fuels for Combustion Spudguns]] for a reasonably comprehensive discussion of many of the common spudgun fuels.		A common question from beginning spudders is "'''What is the best fuel"'''? This can be a rather controversial topic but see [[Common Fuels for Combustion Spudguns]] for a reasonably comprehensive discussion of many of the common spudgun fuels.

	Improvements on the basic combustion launcher include optimized C:B ratios, [[fuel meter\|metered propane]] injection, [[chamber fan]]s, multiple [[spark gap]]s ([[spark strip]]s), and high voltage ignition sources ([[flyback circuit]]s, [[stun gun]]s, [[camera flash]]es, etc). Combustion launchers are mechanically simple, but are less powerful in typical situations* compared to a pneumatic launcher of the same size. Potato guns are often painted to increase their aesthetic value and to cover unsightly primer stains. Krylon Fusion, a type of paint specifically made for plastics, is the most common type of spray paint used on potato cannons.		Improvements on the basic combustion launcher include optimized C:B ratios, [[fuel meter\|metered propane]] injection, [[chamber fan]]s, multiple [[spark gap]]s ([[spark strip]]s), and high voltage ignition sources ([[flyback circuit]]s, [[stun gun]]s, [[camera flash]]es, etc). Combustion launchers are mechanically simple, but are less powerful in typical situations* compared to a [[pneumatic cannon\|pneumatic launcher]] of the same size. Potato guns are often painted to increase their aesthetic value and to cover unsightly primer stains. Krylon Fusion, a type of paint specifically made for plastics, is the most common type of spray paint used on potato cannons.

	'''Combustion safety '''		'''Combustion safety '''
	Non pressure rated pipe is generally excepted as safe with combustions but pressure rated pipe is alway ~~prefferable~~.		Non pressure rated pipe is generally excepted as safe with combustions but pressure rated pipe is alway preferable.
	specific fuels such as ~~acetelene~~, hydrogen, and any oxygen ~~inriched~~ mixture. They create ~~pressures~~ not suitable for any plastic chamber and could cause an explosion.		specific fuels such as [[acetylene]], hydrogen, and any oxygen enriched mixture. They create [[pressure]]s not suitable for any plastic chamber and could cause an explosion.

	<nowiki>*</nowiki>The mass of the projectile is high enough that the faster cannon is not "solely" decided by the speed sound in the gas and the flow of the valve, and low enough that these things still matter. This will include almost any projectile you'll ever shoot.		<nowiki>*</nowiki>The mass of the projectile is high enough that the faster cannon is not "solely" decided by the speed of sound in the gas and the flow of the valve, and low enough that these things still matter. This will include almost any projectile you'll ever shoot.

	==Related links==		==Related links==
	[[Miniature spudguns]]		[[Miniature spudguns]]

Jimmy101: Removed Bigbob's comment about "simplest", see the discussion page

2008-03-09T18:40:51Z

Removed Bigbob's comment about "simplest", see the discussion page

← Older revision		Revision as of 13:40, 9 March 2008
Line 1:		Line 1:
	[[image:Basic_combustion.JPG\|right\|thumb\|350px\|Basic combustion cannon]]		[[image:Basic_combustion.JPG\|right\|thumb\|350px\|Basic combustion cannon]]
	A '''combustion cannon''' is a cannon powered by the combustion of flammable fuel-air mixtures. A basic combustion cannon is the simplest one to build, and is therefore often the choice for first time builders.		A '''combustion cannon''' is a cannon powered by the combustion of flammable fuel-air mixtures. A basic combustion cannon is the simplest one to build, and is therefore often the choice for first time builders.
	~~bigbob edit, above it says they are the simplest to build this is not true. Pnuematics are much easier to build and oprerate.~~

	==Basic elements==		==Basic elements==

Bigbob12345 at 16:35, 9 March 2008

2008-03-09T16:35:28Z

← Older revision		Revision as of 11:35, 9 March 2008
Line 1:		Line 1:
	[[image:Basic_combustion.JPG\|right\|thumb\|350px\|Basic combustion cannon]]		[[image:Basic_combustion.JPG\|right\|thumb\|350px\|Basic combustion cannon]]
	A '''combustion cannon''' is a cannon powered by the combustion of flammable fuel-air mixtures. A basic combustion cannon is the simplest one to build, and is therefore often the choice for first time builders.		A '''combustion cannon''' is a cannon powered by the combustion of flammable fuel-air mixtures. A basic combustion cannon is the simplest one to build, and is therefore often the choice for first time builders.
			bigbob edit, above it says they are the simplest to build this is not true. Pnuematics are much easier to build and oprerate.

	==Basic elements==		==Basic elements==
Line 16:		Line 17:

	Improvements on the basic combustion launcher include optimized C:B ratios, [[fuel meter\|metered propane]] injection, [[chamber fan]]s, multiple [[spark gap]]s ([[spark strip]]s), and high voltage ignition sources ([[flyback circuit]]s, [[stun gun]]s, [[camera flash]]es, etc). Combustion launchers are mechanically simple, but are less powerful in typical situations* compared to a pneumatic launcher of the same size. Potato guns are often painted to increase their aesthetic value and to cover unsightly primer stains. Krylon Fusion, a type of paint specifically made for plastics, is the most common type of spray paint used on potato cannons.		Improvements on the basic combustion launcher include optimized C:B ratios, [[fuel meter\|metered propane]] injection, [[chamber fan]]s, multiple [[spark gap]]s ([[spark strip]]s), and high voltage ignition sources ([[flyback circuit]]s, [[stun gun]]s, [[camera flash]]es, etc). Combustion launchers are mechanically simple, but are less powerful in typical situations* compared to a pneumatic launcher of the same size. Potato guns are often painted to increase their aesthetic value and to cover unsightly primer stains. Krylon Fusion, a type of paint specifically made for plastics, is the most common type of spray paint used on potato cannons.

			'''Combustion safety '''
			Non pressure rated pipe is generally excepted as safe with combustions but pressure rated pipe is alway prefferable.
			specific fuels such as acetelene, hydrogen, and any oxygen inriched mixture. They create pressures not suitable for any plastic chamber and could cause an explosion.

	<nowiki>*</nowiki>The mass of the projectile is high enough that the faster cannon is not "solely" decided by the speed sound in the gas and the flow of the valve, and low enough that these things still matter. This will include almost any projectile you'll ever shoot.		<nowiki>*</nowiki>The mass of the projectile is high enough that the faster cannon is not "solely" decided by the speed sound in the gas and the flow of the valve, and low enough that these things still matter. This will include almost any projectile you'll ever shoot.

Ragnarok at 17:50, 15 February 2008

2008-02-15T17:50:39Z

← Older revision		Revision as of 12:50, 15 February 2008
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	A '''combustion cannon''' is a cannon powered by the combustion of flammable fuel-air mixtures. A basic combustion cannon is the simplest one to build, and is therefore often the choice for first time builders.		A '''combustion cannon''' is a cannon powered by the combustion of flammable fuel-air mixtures. A basic combustion cannon is the simplest one to build, and is therefore often the choice for first time builders.

	~~Combustion powered spudguns have four basic~~ elements:		==Basic elements==

	* Fuel System		* Fuel System
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	* [[Barrel]]		* [[Barrel]]

			==Operation & Theory==

	In order to fire, the operator loads a projectile (usually a potato) into the barrel, adds [[fuel]] to the combustion chamber (for example [[aerosol]]s or [[propane]]), and triggers the [[ignition source]] (e.g. a piezoelectric [[BBQ ignitor]]). The fuel should then ignite, create hot expanding gases, and force the projectile out of the barrel. Distances vary greatly depending on the type of fuel used and the [[stoichiometry]] of the fuel/air mixture, the size and [[chamber to barrel ratio]] (C:B ratio) of the launcher; 100 meters is a common distance.		In order to fire, the operator loads a projectile (usually a potato) into the barrel, adds [[fuel]] to the combustion chamber (for example [[aerosol]]s or [[propane]]), and triggers the [[ignition source]] (e.g. a piezoelectric [[BBQ ignitor]]). The fuel should then ignite, create hot expanding gases, and force the projectile out of the barrel. Distances vary greatly depending on the type of fuel used and the [[stoichiometry]] of the fuel/air mixture, the size and [[chamber to barrel ratio]] (C:B ratio) of the launcher; 100 meters is a common distance.
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	Improvements on the basic combustion launcher include optimized C:B ratios, [[fuel meter\|metered propane]] injection, [[chamber fan]]s, multiple [[spark gap]]s ([[spark strip]]s), and high voltage ignition sources ([[flyback circuit]]s, [[stun gun]]s, [[camera flash]]es, etc). Combustion launchers are mechanically simple, but are less powerful in typical situations* compared to a pneumatic launcher of the same size. Potato guns are often painted to increase their aesthetic value and to cover unsightly primer stains. Krylon Fusion, a type of paint specifically made for plastics, is the most common type of spray paint used on potato cannons.		Improvements on the basic combustion launcher include optimized C:B ratios, [[fuel meter\|metered propane]] injection, [[chamber fan]]s, multiple [[spark gap]]s ([[spark strip]]s), and high voltage ignition sources ([[flyback circuit]]s, [[stun gun]]s, [[camera flash]]es, etc). Combustion launchers are mechanically simple, but are less powerful in typical situations* compared to a pneumatic launcher of the same size. Potato guns are often painted to increase their aesthetic value and to cover unsightly primer stains. Krylon Fusion, a type of paint specifically made for plastics, is the most common type of spray paint used on potato cannons.

	<nowiki>*) </nowiki>~~the~~ mass of the projectile is high enough that the faster cannon is not "solely" decided by the speed sound in the gas and the flow of the valve, and low enough that these things still matter. This will include almost any projectile you'll ever shoot.		<nowiki>*</nowiki>The mass of the projectile is high enough that the faster cannon is not "solely" decided by the speed sound in the gas and the flow of the valve, and low enough that these things still matter. This will include almost any projectile you'll ever shoot.

			==Related links==
			[[Miniature spudguns]]

Benstern: spelling

2007-06-03T05:31:47Z

spelling

← Older revision		Revision as of 00:31, 3 June 2007
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	In order to fire, the operator loads a projectile (usually a potato) into the barrel, adds [[fuel]] to the combustion chamber (for example [[aerosol]]s or [[propane]]), and triggers the [[ignition source]] (e.g. a piezoelectric [[BBQ ignitor]]). The fuel should then ignite, create hot expanding gases, and force the projectile out of the barrel. Distances vary greatly depending on the type of fuel used and the [[stoichiometry]] of the fuel/air mixture, the size and [[chamber to barrel ratio]] (C:B ratio) of the launcher; 100 ~~metres~~ is a common distance.		In order to fire, the operator loads a projectile (usually a potato) into the barrel, adds [[fuel]] to the combustion chamber (for example [[aerosol]]s or [[propane]]), and triggers the [[ignition source]] (e.g. a piezoelectric [[BBQ ignitor]]). The fuel should then ignite, create hot expanding gases, and force the projectile out of the barrel. Distances vary greatly depending on the type of fuel used and the [[stoichiometry]] of the fuel/air mixture, the size and [[chamber to barrel ratio]] (C:B ratio) of the launcher; 100 meters is a common distance.

	A common question from beginning ~~spuders~~ is "'''What is the best fuel"'''? This can be a rather controversial topic but see [[Common Fuels for Combustion Spudguns]] for a reasonably comprehensive discussion of many of the common spudgun fuels.		A common question from beginning spudders is "'''What is the best fuel"'''? This can be a rather controversial topic but see [[Common Fuels for Combustion Spudguns]] for a reasonably comprehensive discussion of many of the common spudgun fuels.

	Improvements on the basic combustion launcher include optimized C:B ratios, [[fuel meter\|metered propane]] injection, [[chamber fan]]s, multiple [[spark gap]]s ([[spark strip]]s), and high voltage ignition sources ([[flyback circuit]]s, [[stun gun]]s, [[camera flash]]es, etc). Combustion launchers are mechanically simple, but are less powerful in typical situations* compared to a pneumatic launcher of the same size. Potato guns are often painted to increase their aesthetic value and to cover unsightly primer stains. Krylon Fusion, a type of paint specifically made for plastics, is the most common type of spray paint used on potato cannons.		Improvements on the basic combustion launcher include optimized C:B ratios, [[fuel meter\|metered propane]] injection, [[chamber fan]]s, multiple [[spark gap]]s ([[spark strip]]s), and high voltage ignition sources ([[flyback circuit]]s, [[stun gun]]s, [[camera flash]]es, etc). Combustion launchers are mechanically simple, but are less powerful in typical situations* compared to a pneumatic launcher of the same size. Potato guns are often painted to increase their aesthetic value and to cover unsightly primer stains. Krylon Fusion, a type of paint specifically made for plastics, is the most common type of spray paint used on potato cannons.

	<nowiki>*) </nowiki>the mass of the projectile is high enough that the faster cannon is not "solely" decided by the speed sound in the gas and the flow of the valve, and low enough that these things still matter. This will include almost any projectile you'll ever shoot.		<nowiki>*) </nowiki>the mass of the projectile is high enough that the faster cannon is not "solely" decided by the speed sound in the gas and the flow of the valve, and low enough that these things still matter. This will include almost any projectile you'll ever shoot.