Pneumatic cannon - Revision history

Saefroch: /* Related Links */

2010-12-13T23:51:47Z

Saefroch: /* Common types of launchers */

2010-12-13T23:51:19Z

Common types of launchers

← Older revision		Revision as of 18:51, 13 December 2010
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	'''Valveless Launchers'''		'''Valveless Launchers'''

	"Valveless" launchers do not have conventional valve, rather the projectile itself is held in the barrel sealing off the pressure chamber, and is fired by physically releasing the projectile. Another variation of the theme is to have the projectile held in a seal that will only release the projectile once a certain pressure is reached. This allows the use of a relatively inefficient slow/low flow valve to fill to the required, while still having maximum performance for the given parameters (zero "opening time" with instantaneous full flow) exceeding any other form of mechanical valve.		"Valveless" launchers do not have conventional valve, rather the projectile itself is held in the barrel sealing off the pressure chamber, and is fired by physically releasing the projectile. Another variation of the theme is to have the projectile held in a seal that will only release the projectile once a certain pressure is reached (commonly referred to as a "detent"). This allows the use of a relatively inefficient slow/low flow valve to fill to the required, while still having maximum performance for the given parameters (zero "opening time" with instantaneous full flow) exceeding any other form of mechanical valve.

	==Related Links==		==Related Links==

Jackssmirkingrevenge: /* Common types of launchers */

2010-12-13T12:19:26Z

Common types of launchers

← Older revision		Revision as of 07:19, 13 December 2010
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	A diaphragm launcher operates on the same principles as a piston valve. The only difference is that the piston cylinder is replaced by a flexible diaphragm that flexes towards the pilot valve to release air into the barrel. These valves open faster than piston valves, but have slightly lower flow rates. While piston valves require a bumper to protect the piston housing, diaphragm valves do not.		A diaphragm launcher operates on the same principles as a piston valve. The only difference is that the piston cylinder is replaced by a flexible diaphragm that flexes towards the pilot valve to release air into the barrel. These valves open faster than piston valves, but have slightly lower flow rates. While piston valves require a bumper to protect the piston housing, diaphragm valves do not.

			'''QEV Launchers'''

	~~'''~~QEV ~~launcher'''~~		[[QEV]] launchers use a similar principle as the [[Piston valve]] only these can be bought from the store. These valves open even faster than piston valves because their [[pilot volume]] is much lower, and the valve is commercially manufactured and optimized.

	~~[[QEV]]~~ launchers use a ~~similar principle as the [[Piston~~ valve~~]] only these can be bought from~~ the ~~store. These valves open even faster than piston valves because their [[pilot volume]] is much lower~~, ~~and~~ the valve ~~is commercially manufactured and optimized~~.		'''Valveless Launchers'''

			"Valveless" launchers do not have conventional valve, rather the projectile itself is held in the barrel sealing off the pressure chamber, and is fired by physically releasing the projectile. Another variation of the theme is to have the projectile held in a seal that will only release the projectile once a certain pressure is reached. This allows the use of a relatively inefficient slow/low flow valve to fill to the required, while still having maximum performance for the given parameters (zero "opening time" with instantaneous full flow) exceeding any other form of mechanical valve.

	==Related Links==		==Related Links==

Technician1002: /* Related Links */

2009-05-12T08:44:30Z

Pilgrimman at 21:10, 4 May 2008

2008-05-04T21:10:45Z

← Older revision		Revision as of 16:10, 4 May 2008
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	[[image:pneumatic ballvalve cannon.jpg\|right\|thumb\|300px\|Pneumatic ball valve cannon]]		[[image:pneumatic ballvalve cannon.jpg\|right\|thumb\|300px\|Pneumatic ball valve cannon]]
	A '''pneumatic cannon''' is a cannon powered by pressurized gas, usually air or CO2. They generally require a little more work to build than [[combustion cannon]]s, but using typical compressor pressures ~~of 120 psig or so~~ and a decent valve, they will outperform most combustion launchers of the same size.		A '''pneumatic cannon''' is a cannon powered by pressurized gas, usually air or CO2. They generally require a little more work to build than [[combustion cannon]]s, but using typical compressor pressures and a decent valve, they will outperform most combustion launchers of the same size.

	==Basic Elements==		==Basic Elements==

Pilgrimman: /* Common types of launchers */

2008-05-04T21:05:41Z

Common types of launchers

← Older revision		Revision as of 16:05, 4 May 2008
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	This is generally an efficient type of launcher, as the opening time is extremely fast and there is very little constriction of airflow in the actual valve. The only real loss of flow can be attributed to the bends inherent in the design that cause gasses to lose energy as they change direction.		This is generally an efficient type of launcher, as the opening time is extremely fast and there is very little constriction of airflow in the actual valve. The only real loss of flow can be attributed to the bends inherent in the design that cause gasses to lose energy as they change direction.

	A diaphragm launcher operates on the same principles as a piston valve. ~~the~~ only difference is that the piston cylinder is replaced by a flexible diaphragm that flexes towards the pilot valve to release air into the barrel. These valves open faster than piston valves, but have slightly lower flow rates. While piston valves require a bumper to protect the piston housing, diaphragm valves do not.		A diaphragm launcher operates on the same principles as a piston valve. The only difference is that the piston cylinder is replaced by a flexible diaphragm that flexes towards the pilot valve to release air into the barrel. These valves open faster than piston valves, but have slightly lower flow rates. While piston valves require a bumper to protect the piston housing, diaphragm valves do not.

Pilgrimman: Added some common launcher info

2008-05-04T21:03:46Z

Added some common launcher info

← Older revision		Revision as of 16:03, 4 May 2008
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	In order to fire, the operator loads a projectile into the barrel, fills the chamber with a compressed gas (see [[Pneumatic air sources]] for common filling methods), and activates the main valve thus dumping the air in the chamber to the barrel.		In order to fire, the operator loads a projectile into the barrel, fills the chamber with a compressed gas (see [[Pneumatic air sources]] for common filling methods), and activates the main valve thus dumping the air in the chamber to the barrel.

	The expansion of the compressed gas propels the projectile down the barrel. The barrel length determines the amount of ~~energy transferred to~~ the projectile and ultimately the velocity of the projectile.		The expansion of the compressed gas propels the projectile down the barrel. The barrel length determines the amount of time the projectile has to accelerate and ultimately the velocity of the projectile.

	Higher performance launchers use techniques such as:		Higher performance launchers use techniques such as:
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	Less common, but also effective in increasing power, some people will also use a gas with a higher speed of sound and particle speed (e.g. helium).		Less common, but also effective in increasing power, some people will also use a gas with a higher speed of sound and particle speed (e.g. helium).

			Efficiency of a cannon can be roughly determined by observing how much noise it makes when fired. A relatively quiet gun is often efficient, as there is little energy left over to create sound.


	==Common types of launchers==		==Common types of launchers==
	~~'''Piston valve launchers'''~~

	[[Piston valve]] launchers use a [[piston]] in a valve that either seals the barrel or chamber. ~~releasing~~ air ~~from~~ the [[pilot valve]] will ~~move~~ the piston away from ~~it's~~ sealing position and air will go out the barrel.		'''Ball Valve Launchers'''

			Ball Valve Launchers release pressurized gas by way of a ball valve. These valves can be made of metal or plastic, and are available in many sizes and pressure ratings. Ball valves are simple to operate, and have very high flow. However, their opening times are comparitively long compared to other valves such as piston valves. Ball valves are typically used in simple designs, or on launchers with long barrels where large airflow is crucial. They can also be used as breech loaders, or venting ports on combustion cannons.

			'''Sprinkler Valve Launchers'''

			Sprinkler Valve Launchers release air using a commercially manufactured sprinkler valve. These valves are simple to use and install, but are designed to open slowly. This is due to their main application in water systems, to prevent water hammer from destroying the valve. Since air is being used, one can modify the valve to actuate faster, using a larger pilot valve, such as a blowgun, without fear of hammer effects. Sprinkler valves are the most cost-effective option if a design calls for moderate performance. However, their relatively low flow rates and number of internal bends cause the performance to reduce to roughly 60% of that of a piston valve of the same diameter. Sprinkler valves are typically rated to ~120 psig, but it is unadvisable to use them at this pressure, as they are designed for use with water.

			'''Piston Valve/Diaphragm Launchers'''

			[[Piston valve]] launchers use a [[piston]] in a valve that either seals against the barrel or chamber. Releasing air through the [[pilot valve]] will cause the remaining air to push the piston away from its sealing position and air will go out the barrel.

			This is generally an efficient type of launcher, as the opening time is extremely fast and there is very little constriction of airflow in the actual valve. The only real loss of flow can be attributed to the bends inherent in the design that cause gasses to lose energy as they change direction.

	~~This is generally an efficient type of~~ launcher, as the ~~opening time~~ is ~~moderately short and there~~ is ~~no choke of airflow in~~ the ~~actual~~ valve.		A diaphragm launcher operates on the same principles as a piston valve. the only difference is that the piston cylinder is replaced by a flexible diaphragm that flexes towards the pilot valve to release air into the barrel. These valves open faster than piston valves, but have slightly lower flow rates. While piston valves require a bumper to protect the piston housing, diaphragm valves do not.


	'''QEV launcher'''		'''QEV launcher'''

	[[QEV]] launchers use a similar principle as the [[Piston valve]] only these can be bought from the store. These valves open even faster than piston valves because their [[pilot volume]] is much lower.		[[QEV]] launchers use a similar principle as the [[Piston valve]] only these can be bought from the store. These valves open even faster than piston valves because their [[pilot volume]] is much lower, and the valve is commercially manufactured and optimized.

	==Related Links==		==Related Links==

	Downloading the [[GGDT]] (Gas Gun Design Tool) is highly recommended to those interested in pneumatic launchers.		Downloading the [[GGDT]] (Gas Gun Design Tool) is highly recommended to those interested in pneumatic launchers.

Necrosis: /* Common types of launchers */

2008-05-04T20:19:31Z

Common types of launchers

← Older revision		Revision as of 15:19, 4 May 2008
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	'''Piston valve launchers'''		'''Piston valve launchers'''

	[[Piston valve]] launchers use a [[piston]]in a valve that either seals the barrel or chamber. releasing air from the ~~back of the~~ valve will ~~set~~ the piston away from it's sealing position and air will go out the barrel.		[[Piston valve]] launchers use a [[piston]] in a valve that either seals the barrel or chamber. releasing air from the [[pilot valve]] will move the piston away from it's sealing position and air will go out the barrel.

			This is generally an efficient type of launcher, as the opening time is moderately short and there is no choke of airflow in the actual valve.

	~~'''More to come'''~~

			'''QEV launcher'''

			[[QEV]] launchers use a similar principle as the [[Piston valve]] only these can be bought from the store. These valves open even faster than piston valves because their [[pilot volume]] is much lower.

	==Related Links==		==Related Links==

	Downloading the [[GGDT]] (Gas Gun Design Tool) is highly recommended to those interested in pneumatic launchers.		Downloading the [[GGDT]] (Gas Gun Design Tool) is highly recommended to those interested in pneumatic launchers.

Necrosis at 20:13, 4 May 2008

2008-05-04T20:13:57Z

← Older revision		Revision as of 15:13, 4 May 2008
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	Less common, but also effective in increasing power, some people will also use a gas with a higher speed of sound and particle speed (e.g. helium).		Less common, but also effective in increasing power, some people will also use a gas with a higher speed of sound and particle speed (e.g. helium).


			==Common types of launchers==
			'''Piston valve launchers'''

			[[Piston valve]] launchers use a [[piston]]in a valve that either seals the barrel or chamber. releasing air from the back of the valve will set the piston away from it's sealing position and air will go out the barrel.


			'''More to come'''


	==Related Links==		==Related Links==

	Downloading the [[GGDT]] (Gas Gun Design Tool) is highly recommended to those interested in pneumatic launchers.		Downloading the [[GGDT]] (Gas Gun Design Tool) is highly recommended to those interested in pneumatic launchers.

Pilgrimman: /* Operation & Theory */

2008-03-09T05:48:58Z

Operation & Theory

← Older revision		Revision as of 00:48, 9 March 2008
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	Higher performance launchers use techniques such as:		Higher performance launchers use techniques such as:
	* Faster valve opening times - see [[sprinkler valve modification]]		* Faster valve opening times - see [[sprinkler valve modification]]
	* Higher flow valves to maximize the airflow through the valve		* Higher flow valves to maximize the airflow through the valve (Especially true for cannons with very long barrels)
	* Using higher gas pressures.		* Using higher gas pressures.
	* Even better, all of the above!

	Less common, but also effective in increasing power, some people will also use a gas with a higher speed of sound and particle speed (e.g. helium).		Less common, but also effective in increasing power, some people will also use a gas with a higher speed of sound and particle speed (e.g. helium).

← Older revision		Revision as of 18:51, 13 December 2010
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	==Related Links==		==Related Links==

	Downloading ~~the~~ [[GGDT]] (Gas Gun Design Tool) is highly recommended to those interested in pneumatic launchers.		Downloading [[GGDT]] (Gas Gun Design Tool) is highly recommended to those interested in pneumatic launchers.

	A page on sprinkler valves and a PDF book can be found here;		A page on sprinkler valves and a PDF book can be found here;
	[http://www.spudfiles.com/spud_wiki/index.php/The_Sprinkler_Valve The Sprinkler Valve]		[http://www.spudfiles.com/spud_wiki/index.php/The_Sprinkler_Valve The Sprinkler Valve]

← Older revision		Revision as of 03:44, 12 May 2009
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	Downloading the [[GGDT]] (Gas Gun Design Tool) is highly recommended to those interested in pneumatic launchers.		Downloading the [[GGDT]] (Gas Gun Design Tool) is highly recommended to those interested in pneumatic launchers.

			A page on sprinkler valves and a PDF book can be found here;
			[http://www.spudfiles.com/spud_wiki/index.php/The_Sprinkler_Valve The Sprinkler Valve]