SpudFiles Wiki - User contributions [en]

Barrel

2006-02-03T03:02:48Z

71.136.47.52:

The '''barrel''' is the pipe used to launch the projectile, and is, along with the [[chamber]], the only component found in all launchers. The diameter determines what projectiles will fit in the launcher, and the length affects how much energy is transferred to the projectile.

Modifications and improvements to the basic barrel include [[sleeving]], [[rifled barrel|rifling]], [[hop-up]]s and flatline barrels.

There are many diameters of barrels popular in spudding, below are some that fit certain ammo:

* 4.5mm brakeline - fits bbs, good for [[BBMGs]]
* 6mm brakeline - fits airsoft bbs, a commonly used ammo in BBMGs.
* 3/4" CPVC, 3/4" sch 80 PVC (looser fit), or 3/4" sch 120 PVC - fits .68" paintballs
* 1/2" sch 40 PVC - fits AA batteries, marbles.
* 3/4" sch 40 PVC - fits 12g [[CO2 cartridge]]s, C batteries.
* 1" sch 40 PVC - C batteries, smaller sized bouncy balls.
* 1.25" sch 40 PVC - D fits somesort of battery
* 1.5" sch 40 PVC - a common size, good trade-off between power and potato usage. [http://www.spudtech.com/components.asp Available rifled from the [[SGTC]]]
* 1.5" sdr 21 PVC - fits golfballs. Traditionally [[sleeving|sleeved]] within SCH-80 PVC.
* 1.5" sdr 26 PVC - fits golfballs, but it is thinner than sdr 21, so the golfballs fit a little looser. Traditionally sleeved within 2" SCH-80 PVC.
* 2" sch 40 PVC fits caulk tubes and potatoes. you have to get some huge baking potatoes though.
* 2" sch 80 PVC fits 1.5" nominal pipe well, making it ideal for [[sleeving]] Also used as a golf ball barrel by itself, with the golf ball held in place by a rag patch, or other wadding. Also fits normal light bulbs! Details [http://advancedspuds.com/concreteballs.htm here].
* 2.5" sch 40 PVC - fits tennis balls well.
* 3" sch 80 PVC - fits many drink bottles well.
* 3" sch 40 PVC - fits normal cans, and empty propane torch tanks
* 4" sch 40 PVC - fits 29 oz. cans
[[Category:Components]]

User:PCGUY

2006-02-03T03:00:50Z

71.136.47.52:

A pimp.

A 1337 h4xx0r pimp.

Burst disk

2006-02-01T18:13:49Z

71.136.47.52:

A burst disk ruptures when the pressure gets to a certain point, allowing the gas to propel the projectile down the [[barrel]]. Due to this method of "opening", they have the fastest [[opening time]] of any valve in existence. They are nearly always used for [[hybrid cannon|hybrids]], and occasionaly as the main valve in a [[pneumatic cannon]].

They are a very close rival to a ball valve in cost, at roughly 13$ for a 2" [[union]] in sch 40 PVC. More expensive (but conveinent) devices exist, such as [[cam lever coupling]]s.
To use, [[solvent welding|solvent weld]] your chamber to one half of your union or cam coupling. One then 'loads' the valve by putting a layer of some weak material (such as multiple layers of aluminum foil, or a piece of a beverage container) in between the 2 halves of the union or coupling. The union or cam coupling is then tightened down, locking the disk of [[burst disk material]] in place.

In a hybrid cannon, burst disks fail when the pressure builds due to the combusting gasses. Prior to this, chamber was containing the flammable gasses at a relatively low pressure. They are also sometimes used on [[combustion cannon]]s - for their noisemaking capabilities, and/or their ([http://www.advancedspuds.com/burstdisk.htm debated]) performance improvement.

In a pneumatic cannon, they can be used in the same way, simply pointing the cannon in the correct direction and filling it until it fires. However, many opt to use another system because of the inherent safety issues with this. Such systems include puncturing it with a pointy object (such as a nail) attaced to the end of the projectile, melting it with an electrically heated wire, and a pneumatically [[triggered burst disk]] system using dual burst disks.

[[category:valves]]

Burst disk

2006-02-01T18:13:13Z

71.136.47.52:

A burst disk ruptures when the pressure gets to a certain point, allowing the gas to propel the projectile down the [[barrel]]. Due to this method of "opening", they have the fastest [[opening time]] of any valve in existence. They are nearly always used for [[hybrid cannon|hybrids]], and occasionaly as the main valve in a [[pneumatic cannon]].

They are a very close rival to a ball valve in cost, at roughly 13$ for a 2" [[union]] in sch 40 PVC. More expensive (but conveinent) devices exist, such as [[cam lever coupling]]s.
To use, [[solvent welding|solvent weld]] your chamber to one half of your union or cam coupling. One then 'loads' the valve by putting a layer of some weak material (such as multiple layers of aluminum foil, or a piece of a beverage container) in between the 2 halves of the union or coupling. The union or cam coupling is then tightened down, locking the disk of [[material]] in place.

In a hybrid cannon, burst disks fail when the pressure builds due to the combusting gasses. Prior to this, chamber was containing the flammable gasses at a relatively low pressure. They are also sometimes used on [[combustion cannon]]s - for their noisemaking capabilities, and/or their ([http://www.advancedspuds.com/burstdisk.htm debated]) performance improvement.

In a pneumatic cannon, they can be used in the same way, simply pointing the cannon in the correct direction and filling it until it fires. However, many opt to use another system because of the inherent safety issues with this. Such systems include puncturing it with a pointy object (such as a nail) attaced to the end of the projectile, melting it with an electrically heated wire, and a pneumatically [[triggered burst disk]] system using dual burst disks.

[[category:valves]]

Supah-Valve

2006-02-01T18:12:44Z

71.136.47.52:

The Supah-Valve is a chamber sealing piston valve designed and made by the[[The Spudgun Technology Center]]. To date it is the best performing spudgunning valve on the market. Their opening time is second only to a [[burst disk]] They are designed to work with compressed gases and are handmade. They have a excellent reputation and the quality is like nothing else. They are made from 3" PVC tees.

[[Image:sv1.jpg]]

'''Specifications:'''
*Maximum Pressure - 120 psi
*2" porting (inlet and outlet holes)
*Nitrile O-ring sealed with nitrile face-gasket (1)
*static and dynamic bulkheads (1)

sources: (1)[http://web.archive.org/web/19960101000000-20030101235959/http://www.spudtech.com/supahvalveprod.html an old spudtech page]

[[category:valves]]

Supah-Valve

2006-02-01T18:12:29Z

71.136.47.52:

The Supah-Valve is a chamber sealing piston valve designed and made by the[[The Spudgun Technology Center]]. To date it is the best performing spudgunning valve on the market. Their opening time is second only to a [[burst-disk]] They are designed to work with compressed gases and are handmade. They have a excellent reputation and the quality is like nothing else. They are made from 3" PVC tees.

[[Image:sv1.jpg]]

'''Specifications:'''
*Maximum Pressure - 120 psi
*2" porting (inlet and outlet holes)
*Nitrile O-ring sealed with nitrile face-gasket (1)
*static and dynamic bulkheads (1)

sources: (1)[http://web.archive.org/web/19960101000000-20030101235959/http://www.spudtech.com/supahvalveprod.html an old spudtech page]

[[category:valves]]

BBQ ignitor

2006-02-01T18:07:57Z

71.136.47.52:

[[Image:BBQ_Ignitor.jpg|right|thumb|250px|A simple piezo ignitor for a grill]]A '''BBQ ignitor''' or grill ignitor is arguably the simplest spudgun [[ignition source]]. It consists of a pushbutton, that activates a hammer mechanism that strikes a piezoelectric crystal. The crystal generates a high voltage pulse that can be made to jump a small spark gap. One of the main advantages to a BBQ ignitor is that it doesn't use batteries, and is cheap and relatively small. Quality differs quite a bit though, some ignitors last for many years while other break after some time of use. The spark is also the weakest of the common ignition sources, and achieving ignition may take several attempts in some circumstances (cold weather, sub-optimal fuel mixes, etc).
Piezoelectric ignitors can also be obtained from a few other devices, notably long-nosed lighters, and some gas ignitors and cigarette lighters.

There are also electric BBQ ignitors that run on a 1.5V or 9V battery. They are weak compared to other electronic [[ignition source]]s, but a good choice for remote ignition.
[[Category:Ingition sources]]

Barrel

2006-02-01T18:05:52Z

71.136.47.52:

Sleeving

2006-02-01T18:03:26Z

71.136.47.52:

==Reasons==
<b>Sleeving</b> is a method of reinforcing pipe, typically thinwall [[PVC pipe]], by placing it inside a larger diameter pipe. For sleeving to be efficient, the outer diameter of the inner pipe needs to closely match the inner diameter of the outer pipe.

Another reason for sleeving barrels is to create more appropriate diameters for specific projectiles. For instance, if the barrel inside diameter is 2.00" and you have a slightly smaller projectile, another PVC barrel could be inserted inside the 2.00" diameter barrel. The resulting smaller diameter barrel would be an apprporiate size for a golf-ball or other unusual projectile.

==Methods==
===Direct insertion===
Sometimes, there is a pipe diameter that matches the pipe you want to sleeve close enough to directly insert it. For instance, 1.5" nominal fits very well in 2" sch 80. Often it it glued, normaly with a relitvly slow-curing glue. However, the force required to cause the pipe to move sometimes makes this overkill.

===modifed insert===
This is used in the situation that the pipe you want to insert is too big to do so.
Simply, a lengthwise section of the pipe is removed, allowing the diameter of the insert to be reduced. With much effort, it is then possible to shove this into the outer pipe; the effort required to do so is great enough that glueing it is unneeded.

{{stub}}

Hybrid cannon

2006-01-19T04:26:24Z

71.136.47.52:

A '''hybrid''' launcher consists of seven basic elements:

*High pressure combustion chamber
*Pressure-triggered main valve (usually a [[burst disk]])
*[[Barrel]]
*Fuel system (usually [[fuel meter|metered propane]])
*Air filling valve
*powerful [[Ignition source]]
*One or more [[pressure gauge]]s

A hybrid is a type of spudgun that combines principles of the [[combustion cannon|combustion]] and [[pneumatic cannon|pneumatic]] spudgun. It uses a pressurized mixture of fuel and air to get more power out of a given chamber volume. In order to fire, the operator first inserts a [[burst disk]], usually consisting of aluminium foil or plastic, between the chamber and barrel. A [[Cam lever coupling]] or [[union]] is used to hold the burst disk in place. The operator then loads projectile into the barrel, adds fuel to the combustion chamber, and then adds pressurized air. The amount of air depends on how much fuel was added, and is calculated to achieve a [[stoichiometric]] fuel/air ratio in the chamber. when the ignition source is triggered, the pressure from the combustion ruptures the burst disk and propels the projectile out of the barrel. The hybrid is capable of higher velocities than a combustion or pneumatic spudgun, projectiles fired by a hybrid have broken the sound barrier (Source). A hybrid using twice as much fuel and air as a comparable combustion gun is said to be using a 2X mix, higher mixtures can be used and will produce even higher pressures. The fuel and air needs to be measured and matched carefully to ensure reliable operation, pressure gauges and fuel meters are used for this. A pressure gauge with a check valve can also be added to record the peak chamber pressure of the gun.

===Safety===
A hybrid is the most dangerous launcher that can be built. It is advised to build with pipe that can handle the high pressure environment (200+ [[Pressure gauge|PSI]]) such as Sch. 80 PVC or metal. Remote ignition is a must, and the limit of a 4x propane/ 4 atmosphere mix should never be breached. If a higher mix is attempted, DDT (deflagration to detonation transition) can occur, causing an extreme pressure spike. Most pipe cannot handle the spike, and will shatter, launching plastic shards every where. Therefore utmost care must be taken with these launchers.