SpudFiles Wiki - User contributions [en]

Compression fitting

2007-01-27T12:03:28Z

LucyInTheSky:

Compression fittings are mainly used on copper pipe, they are very simle in the way they work. An olive, a small ring of bras not unlike in appearence to a wedding ring, fits over the copper pipe. Then when the fitting around it is tightened they will deform the olive so it grips the pipe.
Compression fittings are usually stronger than solder fittings by a small margin but are harder to airtight and dont look as nice. Compression fittings are also alot more expensive, some as much as 3 times more expensive in larger copper sizes.

Here is a cannon which uses compression fittings:
[http://bb.1asphost.com/sigmarhaven/Ragnarok/DCP00932.jpg Behemoth]

Compression fitting

2007-01-27T12:02:07Z

LucyInTheSky:

Compression fittings are mainly used on copper pipe, they are very simle in the way they work. An olive, a small ring of bras not unlike in appearence to a wedding ring, fits over the copper pipe. Then when the fitting around it is tightened they will deform the olive so it grips the pipe.
Compression fittings are usually stronger than solder fittings by a small margin but are harder to airtight and dont look as nice.

Here is a cannon which uses compression fittings:
[http://bb.1asphost.com/sigmarhaven/Ragnarok/DCP00932.jpg Behemoth]

Main Page

2007-01-26T19:28:28Z

LucyInTheSky:

[[Image:Cannon.jpg|frame|An Advanced Combustion Cannon]]

=== The Spudding Handbook ===
Provided By The Users of [http://www.spudfiles.com SpudFiles]
----

[[What is a spudgun?]]

[[Combustion cannon]]s

[[Pneumatic cannon]]s

[[Hybrid cannon]]s

[[BB machine gun]]s

[[Cannon construction]]

[[Launcher configuration]]

[[Computer Applications]]

[[IPLA]]

[[Safety]]

[[Legal issues]]

[[History]]

This website is here to teach you about potato guns, also called spudguns, spudzookas, and spud chuckers. So far there are pneumatic, combustion, hybrid, and BB type cannons/launchers. Here you will learn all about spud safety, how to make things like breech loaders and what types of fuel to use in your spud gun (like propane, butane, hairspray, rightguard, etc.). You will learn the good and bad types of ammo to use as well as learn the best types of ignition (like stunguns, flint ignitors, BBQ ignitors, etc.) and how legal your cannon is. You just may learn how to get something totally free. You will learn about ABS and PVC pipe and how to correctly mount a pressure gauge into your cannon. You will learn all about the different kinds of valves and how to use them. (sprinkler valves, diaphragm valves, pistons, etc.) You will learn how to make a hybrid and a pneumatic/combustion cannon. You can even learn about strafers and submachine BB guns! Above all you will be able to find instructions on how to build things that you will love for years to come. All of this is totally free so be happy and get on to registering and posting!

-PCGUY (Kyle), maker of SpudFiles

==External links==

*[http://www.bcvids.com BCVids (aka Utopia), video tutorials (in part by PCGUY)]
*[http://www.bavetta.com/aircannon.html Air Cannon Barrel Length Numerical Analysis]
*[http://www.thehalls-in-bfe.com/GGDT Gas Gun Design Tool, simulation program for pneumatic guns]
*[http://www.spudfiles.com/Other/are_they_legal.php ATF Correspondence concerning spud guns]
*[http://www.spudfiles.com Spud Files (aka The Spud Cannon Database)]
*[http://www.spudtech.com Great source of spudgun information]
*[http://www.uksgc.co.uk/forums/ UK Spudgun Community The place for UK Spudgunning]

Breech loading

2007-01-26T19:26:45Z

LucyInTheSky:

'''Breech loading''' refers to loading the ammo from the rear of the barrel, that is, near the valve or chamber. It generally provides faster reload rates than [[muzzle loading]].

Many types of breech loaders are employed. These 3, which utilize un-modified commercially available parts, are described in rough order of their speed of operation:

One common method is to use male and female '''threaded [[adapter]]s''' to connect the [[barrel]] to the [[chamber]], as seen [http://www.spudfiles.com/forums/viewtopic.php?t=183 here] 
To operate, one has to turn the barrel several rotations at a significant amount of torque, especially if the threaded joint is under a load due to the weight of the barrel. The ammo is then inserted, and the barrel screwed back on.

As an improvement over NPT threaded adapters, one can use a '''[[union]]'''. 
Operation is similar to that of the NPT threaded adapter method described above, except that unions require fewer turns, don't require the entire barrel to be rotated, and don't require much torque except at the very end of tightening. The union in unscrewed, ammo is inserted, and the union is screwed back together.

As an improvement over even unions, one can use a '''[[Cam lever coupling|cam lock]]''' fitting to connect the barrel and chamber. A cannon with one can be seen [http://www.spudfiles.com/forums/viewtopic.php?t=311 here] 
To operate, one rotates the levers outwards, pulls the 2 fittings apart, inserts ammo, puts the fittings back together, and returns the levers to their original positions.

Valves that open by sliding open exist. These are typically put on one of the co-linear parts of a [[tee]]. 
The valve is simply opened, the projectile inserted, and the valve closed.

These methods which require more work to make (ranging from some work with a dremmle to installing O-rings) are described below:

One fairly common method is to simply hold the breach-end of the barrel into a socket (such as a [[coupler]]). Such a method is suitable for pneumatics, but the hot gases from a [[combustion launcher|combustion]] can cause erosion and discoloration of the material, unless an O-ring is used to make it completely air-tight. 
To operate, one undoes the latch mechanism holding the barrel, moves the barrel away from the coupler, inserts the ammo, moves the barrel back to the original position, and redoes the latch.
[http://www.spudfiles.com/forums/viewtopic.php?t=929& Example], [http://pneumaticsniper.mypicgallery.com/ Example]

In a manner that emulates the last stock-component method, one can make a plug to be inserted into the end of a [[tee]].
[http://www.spudfiles.com/forums/viewtopic.php?t=1637& example] 
To use, one removes the plug, inserts ammo, and replaces plug.

Another fairly common method of breach loading involves covering a hole in the barrel with a [[coupler]] that has had the inner stop removed, as in [[bushing modification]]. The same leak issues that exist with holding the breach-end of the barrel into a socket exist, and the solutions are the same.
Use entails sliding the coupler forwards, dropping the ammo in, and sliding the coupler back.

[[Category:Accessories]]

Breech loading

2007-01-26T19:26:15Z

LucyInTheSky:

'''Breech loading''' refers to loading the ammo from the rear of the barrel, that is, near the valve or chamber. It generally provides faster reload rates than [[muzzle loading]].

Many types of breech loaders are employed. These 3, which utilize un-modified commercially available parts, are described in rough order of their speed of operation:

One common method is to use male and female '''threaded [[adapter]]s''' to connect the [[barrel]] to the [[chamber]], as seen [http://www.spudfiles.com/forums/viewtopic.php?t=183 here] 
To operate, one has to turn the barrel several rotations at a significant amount of torque, especially if the threaded joint is under a load due to the weight of the barrel. The ammo is then inserted, and the barrel screwed back on.

As an improvement over NPT threaded adapters, one can use a '''[[union]]'''. 
Operation is similar to that of the NPT threaded adapter method described above, except that unions require fewer turns, don't require the entire barrel to be rotated, and don't require much torque except at the very end of tightening. The union in unscrewed, ammo is inserted, and the union is screwed back together.

As an improvement over even unions, one can use a '''[[Cam lever coupling|cam lock]]''' fitting to connect the barrel and chamber. A cannon with one can be seen [http://www.spudfiles.com/forums/viewtopic.php?t=311 here] 
To operate, one rotates the levers outwards, pulls the 2 fittings apart, inserts ammo, puts the fittings back together, and returns the levers to their original positions.

Valves that open by sliding open exist. These are typically put on one of the co-linear parts of a [[tee]]. 
The valve is simply opened, the projectile inserted, and the valve closed.

These methods which require more work to make (ranging from some work with a dremmle to installing O-rings) are described below:

One fairly common method is to simply hold the breach-end of the barrel into a socket (such as a [[coupler]]). Such a method is suitable for pneumatics, but the hot gases from a [[combustion launcher|combustion]] can cause erosion and discoloration of the material, unless an O-ring is used to make it completely air-tight. 
To operate, one undoes the latch mechanism holding the barrel, moves the barrel away from the coupler, inserts the ammo, moves the barrel back to the original position, and redoes the latch.
[http://www.spudfiles.com/forums/viewtopic.php?t=929& Example], [http://pneumaticsniper.mypicgallery.com/ Example], [http://i59.photobucket.com/albums/g294/PotatoesInTheSkyWithDiamonds_2006/PA280164-1.jpg/ Example], [http://i59.photobucket.com/albums/g294/PotatoesInTheSkyWithDiamonds_2006/PA280166.jpg/ Example]

In a manner that emulates the last stock-component method, one can make a plug to be inserted into the end of a [[tee]].
[http://www.spudfiles.com/forums/viewtopic.php?t=1637& example] 
To use, one removes the plug, inserts ammo, and replaces plug.

Another fairly common method of breach loading involves covering a hole in the barrel with a [[coupler]] that has had the inner stop removed, as in [[bushing modification]]. The same leak issues that exist with holding the breach-end of the barrel into a socket exist, and the solutions are the same.
Use entails sliding the coupler forwards, dropping the ammo in, and sliding the coupler back.

[[Category:Accessories]]

Linear

2007-01-26T19:18:56Z

LucyInTheSky:

A type of cannon where the barrel is directly in front of, and pointing in the same direction, as the chamber. It's slightly cheaper than the over/under configuration, but only by the cost of 2 90* elbows. The linear design is most often used in [[combustion launcher]]s, and this is considered the most basic launcher design. It's also the simplest to assemble, requiring no special tools or fittings.

The linier design is often considered slightly more powerful than over-under configuration as the traveling gasses dont have to make a 180* turn thus slowing the speed of them.

Most pneumatics are not Linear because of there increased chamber length and piston valve arangment.

Chamber

2007-01-26T19:08:46Z

LucyInTheSky:

The '''chamber''' or '''reservoir''' is the power source of a spudgun. It is, along with the [[barrel]], the only component found in all launchers.

In [[combustion cannon]]s, the chamber contains the flammable fuel/air mixture, offten butane or propane from an aerosol can of deoderant or from direct injection of the gas from a cylinder. If injected from a propane cylinder it is usually connected to a meter with regulates exactly 4.02% fuel into the chamber (the perfect amount).

In a [[pneumatic cannon]] the chamber contains compressed gas, usually air or CO2, however if the sound barrier wishes to be reached then a lighter gas must be chosen, offten helium or hydrogen (hydrongen is not advisable as it is extreamly flammable). The chamber is connected to the barrel either directly or through a valve, to propel the projectile when the energy is released.

The chamber is often the part of the launcher that is subjected to the highest stress, and it's important that it is well [[Cannon construction|constructed]] and offers a high enough pressure rating. It is also the part where the most accessories are connected, especially combustion launchers; they can have a multiple holes to accommodate [[spark gap]]s, [[chamber fan]]s, [[fuel meter]]s and for [[venting]].

[[Category:Components]]