Ok I recently made a spud gun.just a casual one it has a 3" chamber and 2 inch barrel the barrel is about 3 ft long maybe a little longer. 4 ft max and the chamber is like 2 ft long with a 3in to 2 in adapter I'm using a regular grill igniter for my ignition system. I'm having 3 problems .
1. I get a lot of misfires , I use hairspray for a propellant
I'm not sure what the problem is. Any suggestions on what a Better fuel would be . Should I make a propane meter and use propane?
2. On a lot of my air cannons I get leaks I'm not sure why because I always use job weld or Teflon tape. But on this spud gun I jb welded the igniter in and sometimes it leaks out hot air from the job weld how can I fix this? Just add more?
3.the cannon isn't very powerful it doesn't shoot very hard , I was shooting a piece of PVC pipe wrapped in electrical tape with the front sealed and it shot like 35 ft and it wouldent do any damage
What should I do to fix these problems? How can I make the cannon better? Thanks in advance.
Spud gun. Help me please
sounds like u use too much hairspray.
what brand u should use depends a little on where u live in the world. and what u have avaiable.
a meetered system will always give u more accurate and controlled explotion.(read more powefull)
there is a few treads here talking about different spray and pray propellants
what brand u should use depends a little on where u live in the world. and what u have avaiable.
a meetered system will always give u more accurate and controlled explotion.(read more powefull)
there is a few treads here talking about different spray and pray propellants
To make dreams come true, u must wake up.
To make dreams come true, u must wake up.
If you're using "Hairspray" and getting results,
Probably that brand uses propane for the "propellant" gas.
The rest is sticky residue that just makes a mess.
A "spray and pray" is always just that...You spray some (propellant or gasoline drops) in and "pray" it will fire.
SO YES, use propane and a metering pipe.
I've found it easiest to use "Metric" measurement, and calculate about 5% volume of propane GAS at atmospheric pressure.
For small chambers: I go to CVS or whatever pharmacy and ask for a "Baby oral syringe" I don't use it for the meter pipe, just for determining meter volume/chamber volume (using water usually).
To get propane in gas volume, I need the tiny pin-hole propane torch tips.
There used to be a link (store on here) that sold smaller one's but I don't see it (or know where to get one???).
Be carefull because in a lot of states, Anything which uses an "explosion" to project the [whatever] iS considered a "Firearm" depite Federal Law.
Good luck! 8)
Probably that brand uses propane for the "propellant" gas.
The rest is sticky residue that just makes a mess.
A "spray and pray" is always just that...You spray some (propellant or gasoline drops) in and "pray" it will fire.
SO YES, use propane and a metering pipe.
I've found it easiest to use "Metric" measurement, and calculate about 5% volume of propane GAS at atmospheric pressure.
For small chambers: I go to CVS or whatever pharmacy and ask for a "Baby oral syringe" I don't use it for the meter pipe, just for determining meter volume/chamber volume (using water usually).
To get propane in gas volume, I need the tiny pin-hole propane torch tips.
There used to be a link (store on here) that sold smaller one's but I don't see it (or know where to get one???).
Be carefull because in a lot of states, Anything which uses an "explosion" to project the [whatever] iS considered a "Firearm" depite Federal Law.
Good luck! 8)
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jimmy101
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4% (by volume) for propane in air at 1X. (Not 5%)
Search the spud wiki for "syringe" and start with a syringe based meter. It'll cost a tiny fraction of what a pipe based meter costs. (A syringe meter can be done for less than $5, including the fuel source.)
Next thing is a chamber fan. You can get about the same performance without the fan but you need to wait two or three minutes after fueling to let the gases fully mix.
A syringe plus patience will get basically 100% of the possible performance out of the gun. A dedicated meter, fan etc. make the gun slicker but won't improve performance.
You shouldn't have epoxied the sparker into the chamber. Use a pair of fine thread deck screws as the electrodes and connect them to the sparker with wire. (Deck screws have sharp points.) The screws won't leak.
I sure hope you used the proper glue. If the gun is PVC it should have been assembled with PVC and nothing else.
Search the spud wiki for "syringe" and start with a syringe based meter. It'll cost a tiny fraction of what a pipe based meter costs. (A syringe meter can be done for less than $5, including the fuel source.)
Next thing is a chamber fan. You can get about the same performance without the fan but you need to wait two or three minutes after fueling to let the gases fully mix.
A syringe plus patience will get basically 100% of the possible performance out of the gun. A dedicated meter, fan etc. make the gun slicker but won't improve performance.
You shouldn't have epoxied the sparker into the chamber. Use a pair of fine thread deck screws as the electrodes and connect them to the sparker with wire. (Deck screws have sharp points.) The screws won't leak.
I sure hope you used the proper glue. If the gun is PVC it should have been assembled with PVC and nothing else.
