SpudFiles

I'm starting to get back into r/c planes and away from spudguns because my parents don't really like me building them. But with that comes the ever increasing need to make one. Only it isn't for shooting marbles out of sight, piercing the shed with darts, or sending up a cloud of bb's in the general direction of my neighbor's BBQ.

Now I need to fetch my planes when the wind takes them and they stuck in trees and up on roof tops. I got one of my planes stuck on the roof today. My first idea was to shoot something up toward it with a string tied to the end. But without a specialized gun though, it was nearly impossible so I resorted to using poles and other contraptions.

But, with my knowledge of spudguns, I'm setting out to build a pneumatic cannon that will help me retrieve my planes with ease.

My first design is similar to the Antenna Launcher. I plane to start with a basic over/under using either a sprinkler valve or a QEV and a "spool" consisting of a 45* with plenty string wrapped around it. If that doesn't work, I'll rig a fishing reel to it. The barrel will be 2" to fire a Micro Nerf Vortex with a string attached.



Ideally though, I want to build a compact coaxial. 4" chamber with 2" Barrel. Does anyone know of a way to make a coaxial that size without having to use a 3" cap? A piston that size would make the launcher bulky.

Ideas? Suggestions?

That looks cool! Nice picture. I don't know R/C planes well, but I'd be a bit concerned about the nerf blowing up the plane like a sidewinder missile. Even if it is foam, that could seriously harm your plane. And from watching Lost I wouldn't trust the airplane to survive.

Sounds pretty good to me, but I also agree that I would imagine that would hurt your plane, even if you shot the nerf ball at a minimum PSI to get it up there. (I'm into R/C planes too)

One thing I must say is if the string around the pipe doesnt work and you do use a fishing reel, your going to haveta watch out that the spool doesnt "birdnest" because of the fast drawout of line and tangle up into one big ball of mess on you.

Good luck though! And it does seem like an interesting gun to see

i like the idea but just be careful. r/c planes can be expensive and damaging one could be dangerous.

Not at, near. All it takes is for the string to snag it.

You could make a diapragm coaxial, but I dont see how a 3" cap would make it bulky. It would be the same size as any other piston...

Even though you're not aiming at the gun, I'd still stick with a latter. Maybe you can rig up little rocket engines on your plane, and if it does get stuck somewhere, you can blast it out using rocket thrust! Just joking, but if I were you, I'd tie a string to the plane, or add weight to the plane and soup up the motor to make it heavier. But then again, I have no knowlage about R/C planes...

Stick the 3" cap in there so that the 2" is sealing on the inside of the cap.

clide wrote:Stick the 3" cap in there so that the 2" is sealing on the inside of the cap.

Genius.

How much travel should a piston that size have?

For a 2" barrel you need .5" of travel. 1/4 of the barrel diameter for coaxials.