SpudFiles

Ever since I saw the "Trident" launcher I've been thinking of designing a multi chambered/ multiple shot cannon using 1,2 or 3 liter bottles as chambers:




-------------------------------------------------
GB Barrel 1.5" o---o---o---o---o---o (GB's lined up in barrel)
--------------------------T---T---T---T---T---T
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,:)
Several 1" Sprinkler valves (hooked up for elec.)
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,(_)-(_)--(_)-(_)-(_)-(_)
A 1 or 2 liter bottle for each valve.


I was thinking of a design for pnuematic that is similar to a "firestorm"--EDIT: Ooops, It's "Metalstorm" (link at bottom)
Or roman candle concept.

It would have say a GB barrel with T fittings with a 1" sprinkler valve going into the bottom of each T and 1or2 liter bottle going into each valve.

The GB's would have a plastic or wooden rod attached, to seperate each shot to keep them in the right position above each valve(in same barrel).

If it's fired electrically the first trigger impulse would fire the first shot and then the one behind until each chamber is empty from the front back.

I have two questions about the design.
One is after the first chamber empties by opening the valve, when the second fires, will the air enter the empty chamber through the valve

A little leakage into the empty chamber through the valve in front may still work ok but I don't know how much will be lost if any.

Other question is how can I wire the push button switch to fire the first valve on first push second on second and so on

Thanks I could post a better real drawing since this one's so crappy but I wanted to know what you all think. Thanks in advance. 8)

EDIT: I was confused about the name, it's "Metalstorm" not "Firestorm" Like:http://www.youtube.com/watch?v=8DRmuljq ... re=related 8)

Thats going to be really expensive... Make one valve, but alot of chambers. Between a chamber and sprinkler valve, there is a ball valve.

So you start with 1 BV open, and the rest closed. Then trigger the SV (sprinkler valve). CLose the first BV, open the second one, and fire and so on.

Yeah i know that kinda ruins the concept but this comment is a concept in itself.

why not just make several guns and fire them off individually? thats what this sounds like, the only common piece , unless your crude graphic is what i have wrong, and i think what i interpret from your diagram is that when you fire the first, the second will be drawn forward by a slight vacuum created as the first leaves the barrel, possibly not two far as to not fire. about your electronic actuation find a dial with several settings, should be fairly simple to wire, ill make a diagram and edit this post with it... i feel this idea and i think i like it...

EDIT: okay here is a simple diagram for the setup, but you do have to readjust the dial between each shot, but its a way to do it, pretty simple too... you can probably find the switch at radio shack, of possibly home depot
the blue represents the dial, red is positive and green is negative, be sure your selection is off the positive side, that way any resistance from the switches is after the actuation point in the circuit (current path flows negative to positive...)

Hydra wrote:Thats going to be really expensive... Make one valve, but alot of chambers. Between a chamber and sprinkler valve, there is a ball valve.

So you start with 1 BV open, and the rest closed. Then trigger the SV (sprinkler valve). CLose the first BV, open the second one, and fire and so on.

Yeah i know that kinda ruins the concept but this comment is a concept in itself.

Exactly, that was my first idea, to use plastic ball valves and open and close each like that.

The problem is that as each BV is opened the distance of the pipe they're going into (before the valve) becomes longer and the pressure will drop for each one cosiderably.

Also if only one valve is used it would need to be loaded manually somehow as well.

I think if this design will work it would be worth the extra valves and I was even considering having two barrels loaded like the picture.
Well if I had more than one valve right now I'd test it on a two valve model and find out.

The real advantage to plastic bottles is with weight savings. Also a 2 or even 1 liter is an ok volume for GB's. Thanks

Way too complicated for me when i'm sober

@daxspudder, thanks for the diagram. I like that because it would be semi-auto by moving the switch slow or full-auto by moving it quickly.
I still would prefer a single push button that on one push closes one switch second push closes another and so on.
I was going to ask at radio shack but it seems like there aren't any real electronics guys in there any more. They must've gotten better jobs or something.

With the concept I was thinking of drilling a hole at the back of each GB and glueing in a dowel rod then drilling a hole in the front to put the dowel of the other GB into.

The length of this dowel will be just right length to position each golf ball just in front of the hole in a T fitting.
On the bottom of each T is a sprinkler valve and on each sprinkler valve will be a plastic bottle.

So it's like several guns but they're sharing a barrel.
As the GB's are fired they would skip over the opening in front that fired each shot before. It's not a vacuum feed or anything.

That's why I am wondering how much of the propelling air will enter the valve/chamber of the spent chamber(s)

@BigGrib It's really not very comlicated, the" firestorm" designs for firearms as seen on futureweapons or youtube of it are much more simple than other firearm designs because there's practicaly no moving parts.
BTW it's interesting that in roman candles the first shot has the most propellant because the barrel tube is shortest then each other ball has progressively less. This concept would be useful in a pneumatics design similar to maintain consistency as well.

further back on the gun use larger bottles, like 1l,1l,2l,2l,3l,3l plan on having your T fitting being "upside down" that way there is no drag on the GBs and i dont think the other chambers will effect your pressure, they might silence it a little after the first shot and progressively more with each successive shot... and about your thought of push push push switching between chambers is possible, give me some time to crunch the idea and ill have no issue giving you a new diagram with less manipulation to fire required design... if you have looked at my profile, you'd know im a fire control technician for the navy, and fire is as in gun, not matches...

EDIT: again a new diagram for you, this idea works like a semi auto, the diagram lacks a spring which is necessary and there would need to be a way to send the switch forward again
each pull of the trigger moves the switch one step farther back actuating another valve with each pull, could be set up between two flat pieces mounted inside a piece of pipe maybe, it would hide the whole setup and averything you need for it can be home manufactured with a dremel...

What if you had the sprinkler valves piloted in series? Say you have your first valve piloted by a blowgun, ball valve, etc, then run a hose from the pressure side of that sprinkler vavle (have a hole in the body of the vavle) to the top of your next vavle.

When the first valve fires, the pressure drop in the chamber side pilots the next valve and so on.

A problem I see is that there wouldn't be much selection of "firing modes" (auto, semi, etc).

Also not sure about the delay between each shot, the rof may decrease as you go down the line of vavles...

Just something to think about

I've seen a circuit that does what you were describing. Unfortunately the circuit diagram has since disappeared from the internet, but I did find out that it was made with a 4017 chip that has a nice little animation here http://saint.419.removed.us/counter.html

I believe your firing switch would be hooked up to the clock and you would need a debounce circuit as mentioned on that page. I have no idea what that is, but I'm sure Google would lead to an answer.

And yes air would have a tendency to go into the previously used chambers. You could use a check valve after each sprinkler to prevent that.

@ clide Thanks for the link/ information, I will check that out better, but it looks like the circuit I am thinking of.
I know it can be built fairly easily and compact because it was a project in a micro-computer repair class I took years ago.
We put curcuits together for a project on "and/or/not" diode anode and cathodes (can't remember) it was just a counter to light up led lights in different orders.
Thanks for the idea about the check valve(or similar design).
That is exactly the cure for air entering the spent chamber(s) and one could be added between each valve and the T it fits onto.

I will post a better drawing soon hopefully but I have kind of a lot of stuff going on right now.
Also, Thanks daxspudder and biggsauce for your great replies

BTW It seemed like an idea bcarms would enjoy, between the Gb barrel and use of several valves. 8)