SpudFiles

Hello friendly people of Spudfiles.com.

Im new to all this - this will be my first post. So excuse noob questions. I have had a look around first, to get some ideas, but havent found just what I need yet. Can I explain my plan, and you can all comment on the viability and offer up your thoughts if you are willing? Thanks.

I've been a paintballer for many years, and have made various paintball guns. Im not hopeless at hacking things together.

Im wondering wether I can make a paintball mine, that will fit inside a .556 ammo tin. This is smaller than most of your guns.



I would cut a hole in the side (or bottom ) about 100mm in diameter. Inside I would have a sprinkler valve, a pressure chamber with a gauge, and a paintball fill nipple, and the short wide barrel. This way anybody in the team could fill it from their remote line. Ideally an adjustable purge valve too, to make it safer.

I would use a PIR to detect motion to the front, and fire the solenoid that way. I'd add a safety switch, and allow a one or two minute delay after switching it on to allow the user to clear the area. I'd probably also add a remote firing system. I can do the electronics no problem....dont need help there.

The mine would fire a mass of paintballs poured loose into the wide bore barrel, like a shotgun. Velocity can be lower than you normally get with your spuds! Im aiming for an inaccurate short range shotgun effect.

What Im hoping you can advise about is this:

1) do you know of any examples of this already done?
2) will I be able to fit it all in that can? I hope so - as these need to be carried. Ideally, I'd make 10 so all team members carry one, and we place them around us in a defensive perimeter when we need to.
3) Would an air horn solenoid work instead of a sprinkler valve? (they're smaller, but also much smaller bore which is probably bad)

Thanks very much in advance for any helpful advice and suggestions.

pigeon wrote:Hello friendly people of Spudfiles.com

A brave assumption

I would cut a hole in the side (or bottom ) about 100mm in diameter. Inside I would have a sprinkler valve, a pressure chamber with a gauge, and a paintball fill nipple, and the short wide barrel. This way anybody in the team could fill it from their remote line. Ideally an adjustable purge valve too, to make it safer.

Sprinkler valves usually operate in the 150 psi range, while paintball bottles typically put out gas in the 850 psi range. You need to add a regulator to your system to bring the pressure down. Palmer Pursuit is your one stop shop: http://palmer-pursuit.com/cart/rock-reg ... kvkvudrtm7

I would use a PIR to detect motion to the front, and fire the solenoid that way. I'd add a safety switch, and allow a one or two minute delay after switching it on to allow the user to clear the area. I'd probably also add a remote firing system. I can do the electronics no problem....dont need help there.

Throw in an arduino and the possibilities are endless

The mine would fire a mass of paintballs poured loose into the wide bore barrel, like a shotgun. Velocity can be lower than you normally get with your spuds! Im aiming for an inaccurate short range shotgun effect.

I don't think you would get a wide enough spread. Multiple barrels are probably a better idea.

This airsoft mine is a good example to look at:

1) do you know of any examples of this already done?

Not as sophisticated certainly.

2) will I be able to fit it all in that can? I hope so - as these need to be carried. Ideally, I'd make 10 so all team members carry one, and we place them around us in a defensive perimeter when we need to.

You should probably be looking at .50 BMG cartridge boxes, a sprinkler valve large enough for your purposes is a pretty wide thing.

3) Would an air horn solenoid work instead of a sprinkler valve? (they're smaller, but also much smaller bore which is probably bad)

Not only is the bore far too small for your purposes, but air horn solenoids tend to "fart" air out at a rapid pulse rate as opposed to blowing it out unobstructed like a sprinkler valve.

Although not quite the same as what you had in mind, either of these designs could be modified very easily for your purposes,

http://www.instructables.com/id/Build-a-Paintball-Mine/

http://www.instructables.com/id/Trip-Wire-Paint-Mine/

As a general thing, I think firing paint is probably going to be easier than simultaneously firing paintballs, along with probably ending up cheaper.

Thank you both for your thoughts. I do have a palmers reg somewhere - its not currently in use. Would prefer to keep it cheap as I want to make many. Was hoping that when the remote line is connected to the mine, you could carefully screw in the pin valve, and watch the pressure gauge on the mine. Bad idea? I was also thinking a purge valve that kept the pressure at 100psi for example, would be the safety? I havent seen any examples of that though - probably for a good reason.

arduino - yup - made quite a few things with those already and am considering the options here. Like networking the mines, and having a remote control (wireless) switching panel This could also allow them to be armed and disarmed from a safe distance (behind!) when they're all in place.

The rainbird solenoid valve I have does fit quite easily in a .556 box. Just takes up quite a bit of the total volume though.

good to know airhorn solenoids are no use.....I'll abandon that.

cammyd - seen those before. Kinda prefer to shoot balls at people than liquid - a bit more realistic, and more painful. Cost of ammo not a problem - we always have a lot of ammo! I could do the multiple barrels idea though - .68 cal, or .43 cal (we run a lot of .43 cal guns in the club).

So, it just so happens that I am building this nearly exact thing right now. I have solved MOST of the problems of cost, filling, etc.

I will attach a couple pics of the working prototype. It is a fishing line trip-wire activated Claymore type horizontal firing mine that is filled with one single 12gram CO2 for each shot.

Right now, I am using a paintball 12gram adapter attached to the mine to fill it. The air chamber is designed from 2" PVC schedule 40 that has an operating pressure of 280 PSI. It is designed with a chamber volume calculated to pressurize to about 270 PSI when filled with a single 12 gram cartridge. This is much easier and cheaper for this application than trying to downregulate CO2 tanks or HPA to a defined pressure. The Spinkler valve I am using seems to tolerate that well and it is the Orbit 1" Jar top modified via the nice guide here: http://thehalls-in-bfe.com/GGDT/library ... 1_mod.html

I am going to remove the 12 gram adapter and replace it a Shraeder valve so that I can just fill it using a 12 gram CO2 bike tire inflater like this one:

Advantages of the claymore type over the vertical firing mine is the ability to use a trip-wire, no need to bury it, and the much greater likelihood of hitting one or more opponents.

It currently works great with liquid paint spray, but I am going to test it out with paintballs soon, which should increase the effective range.

Humancarpentry wrote:So, it just so happens that I am building this nearly exact thing right now. I have solved MOST of the problems of cost, filling, etc.

Looking good! Personally I would have gone for a smaller chamber at higher pressure in the interest of compactness, and used a ball valve as a pilot since it is much more easily activated by tripwire. Using the original solenoid piloting would have allowed for all manner of electronic triggering options, albeit with reduced performance.

humancarpentry - thanks so much sharing. You're doing exactly what I plan to do. Good to see the 12gram option.....being a spudgun noob, but a paintballer - I didnt think of this but can see how obvious it is now! You're considering changing to use a tyre filler with the 12 gram? Why's that? More or less the same outcome right?

I think Im going to just go with what you've done. But try to get it to fit in the .556 ammo tin, and add the electronics options with a PIR and probably a micro Arduino of some sort. These Trinket's are just 8 bucks, and I dont suppose I'll need more IO than 3/5.
http://www.adafruit.com/products/1501

This is so helpful - thanks!

Thank you humancarpentry! So helpful - Im going to go with that basic design. I might do the shraeder valve too, as it'll be cheaper if I make several. Only needing one 12g co2 "dispenser".

I'll keep the solenoid though, so I can trigger electronically. I'll do it with an arduino - maybe a "trinket" - they're only $8.....limited GPIO but it should be enough.


http://www.adafruit.com/products/1501

looking at what you've done - I can probably fit that in the ammo box.

p.s. Have you considered the 8gram CO2s you get for soda siphon's - much much cheaper.

That Orbit Watermaster valve is rated to 80psi. You're running it at 270. Can I assume then, than I dont need to worry too much about the pressure ratings on these things? Most of the ones I can find available here in NZ are rated to about 150psi.

Well, in regards to the valve rating, I slowly increased the pressure on it over time while testing it under a thick blanket in case anything were to explode. Hasn't even leaked yet. I think it can probably take more than 270 psi despite the rating, but others on this board would probably have more experience with that. I would not assume safety with anything off the bat. Jack's idea of a higher pressure metal chamber and I am assuming a metal QEV is a good one, probably safer, but likely more expensive.

Jack - the triggering mechanism is not quite finished. I will actually use the airgun as in the pic, but I am adding a heavy rubber band and that will squeeze the trigger when the tripwire pulls out an interposed spacer between the trigger and blowgun handle body. This should make triggering rapid for good valve performance yet still easy to do with the fishing line tripwire. The solenoid would allow for electronic triggering with worse valve performance, but during a paintball game I don't have time to mess with anything complicated or requiring a power source and batteries. Also, with motion detection, there is a major issue with even light wind moving leaves and bushes and causing triggering of the motion sensor.

I also would like to go with a high pressure small chamber, but then I couldn't use the nice $10 Orbit Jar top valve. I'd have to get a QEV or something which I am not experienced in using and would probably cost more $$$.

I am switching to a Schraeder valve and 12 gram CO2 tire filler for ease of filling on the field without extra tools. It allows me to carry one filler, multiple 12 grams and doesn't require me to screw anything on or off the mine. Can be placed and filled in under 30 seconds. Also, I am shortening the dark gray 1" PVC nipple that connects the air chamber to the valve for compactness, and adding a ground stake for stability.

Sorry, missed the PS. The 12grams I buy on Amazon are already pretty cheap. I don't think 8 grams of CO2 would be sufficient for accelerating my paintballs to sufficient speed to break on an unlucky opponent.

The QEVs - whats the score with those? These are smaller, and also electrically operated sometimes right? Could I use one of those in the interest of compactness? What are the pros and cons?

Here in NZ, there are only a couple of brands of sprinkler valve - not much competition - and they're all expensive. There are no $10 ones. $35 the cheapest I have found, excluding tax.

pigeon wrote:The QEVs - whats the score with those? These are smaller, and also electrically operated sometimes right? Could I use one of those in the interest of compactness? What are the pros and cons?

A QEV is pretty much the same principle as a sprinkler valve but they tend to be more compact and you have to supply your own pilot valve. All in all a sprinkler valve should work out cheaper. The downside is the limited pressure their plastic body can take.

That Orbit Watermaster valve is rated to 80psi. You're running it at 270. Can I assume then, than I dont need to worry too much about the pressure ratings on these things? Most of the ones I can find available here in NZ are rated to about 150psi.

The working pressure is usually well below the pressure that would cause catastrophic valve failure, there is usually a safety factor of at least 1.5. Not recommended to exceed the manufacturer's specifications of course, but a 150 psi rated valve will not explode at 151 psi.

Was hoping that when the remote line is connected to the mine, you could carefully screw in the pin valve, and watch the pressure gauge on the mine. Bad idea? I was also thinking a purge valve that kept the pressure at 100psi for example, would be the safety? I havent seen any examples of that though - probably for a good reason.

Do not attempt this unless you include one of these in your setup.



It is too easy to cause a overpressure.

Here is something interesting, not along the lines of your requirements, but at any rate interesting.

[youtube][/youtube]

thanks Jacks - I see that you can get those in lots of different ratings, so if I go with the remote line filling option, I could try different ones to get the optimum velocity. Start low, and go up in stages. If I used one of these on each one, I guess they could be filled until the valve releases some pressure - then they're full. This would mean I wouldnt need a pressure gauge on each one, and they'd always have the same pressure.

Or perhaps I'd need the gauge too, so Im not relying on the relief valve entirely.

Or I could go with the 12gram bike tyre filler and schraeder valves - another simple option, but I wouldnt be able to adjust the pressure...I'd have to hope that humancarpentry's design worked, and I suppose change the barrel bore and length to adjust the load, to get the right effect.

pigeon wrote:If I used one of these on each one, I guess they could be filled until the valve releases some pressure - then they're full. This would mean I wouldnt need a pressure gauge on each one, and they'd always have the same pressure.

Yes and no... if for some reason the safety valve fails to vent, you've just made yourself a nice little PVC grenade.

Or perhaps I'd need the gauge too, so Im not relying on the relief valve entirely.

If safety is a concern, ideally the bottle being used to fill the devices has a palmer reg on it set at say 150 psi, that and a safety valve on each mine should work well enough.

CS wrote:Mr. Plow's video

Hmmm... I wonder what a more hardcore version would look like...