Forget amateurish sprinkler valves. Look no further than this type of valve for making airguns or anything where you need the air released explosively. This is my own design inspired by the valve inside an airbrush.

This instructable shows you how to make what I call the XRV (explosive release valve), which can be attached to a bicycle pump. This in turn allows you to turn an ordinary blowgun or pea-shooter into something a bit more serious.

The video does a lot of explaining, but for more detail including how it works, see the next steps.

Step 1: Materials and Tools

To make the XRV, you need a handful of easy-to-find components:


1. Flexible bike pump hose - comes with most bicycle pumps)
2. Brass or aluminium tubing (about 1-2mm) - available from hobby stores
3. O-Rings (tiny) - available from hardware stores
4. Small spring - also from hardware stores
5. Tiny screw that fits into the end of the 1-2mm tubing
6. Tiny nut or washer that fits onto the brass tubing (see video)


1. Hand drill & very small drill bit
2. Fine file
3. Blade
4. Precision screwdriver
5. Pliers or multi-grips (pictured)
6. Hand clamp
7. Superglue
I used your design and upped the sizing a little for a little more oomph. And instead of using superglue I used solder for added strength.<br>Awesome design on your behalf, works an absolute treat!! Keep up the good work!
fantastic work! I'd love to see your finished valve in action when you're done. I'm in the process of upsizing mine too :)
http://i44.tinypic.com/w2na1k.jpg <br> <br>The completed project. 5/32 tubing, JAMEC style quick release male connector with a 5/32 hole in the middle and suitably sized everything else. For the people who want a little more top end in their project. Good for 4mm BBs
i tested it using my compressor and needless to say the compressor could not create enough pressure to make the valve fail, got it to 250psi and hoping it will go to at least 600psi haha
haha wow. At what pressure does it become too difficult to pull the valve in? I started designing a trigger system that uses a tubular hammer to hit the valve and release the air but never got around to building it. With something like that, you'd be able to get multiple shots from a single tank.
<p>Im making some thing like this an you helped me in the good derection. A shame you never finished it. Im hoping i can make just like you inof time to finish mine. </p>
Did you ever get to making that trigger system I'm currently trying to figure out how to make one that will have an outer valve over the exhaust that when I pull the trigger pushes forward the outer valve closing off the magazine (I'm making a semi auto airsoft air gun) so that air pressure isn't lost into the magazine and also pulls the valve back to release the pressure
<p>instead of just a nut try a wing nut :!</p>
<p>clever idea</p>
<p>If the author does not reply to this, I assume he got arrested.</p>
<p>yes. I'm replying from jail.</p>
<p>Hello chluaid,<br>Thanks a lot for your tutorial, very good mechanism. I tried to make one and integrate it inside a Nerf N-Strike Relfex, here is the description : <a href="https://www.instructables.com/id/Nerf-N-strike-Reflex-mod-with-XRV-valve/" rel="nofollow">https://www.instructables.com/id/Nerf-N-strike-Refl...</a></p><p>The testing has yet to be done.</p>
<p>hey man, nice job. Looks great!</p>
<p>Hurry up and buy this:</p><p>QUICK EXHAUST VALVE</p>
I slightly messed up by screwing an ever-so-slightly larger nut into the end. I mean, it will still lock in but the clearance between the housing I'm using and the tube is already very slight. On the plus side it doesn't need super glue, but it will mean it needs some wet/dry on the outside to fix the clearance or a simple trigger to push it back into it's spot after firing.
Go to any good hobby store and they will have the small tubes. Brass, copper, aluminium. 1, 2, 3, 4, 5, 6, 7mm brass, equal for the others. 305mm lengths, but they sell imperial sizes(1/16th, 1/8th, etc). Depends what you want I guess. If you want to experiment with the same size, just buy a 1m/36&quot; length of the tube and have at it. <br> <br>I ended up with 5mm(4.97~4.99mm) because darts like the extra air, however the connections to the air supply will be the hard bit. I managed to find a strong spring and the right sized screw in my box of bits, so now making a housing will be tricky. If you order something, make sure it is slightly small than required and either use a small file to make it bigger by the require amount, use some wet/dry on the shaft, or use some valve lapping compound and slide the two bits together to make the fit perfect. The better the fit, the less air escapes, and the more pressure you can put into the tube to shoot whatever you're shooting out the end. <br> <br>420 O-rings on ebay of various sizes for $15.50 <br> <br>Anyway my thoughts on making this for a semi-auto; <br> <br>1. Use thick walled tubing, you'll want to run a large amount of pressure behind the valve(3-400psi perhaps) <br>2. Use a strong spring. Remember, a trigger provides some mechanical advantage, so if you can barely compress the spring because of it's stiffness, then just modify the trigger to suit. <br>3. You need a way for the valve to release when the trigger is pulled and return whilst the trigger is still depressed, so you don't drain the reservoir or fill the barrel with BB's <br> <br>Everything else will be simple enough. A paintball tank for the air, the valves/regulators will be the same as from the paintball gun, but the gun itself is expensive to import to countries like Aus(permits, fees, licences, blah blah). <br> <br>Of course for a single shot this isn't a problem, just remember to take your finger off the trigger. Also be careful with paintball tanks, some are good for 5000PSI(average 3000psi), so you'll definitely need a regulator to get the right amount of pressure. Otherwise, a copper tube with ends brazed on and a schrader valve(like from a bike tyre) will probably work for a few shots so you don't have to keep pumping. <br> <br>Just some thoughts
Some extra information; <br> <br>I've been looking at making a slightly larger one using off the shelf parts. Anyway, I found a quick release connector(the male bit). It has threads on the inside, with a 5/32 hole in the middle. You can easily get 5/32 brass tubing, and it is a nice size to work with due to the weaknesses of tiny drill bits(plus the tollerances are tight,. The upside of using premade connectors like this is that there is usually a barb fitting with the opposite threads and it all screws together(just get some teflon tape). 10mm hose connected to a tank to hold some pressure and you're in business. <br> <br>4-500psi may be safe through this depending on the wall thickness of the tubing used, the seal in the fitting and the tube, the tube construction(extruded or drawn), etc
For y'all who be wondering where this guy got the little tubes, wonder no more! <br>http://www.amazon.com/gp/product/B000BRHE4M?ie=UTF8&amp;force-full-site=1&amp;ref_=aw_bottom_links <br>A <br>Took me forever to find. Enjoy!
What about water? How would this do shooting a stream of water?
i machined a much larger version of this for my air rifle would anyone like to see a slideshow or ible??? credit to chluaid <br> of course
I'd like to see it myself I'm at <br>p a ll a d i n 9 8 0 0 0 at g m a i l period c o m <br>I'm an old dude living in Mexico building slingshots and crossbows a la J sprave for fun and profit
I would love to see what you have<br><br>huguesb.1968@gmail.com
yeh a slideshow would be nice. <br>
PLZ RESPOND can a larger version be created with this design obviously stronger materials though. and i was wondering if instead of a bike pumb could i use a co2 cartridge. the cartridge wont be hook up directly to your device but will instead be put on a reservoir with a shut of valve and all that good stuff. btw never made a air gun but know how and what to make a gun the shoots 5 canadian quarters attached together. hopefully somewhere around 700+fps. something that will put a hole through a wall and another wall and so on. by the way AWESOME DESIGN
could i modify this gun to be automatic http://www.amazon.com/Crosman-1377C-PC77-Black-pistol/dp/B006QVTBVG/ref=pd_sim_hi_85 to shoot darts
I have been looking for this video for years. im making an automatic bb gun (pistol) and this is perfect for the trigger. thanks a lot man!
if you make the automatic bb gun please post it on instructables because i have been also trying to make one...the hard part is making it automatic
Got to start by saying thank you for this instructable the best I've seen so far.<br><br>I haven't settles on what I will build yet, BBMG or single shoot, but one thing is for sure I will be using your valve ins some fashion.<br><br>for you gents that are looking for an automatic simple design I found the following a while back and it seems to be a nice fit for this valve.<br><br>automatic BB gun<br>http://www.swanstrom.net/petes/shoot/autobb.htm<br><br>Have fun and stay safe...!<br>
how big of a pellet can this shoot?
where did u get the hand drill?<br>i really,really,really, REALLY WANT ONE!!!
This is a wonderful design and your video was awesome as well! Good job!
i want all the tubes in step 3..... <br>where did you get them?
finaly!! i found somone who actualy knows what hes doing,.'<br>Grate woork!<br>i made a simulare gun som years back:) i have made very many air guns, and the valve you made is very good :):)<br>see my channel i if you are intrested in a springpowerd airpistion gun.<br>keep up the good woork!
hey im planning to make this but dont have the bike tube for it. could i use a ball inflation needle to do the same thing as it. i lost my old bike tub and hope this will work
why dont you just go out and buy the tube then there probly no more then 5 bucks?
i didnt know where to find them. but i got it. I made one well not really. I made one that is a trigger for my spudgun, it's the pilot on my sprinkler valve.it about 5 in long and never leaks air. It has a huge airflow too. I will post a pic of it and how to build it if you want me to
ahahahahaha i found my old tube. it was in my air compressor parts box. i looked in there hundreds of times and it was right in front of me. hahahhaha im so happy :)
one last thing. i made this and it worked great. i am going to try to make a larger scale one for a trigger on my sprinkler valve in my spud gun. any ideas on what materials i would need to make a larger scale one. oh and would a large scale one hold around 60-70 psi maybe 80
Happy late christmas. http://nerfhaven.com/forums/index.php?showtopic=19073
Rather than going through the hassle of hand-drilling, you could just use the small round hand file to make the holes. If you file perpendicular to the pipe, it'll make a good path for the air to escape.
Do you have any idea how much pressure you think this little valve can take? I'm thinking of making a gobstopper gun that I can kill squirrels with and I'd like to maximize my energy output. I'm thinking of using a compressed air or CO2 tank as a power source and a regulator to tone down the pressure that's behind the valve.
i'm going to make one of these tomorrow and im using a piece of pipe from a telescopic antenna :P, they come in loads of different sizes
ya antenna works great. just take out each pipe form it and u have lots of choices. it is a can bend and is a little flimsy though :(
great vid! lol, how long did it take you to come up with the valve? oh and how many pumps would it take to propel a bb over say, 75 foot?
Excellent animation in the video - also great valve design.
Cool vid - you should go to the film industry ! :)
Can the hose(on the pumping stick) take on the pressurized air with-out getting it explode?
nice vid
no chance youd make my life easy and sell me one would u ?
Suspension pumps are not cheap! Would an tire pump suffice?

About This Instructable




Bio: I make stuff!
More by chluaid:Chluaid's 10-minute Monkey Fist Airgun with eXplosive air-Release Valve Piano-wire Slingshot 
Add instructable to: