Search found 12 matches

by MCRKilljoy
Thu Jan 05, 2017 8:52 pm
Forum: Ammo & Parts
Topic: 2.5" PVC to 2" threaded male adapter - more elegan
Replies: 11
Views: 2131

Re: 2.5" PVC to 2" threaded male adapter - more elegan

Maybe I am lucky, but my local hardware store sells 2.5" pipe and all sorts of fittings! But I don't need them because I have a steel pipe QEV gun.
by MCRKilljoy
Wed Jan 04, 2017 10:29 am
Forum: Pneumatic Cannons
Topic: Iron pipe?
Replies: 12
Views: 2078

Re: Iron pipe?

That pipe is "Black Iron". It is rated to 150 PSI for steam. The rating for compressed air with threaded joints 500 PSI. Welded joints will have a much higher pressure rating, While the name is black iron, the pipe is actually steel and very strong. The only pipe that is actually made of iron is cas...
by MCRKilljoy
Sun Jan 01, 2017 12:59 pm
Forum: Pneumatic Cannons
Topic: High Pressure QEV Air Gun
Replies: 4
Views: 2188

Re: High Pressure QEV Air Gun

foot/pounds are a measure of torque, not velocity. Are you sure you don't mean feet per second? A quick calculation assuming around 20g for an AA battery gives around 3⅓ Joules. Or maybe you meant foot pound *force*, which is a measure of energy and not velocity, in which case that's around 81 joul...
by MCRKilljoy
Sun Jan 01, 2017 12:43 am
Forum: Pneumatic Cannons
Topic: High Pressure QEV Air Gun
Replies: 4
Views: 2188

High Pressure QEV Air Gun

I improved my air gun! I made the chamber twice as big, and used galvanized pipe instead of black iron. The ammo is AA batteries, metal bar sections, paper darts, mini marshmallows, steel balls, marbles, potatoes, or anything that fits in the barrel. At 120 PSI, I can get a muzzle energy of 100 joul...
by MCRKilljoy
Sat Dec 24, 2016 12:31 pm
Forum: Pneumatic Cannons
Topic: Easy Golf Ball Barrel!
Replies: 0
Views: 3505

Easy Golf Ball Barrel!

I have noticed that a golf ball fits perfectly in 1.5" EMT conduit from the electrical section of a hardware store. You can use an EMT Compression fitting to get 1.5" male pipe threads. EMT conduit has been proven very reliable and can even be used on a hybrid cannon as a barrel.
by MCRKilljoy
Thu Dec 15, 2016 8:39 pm
Forum: Pneumatic Cannons
Topic: The Quick Exhaust Valve (QEV)
Replies: 1
Views: 1007

The Quick Exhaust Valve (QEV)

I wrote an article about using Quick Exhaust Valves (QEVs) and converted it to a PDF to share here. I hope you find the information useful. To open the file, go to the link and click "Download through your browser" and open it with the default PDF viewer. https://mega.nz/#!fkt10BiB!twRL7FL-8mn-R0Ecw...
by MCRKilljoy
Thu Dec 15, 2016 7:56 pm
Forum: Miniature Guns
Topic: Nerf Barrels
Replies: 2
Views: 2069

Nerf Barrels

I just found a great Nerf barrel: 1/2" SCH 80 PVC. It is available as threaded risers at any hardware store. Darts fit perfectly, so it is good for a homemade launcher or modifying an old gun.
by MCRKilljoy
Wed Dec 14, 2016 6:21 pm
Forum: Pneumatic Cannons
Topic: Steel Pipe QEV air gun
Replies: 2
Views: 1501

Re: Steel Pipe QEV air gun

Auxiliary, I used the 1/2" ball valve because I had it lying around. I hold the tank with one hand and pull the valve with the other. The elbow does not make a good pistol grip. The top port of the QEV is where you hook up the barrel. At 150 PSI I shot an AA battery through thick plywood using the 1...
by MCRKilljoy
Sat Dec 10, 2016 10:04 pm
Forum: Pneumatic Cannons
Topic: Steel Pipe QEV air gun
Replies: 2
Views: 1501

Steel Pipe QEV air gun

I built this air gun out of steel pipe. The tank is 1 inch steel pipe, the barrel (not shown) is 1/2 inch copper pipe or 1/2" SCH 80 PVC pipe. The ball valve is the pilot, and you fill with the quick disconnect. I also made a brass adapter to use a bike pump instead of an air compressor. Barrels are...
by MCRKilljoy
Sat Dec 10, 2016 9:56 am
Forum: Pneumatic Cannons
Topic: Never Use PVC!
Replies: 11
Views: 1557

Re: Never Use PVC!

Yes, it's pressure rated... For liquids. Seriously, there's a huge difference between pressure rating something for liquids and pressure rating something for gases. Put it this way: Why do you think hydrostatic pressure testing involves water rather than air? Answer that question and you're well on...
by MCRKilljoy
Thu Dec 08, 2016 11:36 am
Forum: Pneumatic Cannons
Topic: Help with a QEV
Replies: 19
Views: 4131

Re: Help with a QEV

Just buy one. It is about $20 for a good high flow QEV (piston type). Just search on eBay or Amazon. A ball valve is a good pilot valve. It is easy to find and it has high flow, which allows for high power. Use a 1/4 inch or 1/2 inch valve.
by MCRKilljoy
Wed Dec 07, 2016 8:42 pm
Forum: Pneumatic Cannons
Topic: Never Use PVC!
Replies: 11
Views: 1557

Never Use PVC!

Hey guys, PVC Pipe is very dangerous! PVC chambers can explode. PVC is not made for compressed air. So, I used black iron pipe for my pneumatic cannon. I did have a PVC barrel. I shot AA batteries, and since there was no pressure, I thought a PVC barrel would survive. Well, it shattered. My copper b...