SpudFiles

I Just finished building an air-powered sprinkler-valve spud gun and I have a slow leak. After checking all of the pipe fittings (i used galvanized and black pipe for the air tank) I decided to clean out the valve in case some dirt found its way into the diaphragm. It looked clean, but I took some "magic lube II" (get your mind out of the gutter!) and smeared some around all of the rubber parts that contact the plastic housing.

Magic Lube II is used for things like pool/hot tub fittings to help them seal up without any adhesion. I'm pretty sure any silicone lubricant would work (pick some up at your local hardware store in the plumbing dept). I fired my cannon about 10 times after doing that and I haven't had any 'goose' sounds and I find that I can load my barrel before filling because no extra air escapes through the valve.

I haven't found where my slow leak is (any suggestions?), but at least I'm making some kind of progress.

You can mix dish washing soap and water and spray it on all the connections. The leak will blow bubbles.

"Honking" can be a result of inadequate piloting, what valve are you using as a pilot, and have you attached it to a long length of hose?

find that leak mate.. if it's on the pilot side that gun could fire on it's own.

http://www.spudfiles.com/forums/the-spr ... 16786.html

Everything you need to know about sprinkler valves and more

Fill up your bath tub and throw your cannon in there and look for the bubbles. You will find your leak!!!!

I'm not concerned about the leak, i'm modifying my holding tank tomorrow when i get some parts from work, so i didn't spend a lot of time tracing that down. I went over all of the fitting with soapy water when i charged it the first time, but the leak is very slow so i wasnt able to see any bubbles. After I expand my holding tank i'll be dunking the whole thing in a 5-gal bucket to look for leaks. I built my tank out of galvanized pipe so i could use higher pressures without any safety concerns, so its a fairly small holding tank (its small enough to carry around easily), so i'll be able to fit it in a bucket.

I also forgot to paint the inside of my steel pipe (rust is the enemy!), so i need to take it apart and do that.

I did find that when my valve 'goosed' it did let a little bit of air through, which meant i'd have to charge the tank first, then load ammunition. Now I can load first, then charge. This way is much better and safer.

I always charge first, then load. This way is safer because if the cannon is accidently triggered, there is no projectile to worry about. Just my opinion!!

What if your pilot valve leaks, or worse, bumps and breaks while your loading??

I had a leaking pilot once when fellow member Psycix viseted me..

The aluminium blowgun I had sold him had a crack at the connection wich was not noticed before.When we charged it up to a pressure he hadn;t been able to reach before the the crack started to fail..
We kinda knew what was coming so I pointed the loaded gun to a brick wall and sure enough it fired.

needless to say I supplied him with a new pilot valve..

Load first, then pressurise while pointing in a safe direction!