Yet another basic spudgun

[Fish8myb8]

Hello, spudders. I'v been looking all around the net for help on making my first spudgun, and Spudfiles seemed to be the answer to all my questions. Another week of lurking, and Mark 1 came to be.

Specs:
-24 inch copper barrel
-ball valve release
-10" by 2" chamber

Updates to come:
-bolt action (gotta borrow a Dremel)
-conversion to sprinkler valve (as soon as I find all the parts I need on one website)
-wooden body stock (the last thing I'll do)


Pictures:





What I pump this thing to 100 psi with:


where the bolt is to be cut. A repair couplling goes over the gap, which is a nice, snug fit over the barrel. Ideal for a 'bolt' in my opinion.


The most sensitive part of the gun. Glued a bike tire Schrader valve inside the cleanout plug with epoxy. Leaked before, so I sanded out the inside of the hole and downed that thing with epoxy. Put the pump on and had to pump air through it as it dried so the epoxy wouldn't cover the hole in the valve.




Decal never hurt


Broke a ceramic pot about 1/2" thick with a 9mm round casing at about 20 feet away.[/url]

[rikukiakuchiki777]

Cool launcher!

What parts do you need to upgrade to a sprinkler valve system? Apart from the sprinkler itself do you need much more?

I daresay you would be significantly impressed with the sprinkler valve's performance as opposed to a manually actuated ball valve, so I would recommend working on upgrading it as soon as possible

[deathbyDWV]

Looks good but just a warning... That style of back plug you have is almost NEVER pressure rated. That schrader will make it even less strong. What pressure will you plan on using?

Other than that it looks good! Good luck on getting the sprinkler valve soon...

[starman]

Looks good but just a warning... That style of back plug you have is almost NEVER pressure rated.

I'll second that warning. You should just use a pressure rated endcap on that back end of the air chamber instead of that socket/NPT adapter. Also find a different location to install the schrader valve...typically through two layers of PVC.

Otherwise, welcome to Spudfiles.

[Crna Legija]

nice gun you don't need much more parts to go sprinkler valve are you going to mod it ?

the cap at the back is not safe i have had them blow out on spray n pray combutons that only make 40ish psi using it at 100 ant good at all maybe put some screws thru it

[MrCrowley]

the cap at the back is not safe i have had them blow out on spray n pray combutons that only make 40ish psi using it at 100 ant good at all maybe put some screws thru it

I'd do more than put a screw through it. DWV fittings have short socket depths, not to mention their thickness. So the whole fitting should be replaced, and any other DWV fittings/pipe.

Fish8myb8,

Read this:
http://www.spudfiles.com/spud_wiki/inde ... sure_rated

Otherwise, nice starter cannon. You should plan your next one soon

[jackssmirkingrevenge]

Otherwise, nice starter cannon. You should plan your next one soon

Yep, and if you want to stay with a relatively small calibre forget the sprinkler valve and think QEV + higher pressures

[Fish8myb8]

Holy crap, that reply was fast! thanks guys!

Alright, I know for sure that that black tire valve has to go. In fact, it flew out on its own yesterday. I don't know how I should attach the valve any other way -- or if there's another way of getting air in it. I just thought of getting a valve off McMaster with a 1/8 npt male fitting and screwing it into a reducer bushing that goes onto the end of that chamber.

@rikukiakuchiki777,
I need to get the sprinkler valve, and an adapter, and a grippy-valve to release the diaphragm pressure.

@deathbyDWV,
Thank you! usually at 100 psi.

@starman,
Thank you very much for the help.

@-_-,
Put a screw through the rubber part to keep it firm against the cleanout plug? I would if it didn't fly out -_-

@MrCrowly,
Thanks, I'll be sure to get all pressure rated parts for my next cannon, which is only maybe 2 weeks away.

@jackssmirkingrevenge,
Read a lot about QEV's, where can I buy one compatible with a cannon?
I don't just wanna stick with small calibers, I want to try it all now that I'm hooked to this

[Hubb]

Man!! This thing is a DWV beast. Front coupling, female adapter, plug...

If you're looking to replace your blown tire valve with a threaded schrader, look in a hardware store near the air compressors. It can usually be found there and has 1/8" NPT threads. The threads can be cut directly into the PVC or you could add a few more fittings to do it. It would probably just be easier to go through the PVC, just make sure to go through two layers (say, on the coupling and through the pipe).

For better performance on the valve, try spring-loading it. It will open much faster and more uniform.

And you could never go wrong with a sprinkler valve. (Check the Hubb Library to find out more!!)

[Fish8myb8]

Man!! This thing is a DWV beast. Front coupling, female adapter, plug...

If you're looking to replace your blown tire valve with a threaded schrader, look in a hardware store near the air compressors. It can usually be found there and has 1/8" NPT threads. The threads can be cut directly into the PVC or you could add a few more fittings to do it. It would probably just be easier to go through the PVC, just make sure to go through two layers (say, on the coupling and through the pipe).

For better performance on the valve, try spring-loading it. It will open much faster and more uniform.

And you could never go wrong with a sprinkler valve. (Check the Hubb Library to find out more!!)

Most helpful comment yet, thank you very much. To thread the schrader through the 2 layers, I need to thread the hole I drill in the 2 layers first, right? Drill a regular hole a bit smaller than the diameter of the schrader, and then put the schrader into the drill chuck and slowly thread the hole?

All the fitting I used have on them somewhere NSF-PW, SpudWiki says stuff that has NSF-PW on it has been pressure rated?
Everything but the cleanout plug has NSF-PW.

Thanks, really helped!

[MrCrowley]

Yes that is correct, NSF-PW parts are pressure rated.
What I think Hubb is talking about is that the front bushing and coupler aren't really pushed together very well, this is usually a sign of DWV. DWV fittings have short socket depths (how far a fitting can fit inside of another one), which is another reason why they are dangerous.

Sometimes it's easier to get fittings to go inside of one another if you twist them while you push them together, this also helps create a stronger bond with the PVC glue and fittings.

[Fish8myb8]

It's most likely the coupler is DWV then because when I put this together, I put it perpendicular to the ground and put all my weight on it after twisting as I squeeze like you said. Woaw, this is a lot of things I did not know about before. Next launcher will definitely be made with more thought and knowledge involved. Thanks.

[Hubb]

I wouldn't chuck the schrader. Drill a slightly smaller hole than the schrader (I forget the size I use), then work the schrader in with a wrench or pliers. Turn it in a little, then back it out. Repeat this until it is completely threaded. Once done, remove it and wrap it with teflon tape or put epoxy around the threads, then place it back into the hole.

[Fish8myb8]

Alright, thanks Hubb. Great stuff in your Library, by the way. Rifling the barrel soon, and now I know for sure what to do with a sprinkler valve once I get one.