SpudFiles

This is my portable pneumatic,it is full of DWV and I am well aware of it.This cannon has a shreader and Co2 adapter. It has a 1" sprinkler very ergonomic handgrip.

Great job on the gun mate but you better be very, very careful with the pressure you put into it. I can see you put a hell of a lot of work into but the risk is just a bit too high.

Damn shame though...

I handle it with kid gloves and operate at less than 60 psi.

It's still extremely dangerous though. Your playing with fire there mate... I just hope you don't get too badly burnt.

DWV is reasonable in a combustion because there is a small pressure spike on ignition but it can't handle sustained pressure in this application.

Your choice though. Get ready for a slamming by other spudders. We like to do things as safe as possible so another silly kid doesn't do things wrong, get himself killed and then give the people who do things by the book a bad name.

(that silly kid remark wasn't directed at you. Just in general).





Bah sorry about the double post. I thought I clicked edit...

nice cannon, mitch is right, some of the other guys might give you some crap for the dwv parts, but as long as you keep it at lower pressures, its fine. i really like how ergo it looks though. does anyone know if you can get presure rated wyes? (i think thats what the curvy T thing is)

OMG! DWV!

no really, just because its not pressure rated doesn't mean that it can't handle pressure.... (I am not supporting anyone here)

Thats a funky chamber design. If those were Tee's rather than wyes, it would look much better.

rp181 wrote:OMG! DWV!

no really, just because its not pressure rated doesn't mean that it can't handle pressure.... (I am not supporting anyone here)

Thats a funky chamber design. If those were Tee's rather than wyes, it would look much better.

DWV even though not pressure rated is pressure tested for leaks. Is there a plumber in the house who knows what pressure this stuff is tested to? As far as a sustained pressure, I've seen test plugs in place for up to a week and systems under test pressure.

I wish I looked at the test gage when they were testing.

ABS DWV should be good for the test pressure what ever that is.

I have tested 4 inch cellular core DWV at 85 PSI.

I am a framer, but I work around a lot of plumbers (I just scored a bunch of 2 inch copper fittings from a crew the other day when I told them what I wanted to do with them ). The plumbers pressure test their plumbing when they are done to check for leaks. The dial always reads between 20 and 40 psi. They use almost nothing but dwv.

There is no such plumber but remote testing has put my mind at ease.

Nice looks but I wouldnt bet my balls on DWV really. Stay safe mate

god all the people so afraid of DWV, jeez, I have used 1 1/2 abs DWV to over 125 psi, and one day when I get my fridge compressor ready, stupid pressure hose, quick connects and compression fittings

then I will test it to bursting, but for now I trust it.

Back to your gun, the layout is fantastic, actually that is a very VERY ergonomic looking gun, I would just take the sprinkler off, shorten the front bit and make an advanced combustion out of it, that would be sweet.

I think if I get some money, I might consider recreating that as a combustion, (assuming I can convince my parents to let me build one, once I give them the statistics they should crack)

Great gun mate, really, I bookmarked it

Because it's bloody dangerous that's why. Just because you've never had a problem with it, does not mean in any way that it won't blow. I don't even know why it's worth taking the risk...

Sput, making a combustion out of it is a great idea. DWV is great in a combustion application if used in the right way but in a pneumatic, it's just a bit too touchy.

Everyone is their own person and will do what they wish to no matter what anyone says.

I just hope you stay safe mate.

I appreciate the comments and hope everyone realizes that I am not an ignorant fool who will attract bad reputation for the hobby.This design was more of a proof of concept and my latter cannons have been pressure rated.

@Mitchza

I really do not want to do the whole DWV argument that happens unavoidably on every cannon made of DWV, the gun is made, he knows he used DWV, he is using safe pressures. let's leave it at that.

sputnick wrote:@Mitchza

I really do not want to do the whole DWV argument that happens unavoidably on every cannon made of DWV, the gun is made, he knows he used DWV, he is using safe pressures. let's leave it at that.

Agreed, I tested this personally as I wanted to see if ABS was good to use for barrels. My test unit failed to burst even though I put the fill in the side to create a weak spot. I tested to 85 PSI, then used it every year at a church camp to launch apples at up to 65 PSI. This is my first quick dump valve cannon, now 7 years old and still working. It gets a new pressure test every year.

***Edit*** This has out lived 3 PVC quick exhaust valve cannons that have failed. For lower pressure ABS DWV appears to be much more shatter resistant and it doesn't gernade when it fails.

I don't use PVC anymore for compressed air storage. I don't like the failure mode.