Simple inline cannon

[Marffy]

One day i wanted to make a cannon that was a total upgrade from the rest of my cannons. so i made an inline knowing that that would be the most powerful design choice. This cannon is great! it can stick a nail dart an inch into a health tree And explode an apple against a tree at only 20psi.The cannon is over 5ft tall with my 2" barrel. I have a 1/2" bolt action barrel, a 1.5" barrel, a 1inch thin wall barrel, and a 3/4" barrel. It has one problem though... the sprinkler valve leaks. It is leaking between the two plastic parts of the valve and out of the barrel of the gun. if anyone knows how i could fix it or something let me know.

This is my first cannon post so go easy.

New video is up!
[youtube][/youtube]

[tghhs]

Awesome well done.

I'm interested about the grey barrel and tank, is it sch80?

When you modded the valve ther may have been some dirt or stone or something of that nature that may have gotten in stopping the perfect seal. Just pull it apart again and give it a good clean, making sure theres nothing on the seal or daiphram.

also after you've done this check seals around the outside and put it back together tightly.

[jackssmirkingrevenge]

The chamber seems a little overkill for such a stumpy barrel, but otherwise not a bad job.

[Marffy]

The chamber seems a little overkill for such a stumpy barrel, but otherwise not a bad job.

yes it is overkill for that barrel. i have much longer ones tho.

[Marffy]

Awesome well done.

I'm interested about the grey barrel and tank, is it sch80?

When you modded the valve ther may have been some dirt or stone or something of that nature that may have gotten in stopping the perfect seal. Just pull it apart again and give it a good clean, making sure theres nothing on the seal or daiphram.

also after you've done this check seals around the outside and put it back together tightly.

no, its not sch80 its just this conduit kind of stuff i found in my shop.Do you think the leak could be somthing to do with the connection between the plastic and the blowgun? all i use was tefflon and a spade bit. no tapping at all.

[pyrogeek]

Definitely get a longer barrel. You're not getting the potential out of that large volume of air in your chamber.

Do you have a spring in the valve? How big is your equilization hole thing in the valve? A little larger hole can make it seal faster, which could be an issue with that big of a tank. And if you aren't going to tap the hole before threading in your thing to pilot it, use some JB Weld or epoxy or something to seal it.

[chinnerz]

super simple design, i like it,
>>however i think a shot of matt black would work wonders for the looks department

[Marffy]

Definitely get a longer barrel. You're not getting the potential out of that large volume of air in your chamber.

Do you have a spring in the valve? How big is your equilization hole thing in the valve? A little larger hole can make it seal faster, which could be an issue with that big of a tank. And if you aren't going to tap the hole before threading in your thing to pilot it, use some JB Weld or epoxy or something to seal it.

yes there is a spring in the valve. i'll try some apoxy all around. and i have tons of barrels for this thing.

[deathbyDWV]

Since that is the same type of sprinkler valve I use... One part that could be leaking... It you take the top off then look on the inside of the top piece. There will be a small white spigot type thing that sticks into the bottom assembly. It also has an o ring around it. This should be covered in glue from the top but sometimes the glue doesn't get inside this. this can cause leaking from the chamber, through the equalization hole of the diaphragm, then out the barrel through the origional pilot hole.

To fix it you can put some super glue or something into the small hole from the bottom side.

Even if this isn't the problem, it won't mess anything up if you try it.

[jmadden91]

its just this conduit kind of stuff

Not a good idea at all. Keep the pressures down mate

Edit: lol btw cool cannon. If i were you I would cap the barrel and put a fill valve in it, and use your chamber as the barrel. Maybe not quite that drastic but as everyone is saying cut down on chamber size, and/or get a longer barrel. You'll be pleasently surprised

[Marffy]

its just this conduit kind of stuff

Not a good idea at all. Keep the pressures down mate

Its pressure rated i belive soo.....

[MrCrowley]

Are you sure it's pressure rated? Are there any markings on the pipe that lead you to believe it is?

[Marffy]

Are you sure it's pressure rated? Are there any markings on the pipe that lead you to believe it is?

it says in yellow: sch40 conduit pvc

i spray-painted most of the writing so yeah...

[MrCrowley]

Are you sure it's pressure rated? Are there any markings on the pipe that lead you to believe it is?

it says in yellow: sch40 conduit pvc

i spray-painted most of the writing so yeah...

Who ever is responsible for telling people that SCH 40 means pressure rated, I would like to meet them and give them a hiding.

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

Doesn't look good, sorry. I haven't heard of pressure rated conduit personally.

[Marffy]

Are you sure it's pressure rated? Are there any markings on the pipe that lead you to believe it is?

it says in yellow: sch40 conduit pvc

i spray-painted most of the writing so yeah...

Who ever is responsible for telling people that SCH 40 means pressure rated, I would like to meet them and give them a hiding.

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

Doesn't look good, sorry. I haven't heard of pressure rated conduit personally.

i guess i'll keep the pressure lower. ive been putting it up to 120psi with no problem. i guess ill have to make a protecting thing that goes around it