6mm caliber coaxial valve cannon, problems with piston

[makspll]

Hi,

so here is my project: https://photos.app.goo.gl/ClYq6eN5uE853Sdf1
my problem is that when i pump air in, there is leakage through the front of the barrel, the air doesn't stay in the reservoir in the chamber and round the barrel as it should, i don't know if it's the pistons' fault or maybe the center pipe isn't exactly flat and centered, but it looks pretty much perfect so i don't think that's it. so could someone please tell me what should i do to improve the piston ? , i used a rubber tube that is 1mm smaller in diameter to the pipe and added rubber to seal it, it seems pretty tight, after wrapping it in electrical tape for a tighter fit, the leakage still persisted this time the piston didn't move at all which wasn't what i wanted to achieve. PLEASE HELP ME :C I WANT TO GET RID OF MY ANGER THROUGH THE SHOOTING OF SPUDS

[jrrdw]

Check the flatness of the sealing face by putting a light coat of lipstick or alike on the sealing face and use a washer on a bolt and lightly press the washer against the sealing face and check the mark the lipstick leaves on the washer. If it's a good mark all the way around then it's probably the seal it's self not making good contact.

Welcome to Spudfiles!

[makspll]

Check the flatness of the sealing face by putting a light coat of lipstick or alike on the sealing face and use a washer on a bolt and lightly press the washer against the sealing face and check the mark the lipstick leaves on the washer. If it's a good mark all the way around then it's probably the seal it's self not making good contact.

Welcome to Spudfiles!

okay thanks ! and is there any way to fix the alignment without touching the pipe itself ? like by changing the piston ?

[jrrdw]

Use a washer or make a spacer that looks like a washer and match the ID and OD to your cannon. You will have to drill holes in it for air to pass through.

[jackssmirkingrevenge]

Welcome to the forum!

I WANT TO GET RID OF MY ANGER THROUGH THE SHOOTING OF SPUDS

Oh wow, you've absorbed the first rule of Spud Club already!

I would say your piston is definitely the problem. They are difficult to make at this scale especially if you don't have proper tools.

One way to make them is to take a section of tubing that you are using as a chamber, put it in a drill and sharpen it with a file until you get a nice cutting edge. You can then use this to punch out a section of rubber sheet that will be a perfect for your chamber:



As the illustration suggests, one should be careful...

I used this method successfully with many small high pressure projects including my marker gun prototypes.

[makspll]

Use a washer or make a spacer that looks like a washer and match the ID and OD to your cannon. You will have to drill holes in it for air to pass through.

Welcome to the forum!

I WANT TO GET RID OF MY ANGER THROUGH THE SHOOTING OF SPUDS

Oh wow, you've absorbed the first rule of Spud Club already!

I would say your piston is definitely the problem. They are difficult to make at this scale especially if you don't have proper tools.

One way to make them is to take a section of tubing that you are using as a chamber, put it in a drill and sharpen it with a file until you get a nice cutting edge. You can then use this to punch out a section of rubber sheet that will be a perfect for your chamber:



As the illustration suggests, one should be careful...

I used this method successfully with many small high pressure projects including my marker gun prototypes.

cheers guys ! Awesome solutions ! I think this is the best online community I've ever interacted with Thanks for the warm welcome :bounce: