My first pneumatic - updated with damage pics

[Blitz]

Could you take a picture of your new piston?

[cerberus]

New piston pic added

[mega_swordman]

I see you aren't a sniper . Just kidding. A very nice cannon, and a very interesting trigger system. Good Job!

[cerberus]

Things just got very interesting. I eventually got around to replacing the piston I had thrown together to replace the broken one with a proper Neoprene piston. The last piston was made of a high density foam which leaked a little and opened slowly, the neoprene however, with a small amount of vegetable oil for lubrication, made a huge difference and the piston now opens much faster with almost no differential in pressure.

The result? The back fence of my yard used to stop the marbles fired from 10m away with a small dent, now the marbles go straight through the fence and embed themselves if they hit one of the 2x4s. Unfortunately this means I can no longer fire my cannon in my backyard.

Who would have thought the piston construction could have such a huge impact.

[DannyGlover666]

Nice combustion man.

[mopherman]

Nice combustion man.

This is a pneumatic cannon. It does not use cobustion for power. It uses compressed air through a valve.

[windshrike]

My first pneumatic

It's a pneumatic; it uses compressed air to launch the projectile, not the rapidly expanding gases of a deflagration that a combustion does.

@cerberus: Beautiful gun, amazing for a first pneumatic. Most people start out with ball and sprinkler valves, but you have gone straight to a piston

[cerberus]

Cheers windshrike, I actually upgraded it a while ago but never got up to loading new pics. The trigger mechanism I was using caused the barrel to move a lot making shots unpredictable and inaccurate. To avoid this I went down the much trodden path of a sprinkler valve and window washer. The power gain is a pleasant side effect. The only catch is that now there is significant air flow from the rear of the gun which makes earmuffs a must if firing with the gun at the shoulder.

As an aside I now shoot at 150 PSI.

[MrCrowley]

I see you put the trigger in place of the solenoid, I hope you drilled a bigger flow hole as it's usually only around 1/32".

I would recommend placing it in the normal position in the middle and drill your own hole.

[cerberus]

I did, the hole was drilled out to 5mm (1/5") which has proven to be more than enough. The reason I placed the trigger over the existing solenoid hole was to avoid having to remove the guide rod. Despite what a few people have said I believe it is necessary to ensure the diaphragm seats properly.

[Mpeddlesden]

hey. would you be able to send me a hot to print of your gun
(insain-93@hotmail.com) i have been trying to make one like yours for ages now.

[jackssmirkingrevenge]

I have been trying to make one like yours for ages now.

If you can't figure out how to make it from the photos then you should probably start with something simpler...

[Crna Legija]

nice gun for a first real clean. by eny chance do you play silkroad