filling a piston

Cannons powered by pneumatic pressure (compressed gas) using a valve or other release.
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covey12
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is a rapid amount of air need to fill a 2" piston, because i have the feeling my bike pump is not putting out enough air to even push the piston, should i save up and get a cheap compressor?
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spudtyrrant
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i have used a bike pump to fill up my 2 inch piston cannon maybe you piston isn't tight enough add some teflon tape around it and try again :wink:
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Technician1002
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covey12 wrote:is a rapid amount of air need to fill a 2" piston, because i have the feeling my bike pump is not putting out enough air to even push the piston, should i save up and get a cheap compressor?
A smaller EQ port or a better seal is required. Until 2 weeks ago, all my cannons were hand pumped. My hand pump died and I bought a very small compressor for $60.

Could you post details on the 2 inch piston cannon? How is it sealed? Is it filled through the pilot? Photos are helpful.

Attached is a photo of a 2 inch piston under pressure test with a hand pump.

Problems with the piston sealing face can also prevent filling as the valve will fail to seal against the barrel. What are you using for a seal? Is the valve seat true and polished flat?
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Pressure testing the 2 inch piston ABS cannon.
Pressure testing the 2 inch piston ABS cannon.
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covey12
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yea i did have quite a bit of clearance around the piston now that i think about it, probably about .5mm from the piston to housing, is that to much? it is barrel sealing t-piston

btw on my new piston if i just put screws threw the tee and the end cap will it be air tight, this way it will be serviceable
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Gaderelguitarist
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To use a hand pump with that piston you could easily put a light spring behind the piston.

I don't even bother with trying to make socket fittings serviceable. It's caused me too much wallet ache in the past. But don't let that discourage you. It does work, it's just not for me i guess.
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jmccalip
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Well, my 3" piston uses a homemade check valve, and that seems to do the trick. I have not tried it with a bike pump, but it can fill with almost no flow(I used a air regulator).
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