pressurizing my pneumatic

Show us your pneumatic spud gun! Discuss pneumatic (compressed gas) powered potato guns and related accessories. Valve types, actuation, pipe, materials, fittings, compressors, safety, gas choices, and more.
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pizlo
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Tue Dec 26, 2006 6:00 pm

Well i got my first pneumatic gun glued a couple of days ago, i have a design mostly like killas tutorial. the first thing i did was try to get some pressure with my hand bike pump... and my gauge showed nothing, I knew i had pressure because i could get a 1in core of a spud about 30 ft. after trying a 12 volt car tire inflater for about 2 minutes i got the same results. after i checked for a leak and found one around my valve. i sealed this up with some gorilla glue witch is now airtight. but I cannot seem to get my psi above 10 or it would show on my gauge. what should i use to get the psi to at least 60? thanks.
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Pete Zaria
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Tue Dec 26, 2006 6:03 pm

Assuming you don't have any electronics (Such as a solenoid) on your gun, I say pump it up as high as you can currently get it, and leak test it underwater in your bath tub. I'm suspecting you have a leak somewhere.

What kind of valve do you have? If you have a diaphragm or piston, you may need to check the seal and/or lubricate it.

Give us more info.

Peace,
Pete Zaria.
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jrrdw
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Tue Dec 26, 2006 6:36 pm

I think you should pump it up again, and tap on your pressure guage with your finger. Your probly getting a false reading.
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pizlo
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Tue Dec 26, 2006 9:36 pm

yea i tried tapping the gauge and nothing, i am using a pvc ball valve any ideas on what i should use to inflate it my bike pump is not great but it does my bike tires just fine
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Bluetooth
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Tue Dec 26, 2006 9:38 pm

Your either very very weak or your bike pump is messed up. Go buy a compressor and rebuild you cannon so you can use it :lol: .
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Insomniac
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Tue Dec 26, 2006 9:46 pm

Maybe your gauge is busted????
Buy a cheap guage that you just fit on the schrader to get the pressure ( you can get them at bike shops) and see if the gun is holding pressure.
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frankrede
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Wed Dec 27, 2006 2:41 am

yest your guage on your bike tire, if it shows no pressure then your pump is fine.
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experament-u2
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Wed Dec 27, 2006 3:23 am

i think ure psi guage is buggered just by a hole new pump or borow one and test it
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killagorrila99
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Wed Dec 27, 2006 3:30 am

like killas tutorial
Can I see some pics. I'm proud of my tut.
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Wed Dec 27, 2006 7:13 am

Sounds to me like it's a problem with your Schrader, (tire), valve. They do that to me occasionally. They get up to a certain pressure and then disconnect. I don't know for sure, but you may want to check that.
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pizlo
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Wed Dec 27, 2006 10:23 am

i can post some pics later (by the way killer i liked your tut, i used 1 in pipe for the barrel instead of 3/4.) the gauge is 0-300 psi, and is 1/4 in thread, its screwed into a a threaded metal reducer,which is screwed into a 1/2 in threaded pvc reducer, all these i screwed in with Teflon tape the correct way. I know i had a little leak around my tire valve,(i got it up to pressure then painted all the joints with soppy water.) I "fixed" this by pushing the valve part way in a applying some gorilla glue, i also put some around the outside. once this dried it stopped the leak , i also put some duct tape over it in case there was a very minor leak. my uncle told me that a gauge that goes in ticks of 10 psi might not move unless it reaches 10psi, i might have not reached 10 for some reason, because i could only get the spud core about 30 ft.
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