im new to piston valves

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canadian
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Sat Jan 27, 2007 9:02 pm

Hey everyone, im new here and have a question.

can you put a return spring on a piston, or will the force of the spring mess it up?

i don't think flow is gonna be a real problem the piston it going to have a very large diameter and a short stroke.

the spring would have to have like 1lb of pressure on the piston
canadian
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Sat Jan 27, 2007 9:12 pm

oh, and the gun will be running over 100psi if that means anything
Hawkeye
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Sat Jan 27, 2007 9:37 pm

I always put a spring in to act as a bumper. You can also save a bit of air if it resets well enough. I usually pump mine up to 160-180 and it resets at about 50 psi. I guess I could just pump it to 120 each time but it seems to be more powerful running at the higher psi. That might be because I don't pay much attention to an optimal chamber barrel ratio.
I have really upped the spring tension and used a shut off in the exhaust to minimize the flow there and managed to get my gun to dry fire nicely about 4 times in a row. Unfortunately when I tried it outside the cold seemed to stiffen up the grease on the piston and it failed to actuate at all.
Even with a spring the piston doesn't seem to be totally sealed until some pressure is added. There is an audible hiss and then a pop as it seals on the first stroke of the pump.. That may be because I use a very hard rubber seal rather than neoprene.
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Insomniac
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Sat Jan 27, 2007 9:38 pm

#1 Read the spud wiki, and use the search button before you ask questions like these.

#2 Edit your posts instead of double posting.

#3 A return spring will work, but it may make the piston slightly less powerful.

Oh and welcome to Spudfiles!
I wonder how much deeper the ocean would be without sponges.
Right now I'm having amnesia and deja vu at the same time. I think I've forgotten this before.

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canadian
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Sat Jan 27, 2007 9:59 pm

Insomniac wrote:#1 Read the spud wiki, and use the search button before you ask questions like these.

#2 Edit your posts instead of double posting.

#3 A return spring will work, but it may make the piston slightly less powerful.

Oh and welcome to Spudfiles!
1. i have, and theres a lot of great info there. (just couldn't find any on return springs)

2. sorry, i'm just lazy

3. thanks.

I've planned out this gun pretty well, thats really the only question i had. hopefully Monday i will have bought all the materials i need to finish it. I'll post my progress. there are some new ideas that i havn't seen done yet that i think will up the performance a bit. I'll make a new post when i start to build.
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Mr.Russ
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Sat Jan 27, 2007 10:28 pm

lol insomniac you like saying that stuff
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