Presta Vs. Schrader.

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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neeewwww
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Wed Jul 08, 2009 11:27 am

Hi there...

Yesterday I just finished my piston housing, and my piston... I didn´t do a real "test" on it... Just but my mouth at piston housing and blow air... the piston slides smoothly, but there´s a small leak to the barrel (Barrel sealing piston).

So I need a "high" pressure test... Today, I bought a floor pump rated 7Bar (I guess it will break after some months)... And went to a bike store...I just ask for a Schrader Valve, but the guy show me some, all had a rubber body around the valve... No screws...
So I explained what I need, and the guy show me a presta valve... So I bought it...
Firts time, I was wondering how to "use" a presta valve... And after like 5 minutes I realized how it works...

So guys, the question is...
Whats the matter with Presta Valve (as soon, I never saw a Presta Valve here).
The difference is just a spring that shuts the air on Schrader? I took a look at some Bike Forums, presta valve are the option for those guys...

Tell me the Pros and Cons... please.
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frankrede
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Wed Jul 08, 2009 11:29 am

Presta valves are not fun to fill if you have to use an schrader adapter, and they are quite delicate.
As a exaust they work great though.
Current project: Afghanistan deployment
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neeewwww
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Wed Jul 08, 2009 11:32 am

I use presta as my inlet...
I bought too an adapter... Its just like a nut.

Yes, sure, they are quite delicate... But, I didnt find any cons, except its building...

o>
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Hubb
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Wed Jul 08, 2009 11:34 am

The only difference (that I know of) is that a schrader has a spring in it.

As far as finding a threaded one, a bike shop is not the answer. Check the local stores for air fitting supplies. They are usually found there. Also, BCArms sells them.
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neeewwww
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Wed Jul 08, 2009 11:37 am

@hubb017 - Yes thats the only difference I guess... The spring thats shuts the outlet air... Presta valves, the valve shuts from the outlet pressure, more pressure, more tight close...
I check everywhere for threaded schrader valves... But I just found the "flat" ones... BCArms offline...

* I live in Brazil x)


o>
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POLAND_SPUD
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Wed Jul 08, 2009 7:35 pm

why do you need a presta/shrader ? if you need it for filling the gun then consider switching to quick connect fittings (they are used on most pneumatic tools and compressors)

a female fitting is normally attached to the pump/compressor and male fitting to the gun
(you'll need a ball valve in between the piston valve and the QC fitting...)

once you fill the gun you close the BV and disconnect the gun... to fire the gun just open the BV


these things are much simpler to use than shrader adapters
Children are the future

unless we stop them now
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frankrede
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Thu Jul 09, 2009 12:05 pm

launchpotatoes.com
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