400psi piston vavle

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ALIHISGREAT
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Thu Jan 10, 2008 4:48 pm

POLAND_SPUD wrote:lol I would say that the sleeve valve is even better as a pilot valve than the poppet valve... so what's the problem ?
well the poppet would be an ideal trigger without modding, to make the sleeve valve into a good trigger i will ahve to attach a trigger to it :(
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POLAND_SPUD
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Thu Jan 10, 2008 5:13 pm

i was thinking about this for sometime.... of course the sleeve valve doesn't look as uch as 'normal' trigger as the poppet vavle does..... but I don't think it Makes any difference and sleeve vavle has a lot of advantages - it isn't wasting so much air + it limmits pilot volume.....

but there is one problem connected with this I don't think that pulling the valve to open it is something difficult or akward.... but if you had to push it - I mean when the sleeve valve is place infront of the firing valve (the sleeve valve is closer to the muzzle of the gun than the firing valve/QEV) it would be quite akward.... maybe a pic would help to understand that.... depending on the way you built you gun you have to pull or push the valve to fire
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ALIHISGREAT
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Thu Jan 10, 2008 5:36 pm

yes but i'm guessing it will be fine since rag used one and if it isn;t i wil return it in exchange for a good old ball valve :)

and i'm thinking of using the 1" A and B (first and second) cam and groove couplings for breach loading do you think it will either constrict flow or the body bee too big?

https://vault2.secured-url.com/pneubits ... m_444.html
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POLAND_SPUD
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Thu Jan 10, 2008 6:36 pm

LOL no idea really... you could do it much easier and cheaper IMO... for example use threaded pipe for barrel and voila!! maybe it doesn't look so good but the cost of this stuff is just too big...


BTW I see that all parts, fittings and stuff is VERY expensive in the UK...I've just discovered that QEVs are cheaper in poland than in UK but now I see that fittings are almost 10 times more expensive in UK
for example --- >EQUAL HEX NIPPLE 1/2"" BSPT MALE is £3.64 (Excluding VAT at 17.5%)
while the same thing costs only 1.8 zl + VAT = £ 0.37 here
in poland
WOW I am lucky.... 8)
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ALIHISGREAT
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Fri Jan 11, 2008 2:38 am

POLAND_SPUD wrote:LOL no idea really... you could do it much easier and cheaper IMO... for example use threaded pipe for barrel and voila!! maybe it doesn't look so good but the cost of this stuff is just too big...


BTW I see that all parts, fittings and stuff is VERY expensive in the UK...I've just discovered that QEVs are cheaper in poland than in UK but now I see that fittings are almost 10 times more expensive in UK
for example --- >EQUAL HEX NIPPLE 1/2"" BSPT MALE is £3.64 (Excluding VAT at 17.5%)
while the same thing costs only 1.8 zl + VAT = £ 0.37 here
in poland
WOW I am lucky.... 8)
what type of fitting is that (steel, brass, iron?) what about copper, its £10 for 2m of 22mm in a regular DIY shop but i can get it cheaper off the net.
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POLAND_SPUD
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Fri Jan 11, 2008 2:45 pm

hmmmm after much thinking over this i see Ive made a mistake.... it's not really so much cheaper... I've compared stainless stell nipple with a brass one...
so actually it rather only about 3 times cheaper depending on the type of fitting...

but it is still cheaper so good for me :D
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ALIHISGREAT
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Fri Jan 11, 2008 2:50 pm

POLAND_SPUD wrote:hmmmm after much thinking over this i see Ive made a mistake.... it's not really so much cheaper... I've compared stainless stell nipple with a brass one...
so actually it rather only about 3 times cheaper depending on the type of fitting...

but it is still cheaper so good for me :D
what about iron though, you should comepare with this site http://www.bes.co.uk/index.asp its the cheapest one i have found and it hase awesomely cheap postage :D and i compared prices for 28mm copper off that site and a regular DIY shop and it was nearly ~£4 cheaper i think :shock:
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POLAND_SPUD
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Fri Jan 11, 2008 2:59 pm

wow... great site.... prices are almost the same as in poland... so now you know where to buy :)
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ALIHISGREAT
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Fri Jan 11, 2008 3:37 pm

POLAND_SPUD wrote:wow... great site.... prices are almost the same as in poland... so now you know where to buy :)
what thread do you use in poland? BSP? mybe i could persuade my parents to take me on holiday there when the exchange rate is good and i could come back with tons of cheap fittings :D
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POLAND_SPUD
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Fri Jan 11, 2008 5:22 pm

unfortunatelly.... NPT is used here...

prices here http://www.bes.co.uk/index.asp are really only a little more expensive than in poland... if I were you I would buy all my stuff there...
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ALIHISGREAT
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Fri Jan 11, 2008 5:49 pm

hmm NTP interesting... i would have though BSP just because poland and the UK are closer than the USA and poland :?
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MrCrowley
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Fri Jan 11, 2008 5:55 pm

You can still use NPT with BSP, it's not the end of the world.
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ALIHISGREAT
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Fri Jan 11, 2008 6:27 pm

MrCrowley wrote:You can still use NPT with BSP, it's not the end of the world.
yes i know, although i was told that NTP and BSP threads don't seal very well?
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MrCrowley
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Fri Jan 11, 2008 6:30 pm

I've got them to seal at 120psi, I can't go any higher. But I have full confidence you can get them to seal alot higher.
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ALIHISGREAT
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Fri Jan 11, 2008 6:34 pm

MrCrowley wrote:I've got them to seal at 120psi, I can't go any higher. But I have full confidence you can get them to seal alot higher.
ok cool although i doubt i will ever need to combine NTP and BSP
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