deadspace

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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POLAND_SPUD
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Thu Feb 07, 2008 4:14 pm

I tried several configurations of my qev gun... and I suppose i found one that is ergonomic and easy to aim and fire....

the only problem is that this setup has two 1/2" 90 degree elbows on the exhaust side before the barrel starts (of course there are two 1/2" nipples there too)...
I am a little worried that it may be reducing the gun performance significantly..... should I really worry about this ? anyidea how much does it reduce the power ?
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Thu Feb 07, 2008 4:30 pm

It won't account for the actual pressure loss due to the bends, but GGDT can calculate the effect of the dead space. My guess is that it won't really matter much unless your chamber is really small. In some cases more dead space can actually increase performance.
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dewey-1
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Thu Feb 07, 2008 4:39 pm

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POLAND_SPUD
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Thu Feb 07, 2008 5:02 pm

currently my gun is configured like this... thep ilot side consist of 1/2" T with a BV and a quick-connect fitting
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dewey-1
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Thu Feb 07, 2008 5:40 pm

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*5*STAR*GENERAL*
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Thu Feb 07, 2008 7:42 pm

ther will be a loss in accuracy becuase dead space creates the spinning or unbalance of air flowing but the power of the cannon will be not phased to be noticed. :lol:
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bigbob12345
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Thu Feb 07, 2008 7:48 pm

How would there possibly be a loss of accuracy the air doesnt spin in circles it just rushes out so it can equalize itself.
POLAND_SPUD you will not see any accuracy decrease and hardly any power deacrease so if that is the most comfortable way to hold it do it it wont affect performance by any noticable degree.
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Ragnarok
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Thu Feb 07, 2008 8:00 pm

*5*STAR*GENERAL* wrote:ther will be a loss in accuracy becuase dead space creates the spinning or unbalance of air flowing but the power of the cannon will be not phased to be noticed.
Where in blazes does this guy come up with this nonsense from?

Sorry, but it seems like you procure this information from your colon. It's nothing strictly against the rules, but it's inaccurate, confusing to newbies (heck, you confuse me - because I try to work out whether you learnt this garbage, or you're just coming up with it), and one day you may say something that could cause someone to get hurt.

I implore you to stop this ridiculous bluffing - it buys you no favour with the people that know it's male bovine excreta - it's a waste of everyone's time, and it could be dangerous.

@POLAND_SPUD & bigbob12345: Ignore 5 Star General - of all his posts, I have never seen one that contains useful and accurate information.
It's nothing he can be banned for, but as far as I can tell he's a total n00b who's trying to talk clever and failing miserably.
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Thu Feb 07, 2008 8:01 pm

If you want to figure out space of a 90 degree elbow.. Its 1.5X the diameter of the pipe.


so a 2" elbo would be 3" of pipe a 45% bend would be 1.43--
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bigbob12345
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Thu Feb 07, 2008 8:15 pm

Ragnarok wrote: @POLAND_SPUD & bigbob12345: Ignore 5 Star General - of all his posts, I have never seen one that contains useful and accurate information.
It's nothing he can be banned for, but as far as I can tell he's a total n00b who's trying to talk clever and failing miserably.
I just had a look over all his posts and not a single one of them was true or made any sense in any way as you noted.
I agree entirely that he could give someone bad info and cause someone to get hurt/killed and i think that makes him viable for a ban as he is a danger to any new person coming on this forum that doesnt know his cluelessness.

And 5 Star general if you really want to be an expert but arnt just become one do some reaserch make a couple cannons learn the concepts of C:B ratios,piston valves,and so on.
after that you may be viable to give out some good information and actually mean something on this forum.
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potatoflinger
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Thu Feb 07, 2008 8:26 pm

Why not just turn the QEV around so that the pilot setup is to the right and the barrel comes straight out to the left, with no bends. (I am referring to your design where the barrel comes out the right side, but then turns 180* and goes to the left.) The problem would be solved by simply turning the QEV 180* more.
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jackssmirkingrevenge
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Thu Feb 07, 2008 10:40 pm

Without a chrony you probably won't see the difference.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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POLAND_SPUD
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Fri Feb 08, 2008 1:46 am

@ *5*STAR*GENERAL* yeah I know that, but i am using homing pigeons with this so it is not a problem :-D

thx for your answers...
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