Eureka! Ready Built Pumps!

Threads about how water guns work and other miscellaneous water gun technology threads.
atvan
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Re: Eureka! Ready Built Pumps!

Post by atvan » Fri Jul 29, 2011 6:23 pm

He is talking about a homemade nerf guwhere if you but your palm over the barrel, the plunger will only go halfway, then stop, because of a perfect seal.

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C-A_99
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Re: Eureka! Ready Built Pumps!

Post by C-A_99 » Fri Jul 29, 2011 7:40 pm

Air pumps are designed with a dent in the O-ring groove, so that when pumping downwards, the O-ring is pushed outwards to seal, then the O-ring is relaxed so that the pump can be pulled without trouble. This part needs to be modded, or it will not seal with water.

Stock Nerf plungers have very lousy seals. Haven't worked with modded/homemade plungers, but apparently they work with a perfect seal. I wonder if the same is true for Airsoft plungers. The only one I've seen (which was broken anyway) didn't seal much better than a stock Nerf plunger.

atvan
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Re: Eureka! Ready Built Pumps!

Post by atvan » Fri Jul 29, 2011 9:54 pm

DX said his "perfect" seal nerf homemade barely held water at all.

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DX
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Re: Eureka! Ready Built Pumps!

Post by DX » Thu Aug 04, 2011 3:46 am

That was a PAS, a manufactured gun. The seal is still tight enough to vacuum load darts from CPVC fit, and the plunger will stop dead when covered, so it's virtually perfect. Water still ended up pouring out of the back casing from the trigger area though. My homemade has essentially a perfect seal, but I'm not willing to test water in it as it's my primary and I have no other top of the line homemades, nor any idea how to take it apart if a piece were to get wet and later rust.

The problem with bike pumps is that they are expensive, so if you break it, you just wasted a load of money. Those $20 floor pumps are not even worth buying because they break quickly. I have a racing bike and have gone through several in rapid succession even just pumping air at normal speeds. $40 floor pumps last longer, and my $60 one has lasted several years so far. The little handheld pumps just suck.
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zeda.beta
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Re: Eureka! Ready Built Pumps!

Post by zeda.beta » Mon Aug 08, 2011 7:05 am

My airsoft guns don't have a perfect seal by any means, probably for the reasons described earlier. However, one that I replaced the bolt on does have a perfect seal, but the barrel is open to compensate.
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