Help QEV Sprinkler valve trouble

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Maasoon
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Mon Jul 22, 2013 5:01 am

Hey everyone i have recently started to build my first pneumatic spud gun as i have only ever built propane ones before. I purchased a solenoid sprinkler valve and have epoxied the solenoid cavity and attached a blow gun with a brass nipple as a guide on you tube suggested. The problem i have is that air still flows out of the barrel not quickly but at a noticeable pace also the blow gun does not increase the air flow when triggered. i was reading so threads about how a bigger equalizing hole would help but i don't think mine even has one. what should i do should i poke a pin through the diaphragm? to crate one?
Thanks Mason
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jackssmirkingrevenge
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Mon Jul 22, 2013 5:17 am

Photos of your setup?
hectmarr wrote:You have to make many weapons, because this field is long and short life
Maasoon
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Mon Jul 22, 2013 5:22 am

its just a 1" sprinkler valve with a normal blow gun screwed in
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jackssmirkingrevenge
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Mon Jul 22, 2013 5:52 am

what model sprinkler valve?

can you take pictures of how and where you installed the brass nipple?

It's hard to give advice without looking at the thing.
hectmarr wrote:You have to make many weapons, because this field is long and short life
Maasoon
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Mon Jul 22, 2013 6:42 am

I don't know how to upload photos but I can email them[/img]
Maasoon
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Mon Jul 22, 2013 6:47 am

Emailed them to you to the address on our profile
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jackssmirkingrevenge
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Mon Jul 22, 2013 8:00 am

You seem to have done everything right, my feeling is that you are not filling the chamber fast enough. Are you sure there was no dirt on the diaphragm when you put it back together?
Attachments
valve1.JPG
valve2.JPG
hectmarr wrote:You have to make many weapons, because this field is long and short life
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dewey-1
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Mon Jul 22, 2013 9:38 am

Also need pictures of spring location and diaphragm which may help.
What brand and model is the sprinkler valve?
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jackssmirkingrevenge
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Mon Jul 22, 2013 1:11 pm

here you go
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valve5.jpg
valve4.jpg
valve3.jpg
hectmarr wrote:You have to make many weapons, because this field is long and short life
Maasoon
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Mon Jul 22, 2013 4:07 pm

I'm using a compreser and I have tryed a hand pump. If I think I know how these work, shouldnt the area above the diaphragm be the same pressure as the air tank? If so I don't think its happening in this valve is the diaphragm is completely air tight. Even when I block the barrel side and open the blow gun no air comes out. Could it be that with no air going in above the diaphragm that it is a lower pressure there already and the diapgram moves slightly up allowing small air flow??
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dewey-1
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Mon Jul 22, 2013 4:41 pm

What brand and model?

Is there a hole in the center of the diaphragm with a screen in it?
Maasoon
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Mon Jul 22, 2013 4:52 pm

No should I drill one? There used to be a hole for a guide rod right in the center but I epoxed it :/ it was maybe 1-2mm big
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dewey-1
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Mon Jul 22, 2013 7:00 pm

Yes, drill out that epoxy with about a 2.0mm drill,
You need an equalization hole.
Maasoon
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Mon Jul 22, 2013 8:00 pm

Its dead in the center in the plastic and does that mean the tank connects to the side where the inlet connects to the equalization hole yeah?
Maasoon
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Thu Aug 01, 2013 5:34 am

Hey everyone sorry to bump the thead but i kinda have it working. I drilled out the epoxy and it works well at 30-35 psi i have a resonbly small tank just the stock. I have pressued it to 120 psi however the valve does not fire correctly. It kinda just vibrates and makes a honk noise and the projectile will just fall out the end of the barrel.any ideas on how to fix? Is the equalization hole to big its 1mm atm
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