Login    Register
User Information
Username:
Password:
We are a free and open
community, all are welcome.
Click here to Register
Sponsored
Who is online

In total there are 66 users online :: 3 registered, 0 hidden and 63 guests


Most users ever online was 155 on Mon Aug 15, 2016 1:40 am

Registered users: Bing [Bot], Google [Bot], Yahoo [Bot] based on users active over the past 5 minutes

The Team
Administrators
Global Moderators
global_moderators.png CS

QEV wont work

Post questions and info about pneumatic (compressed gas) powered cannons here. This includes discussion about valves, pipe types, compressors, alternate gas setups, and anything else relevant.
Sponsored 
  • Author
    Message

QEV wont work

Unread postAuthor: Cosmic Muffin » Thu Jan 20, 2011 8:33 am

hey all, i bought this off ebay the other day and realised the pilot thread is 3/8in. so i epoxied a 1/4in a 9bar pop off valve. and used that to actuate it. but it just wont work... i bought a QEV so i wouldnt have to stuff around with pistons and things because i can never seem to get it right. so im very frustrated that it wont work. any ideas as to why?

http://cgi.ebay.com.au/Pneumatic-Quick-Exhaust-Valve-1-4-NPT-Ports-Aluminum-/260415393436?pt=Pneumatic_Hydraulic_Valves_Parts&hash=item3ca1f78e9c my mistake.. this is the one

EDIT
sorry bout the double post, been off spudfiles for so long ive forgotten the forum rules ><

Edited by jrrdw, fixed link double post.
  • 0

User avatar
Cosmic Muffin
1st Lieutenant
1st Lieutenant
 
Posts: 275
Joined: Mon Jan 14, 2008 10:30 pm
Location: arse end of nowhere
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Thu Jan 20, 2011 8:41 am

When you say "won't work", what do you mean exactly?

Does the safety valve "pop" but the QEV doesn't actuate?

Does the safety valve just "hiss"?

Does it leak out of the outlet port?

How exactly are you feeding air (pilot side/chamber side), at what rate, and what is the feed pressure vs pop-off pressure?

A photo of your setup would be most helpful.

If for example you're feeding from the chamber side, the QEV needs to be modded to function correctly.

There are many parameters that could be off so again a more detailed description or better yet a photo or diagram of what you're doing would help us help you ;)
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: jrrdw » Thu Jan 20, 2011 10:00 am

I was given 2 of these valves and I can get it to work once but have to dismantel the pilot to reseat the piston before the chamber can be refilled for another shot. When I get more time to test with it I'll figure something out...
  • 0

When life gives you lemons...throw them back they suck!
User avatar
jrrdw
Donating Moderator
Donating Moderator
 
Posts: 6538
Joined: Wed Nov 16, 2005 5:11 pm
Location: Maryland
Country: United States (us)
Reputation: 25

Unread postAuthor: Cosmic Muffin » Thu Jan 20, 2011 11:03 am

Ok jack, I've been filling it from the chamber side. It's rated to 140psi and I've only taken it to about 50. When I pull the relief valve the air just hisses out of it. Not out of the port or barrel end. It seems strange that the qev doesn't have a spring.. And the seat is on the pilot side of the valve. Coul I possibly have it round the wrong way? I thought the pilot was the hole most visible in the attached picture
  • 0

User avatar
Cosmic Muffin
1st Lieutenant
1st Lieutenant
 
Posts: 275
Joined: Mon Jan 14, 2008 10:30 pm
Location: arse end of nowhere
Reputation: 0

Unread postAuthor: jhalek90 » Thu Jan 20, 2011 11:50 am

i assume you have it hooked up wrong.

also, most QEVs wont fill from the chamber side, unless you mod them.
  • 0

jackssmirkingrevenge wrote:I wonder... if you put flammable vapours inside a lady... could you get her to diesel?

POLAND_SPUD wrote:Anything is possible with the proper 3-way valve.
User avatar
jhalek90
Lieutenant Colonel
Lieutenant Colonel
 
Posts: 498
Joined: Fri Aug 14, 2009 5:37 pm
Reputation: 0

Unread postAuthor: Gun Freak » Thu Jan 20, 2011 6:25 pm

First of all why didn't you just buy a bushing for the pilot...
  • 0

OG Anti-Hybrid
One man's trash is a true Spudder's treasure!
Golf Ball Cannon "Superna"M16 BBMGPengunHammer Valve Airsoft SniperHigh Pressure .22 Coax
Holy Shat!
User avatar
Gun Freak
Lieutenant General
Lieutenant General
 
Posts: 4969
Joined: Mon Jan 25, 2010 4:38 pm
Location: Florida
Country: United States (us)
Reputation: 11

Unread postAuthor: POLAND_SPUD » Thu Jan 20, 2011 6:47 pm

Gun Freak has just nailed it

epoxy might be useful but in many cases the process looks more like:

one part + second part + epoxy = something that doesn't work and is permanently bonded together
  • 0

Children are the future

unless we stop them now
User avatar
POLAND_SPUD
Chief of Staff
Chief of Staff
 
Posts: 5405
Joined: Sat Oct 13, 2007 4:43 pm
Country: Israel (il)
Reputation: 10

Sponsored

Sponsor
 


Unread postAuthor: jackssmirkingrevenge » Fri Jan 21, 2011 12:09 am

POLAND_SPUD wrote:one part + second part + epoxy = something that doesn't work and is permanently bonded together


Used to be more often than not the story of my early development, but not necessarily the culprit in this case, especially if he's filling from the chamber side of an unmodded QEV or has got the porting wrong.

Have a look at the attached diagram, have you got the ports right?
  • 0

Attachments
images.jpg
images.jpg (10.91 KiB) Viewed 1738 times
User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: Gippeto » Fri Jan 21, 2011 1:53 am

Try filling from the pilot. Should work.

Can mod for chamber side filling by adding a spring, and tiny eq hole IIRC???
  • 0

"It could be that the purpose of your life is to serve as a warning to others" – unknown

Liberalism is a mental disorder, reality is it's cure.
User avatar
Gippeto
Donating Member
Donating Member
 
Posts: 2393
Joined: Sat Jan 19, 2008 10:14 am
Location: The Great White North...Canada eh!
Reputation: 11

Unread postAuthor: jackssmirkingrevenge » Fri Jan 21, 2011 1:56 am

Gippeto wrote:Can mod for chamber side filling by adding a spring, and tiny eq hole IIRC???


What would Brian Boitano do
If he was here right now,
He'd make a plan
And he'd follow through,
That's what Brian Boitano'd do.
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: Cosmic Muffin » Fri Jan 21, 2011 4:16 am

Yeh I didn't buy a budging cos I knew I'd never find them, and I'm an Australian, I improvise . Even if I did mess up the epoxy Job it's still fixable. And I've been trying to pilot it from the R jack, just realized it's probably P that's "pilot" and the reason it won't wok when it's the other way round is because I'm not filling from the pilot. Would I be right?
  • 0

User avatar
Cosmic Muffin
1st Lieutenant
1st Lieutenant
 
Posts: 275
Joined: Mon Jan 14, 2008 10:30 pm
Location: arse end of nowhere
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Fri Jan 21, 2011 5:03 am

Cosmic Muffin wrote:it's probably P that's "pilot" and the reason it won't work when it's the other way round is because I'm not filling from the pilot. Would I be right?


P is your pilot, A is your chamber and R is your barrel - if that's not the way it's hooked up, it's not going to work.
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: Cosmic Muffin » Sat Jan 22, 2011 12:31 am

Problem solved ;) you blokes can expect a mean bolt action smoothbore within the next few days :wink:
  • 0

User avatar
Cosmic Muffin
1st Lieutenant
1st Lieutenant
 
Posts: 275
Joined: Mon Jan 14, 2008 10:30 pm
Location: arse end of nowhere
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Sat Jan 22, 2011 12:40 am

Good to hear :) so it was hooked up the wrong way round?

bolt action


Ah, thought the pop-off meant it would be full auto :roll:
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: Zeus » Sat Jan 22, 2011 4:33 am

3/8 to 1/4 inch bushings are common as muck here, go to an irrigation store, I can get fittings from 1/8 to 4 inch sch 40 steel.

Hell, home hardware sell them, it's a bigger outlet though.
  • 0

/sarcasm, /hyperbole
User avatar
Zeus
Major General
Major General
 
Posts: 1422
Joined: Tue Oct 27, 2009 7:34 pm
Location: 'Straya, C*nt
Reputation: 2

Next

Return to Pneumatic Cannon Discussion

Who is online

Registered users: Bing [Bot], Google [Bot], Yahoo [Bot]

Reputation System ©'