Small QEV piloting larger QEV

[AlfiePB IanB]

As per title, would either QEV need the spring and hole modification to reset it for the next fill? Been trying to think about this, but not too sure about it all, but from what I figure mods wouldn't be necessary, someone who knows please tell me

[matti]

no need to modify them.

[Kensingt0n]

I've tried to get this working with some parts lying around but had no success unfortunately.
I'm thinking both air ports will need to be connected to the same air source and 'R' port from the 'piloting' QEV will connect to the 'P' port of the 'firing' QEV.
Although, thinking about it, and anyone please free to correct/comment, you would probably have to use a small fill area on the 'A' port of the 'piloting' QEV. 'R' port would still connect to 'P' on the 'firing' QEV. This QEV will have the main air source connected.
The 'firing' QEV would need to have the spring mod to allow you to refill the main air source easily in that configuration I'd say.

[AlfiePB IanB]

Thanks for your help, much appreciated. So for the smaller piloting QEV any pointers on which way to plumb it to the larger?

[Kensingt0n]

I've tried to get a setup like this working before but never had any success unfortunately.

Thinking about it, and anyone please feel free to correct/ comment, you could connect a fill valve to 'A' port on the smaller "pilot" QEV, the triggering valve (whatever it may be) connects to 'P' port on "pilot" QEV. 'R' port would then connect to 'P' port on the "firing" QEV, the main air tank would be connected to 'A' port on "firing" QEV and obviously then 'R' port on "firing" QEV would be the barrel connection.
If this is a possible setup, I imagine that both QEV's would need to be modded to allow for refilling in the most simple fashion.

[matti]

Here is example of how to use QEV for piloting a larger valve (qev or pistonvalve, same way):

http://www.spudfiles.com/pneumatic-cann ... 25733.html

Sooo fit in a way that the smaller QEV "chamber" is the pilot volume of the larger one. You will fill the main chamber through both QEVs using the pilot port of the small qev.
There are many cannons using a double QEV setup and they work. I have used them like that too..

[AlfiePB IanB]

Thanks guys,