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Solenoid as semi auto?

Posted: Thu Aug 01, 2013 11:17 am
by eliechahine
Hello

I've been wanting to build a reliable and accurate semi automatic air gun.

I already have a QEV, but i think i got a better idea.

I did some research on the daystate air wolf gun which costs about $2.3k

And i wanted to replicate its mechanism.

As far as i know it can be home built, any oppinions on the matter?

(PS:check this video, i will be working on this basis )

Thanks!

Posted: Thu Aug 01, 2013 12:06 pm
by jackssmirkingrevenge
I just sold my Mk.3, was genuinely upset to see it go as it was an awesome gun to shoot - no vibration and valve noise associated with conventional pneumatics, very quite and dead accurate.

Using a solenoid valve to fire directly with a momentary switch could have its merits.

I recently bought one of these that could fit the bill: http://www.ebay.com/itm/Heavy-Duty-12V- ... 5af285765d

Haven't had the time to try it out yet.

edit: just did, useless. as it's meant for air horns, it just vibrates like a... well, something that you'd find in your wife's bedside drawer.

Posted: Thu Aug 01, 2013 1:05 pm
by eliechahine
Haha, nice one.

I'll try different brands of solenoids, but what i'm worried about is how to make that solenoid go off and not keep going even if i press the trigger, because i don't want it to go full auto.so the timer or as you called it momentary switch.

And the second thing which valve is used to attach the solenoid to the barrel in the daystate so i can get one of my own.

Or any other valve that will do the trick.

Posted: Thu Aug 01, 2013 1:42 pm
by jackssmirkingrevenge

Posted: Thu Aug 01, 2013 2:01 pm
by eliechahine
Yes i got the basic idea of it, i just don't know where i can get this kind of valve that i need to complete my project (blue square on my attached picture)

I don't know it's name, or if any other valve that functions in the same way would be good with me.

Sorry for the troubles.

Oh and if you're wondering where i got this picture from it's from the video in my first post.Image

Posted: Thu Aug 01, 2013 2:19 pm
by jackssmirkingrevenge
You can chop up a hammer valve. Wyz shows you how here: http://www.spudfiles.com/forums/hammer- ... 23202.html

Posted: Thu Aug 01, 2013 3:10 pm
by eliechahine
A thought just came by my mind.

What do you think of the valve located at the top of a standard fire extinguisher? looks rather similar to the one in the picture

Posted: Thu Aug 01, 2013 3:15 pm
by Gun Freak
You will need a really strong solenoid...

Posted: Thu Aug 01, 2013 3:25 pm
by eliechahine
I just took a few pictures of the fire extinguisher valve.

If the solenoid doesn't do the job, i can replace the spring in the fire extinguisher valve by a weaker one..i think. :roll: not sure if i can.

Image
Image
Image

Posted: Thu Aug 01, 2013 3:34 pm
by wyz2285
I've tried this before... God knows how many times...
I'm pretty sure with any "ebay" solenoid it won't work, the only time I got it work with a well made hammer valve was using a big fat 6v solenoid driven by a 100v cap, literally use a coilgun to actuate a hammer valve. I know there are 12v electric nailguns that can punch a nail in to wood using a solenoid, but I suppose it would be a BIG solenoid.
However, at low pressure, powerful shots can be achieved by combining a hammer valve piloted piston valve.
If you don't replace the spring, try to open it with a solenoid would be like throwing a egg to a concrete wall :lol:

Posted: Thu Aug 01, 2013 3:47 pm
by eliechahine
Hey wyz i'm a big fan of your youtube videos.

Well you're right i'm going to have to replace the spring because i can't even close the valve with my bare hands without the black leaver.

I'm not sure if it's replaceable though what do you think?

Posted: Thu Aug 01, 2013 4:00 pm
by wyz2285
I'm not sure if it's replaceable though what do you think?
It is replaceable, I took out a spring from a fire extinguisher and I'm using that spring on my paintball regulator... You can tell how strong it is from that :roll:
With a weak spring or even no spring at all, I doubt it would work with pressure inside the bottle, the pressure also pushes the valve stem to keep it closed, larger the diameter of the output port, harder it is to open it and as I remember, the port on a fire extinguisher wasn't small.

Posted: Thu Aug 01, 2013 4:04 pm
by eliechahine
so what do you suggest i do with that fire extinguisher valve?

I don't have that much supplies to build/machine my own stuff i can salvage alot of things, and modify stuff.

Thanks for the help so far

Posted: Thu Aug 01, 2013 4:09 pm
by wyz2285
Remove the valve, let me take a look.
I best guess for now would be epoxy a smaller diameter tube inside the original port to create a smaller sealing surface.

Posted: Thu Aug 01, 2013 4:12 pm
by eliechahine
it's 12 in the morning where i live so can't do much without waking everyone

, i will try and take it apart tomorrow morning first thing and post a pic here.

Thanks again!