Suggest an air valve for homemade marker (spyder, autococker, etc)

[trains are bad]

I'm designing my own airgun based on paintball parts, and I need a valve. I see no reason not to use a paintball valve; I want it to take 1000PSI and be able to handle CO2. It would be simple to use a valve that slides in and is anchored with a setscrew, like a Spyder valve, but Spyder valves leak gas back for blowback operation and I don't want that. I could use an autococker valve but machining threads for the lock screw into the body would be too hard. Can I anchor an Autococker valve with a setscrew from the bottom like a Spyder? Is there another type of valve? What do other non-blowback markers like Angels and whatnot use for valves?

By the way, why is it so dead here? I remember this place being really active.

[Newt]

In either case, it's probably going to have to be a poppet valve. Existing spools and noids don't generally see 1000 psi coming through them.

You could certainly use a spyder valve. Just seal off the blowback side if that's what your application requires. There are a number of ways to do this. Most involve getting creative with JBWeld or drilling out and tapping the hole for a pipe thread.

[trains are bad]

I've gathered that the Trilogy 'cocker valves are a non-blowback design but are held in with a setscrew like a Spyder valve. I don't think they are 100% sealed with an oring, but at least they won't have deliberate blowback.

Now, however, I'm worried that a 'cocker valve will be too hard to open. If the valve seat is .375 inches in diameter then at high pressures the valve will be held shut by like 80 pounds of force, even disregarding the valve spring. That might be too much to open with a pneumatic ram unless I use a big heavy bolt for momentum a la cocker. High cycle rate is very important to me.

I remember reading way back about Impulse valves and how they supposedly had some poppet-valve design but with a pressure-balanced design so that they remain easy to open even at high pressures. I guess other ram-driven electro markers use similar air-biased valves, but I'm having a hard time finding out what these valves look like, how they are held in the marker, and most importantly where I can buy one.

[sjrtk]

It sounds like you want a ram driven poppet valve airgun to fire at a high rate take 1000 psi (some times or all the time?) and be CO2 compatable. With out regulating the pressure down to the valve you are going to need a big ram to hammer the valve open. Probably why cockers use a hammer and not a ram. You are asking alot but this is the info I have.

Cocker valves are held by a set screw and jamb nut (the hard one to tap threads for), and spyder valves are (for the most part) a copy of a cocker valve but smaller and blow back but similar design. If a spyder could hold up to unregulated CO2 pressure and function with only a set screw, I see no reason why a cocker valve couldn't as well just use a metal one I.E. plamer valves not the stock late model plastic type. I belive that up to 97 autocockers were sprung for unregulated CO2, please correct me if i am wrong. So it is possible for them to opperate with the nearly 80 psi (your number i don't know for sure) acting in the valve head with the proper spring pressures on both sides of the valve.

[trains are bad]

It sounds like you want a ram driven poppet valve airgun to fire at a high rate take 1000 psi (some times or all the time?)

I simply want the highest velocity and the highest cycle rate possible. Since this will be a small-caliber gun, I am guessing that my velocity will be pressure-limited rather than flow-limited. The highest pressure I can get is 1000psi HPA or raw CO2 (until shootdown occurs).

I believe that up to 97 autocockers were sprung for unregulated CO2, please correct me if i am wrong. So it is possible for them to operate with the nearly 80 psi (your number i don't know for sure) acting in the valve head with the proper spring pressures on both sides of the valve.

I didn't say 80psi, I calculated that at 1000psi the valve is shut with 80 pounds of force. But the calculation doesn't really matter; it is a proven fact that autocockers and spyders can open valves at raw-CO2-pressures, but they use heavy spring-driven hammers and not pneumatic rams.

With out regulating the pressure down to the valve you are going to need a big ram to hammer the valve open. Probably why cockers use a hammer and not a ram.

This is the crux of my problem. I want very high cycle rate and I know that electropneumatic markers can cycle at ~20cps but they are usually low-pressure designs running on 2-300psi, correct me if I'm wrong. I don't know if those markers' electropneumatic rams would be able to hammer open a poppet valve at 1000PSI at all, let alone at the same cycle rate. I have established that a cocker valve will physically fit, but now I'm not sure if it will work, and I'm looking for a poppet-type valve that remains easier to actuate at high pressures. It's certainly possible to make such a valve, and I could make one if I really had to, but I heard that such valve designs exist, at least I heard the impulse air-biased valve thing claimed a long time ago, but I do not know about such valves, I only have experience with mags, cockers, and spyders.

[factoid]

What type of caliber are you looking at? What kind of velocity are you trying to get from what mass of projectile?

I don't think it necessarily follows that you MUST have 1000psi to achieve high velocity on a small caliber object.

Nailguns run at 100-120psi and based on what I can find have muzzle velocities that range from 100 to 250 fps depending on the type of nail and the type of gun.

[redlaser666]

Since you have not been very specifice about your proyect I will just give some general sugestions.

1. If you use an autococker valve, you can improve the response by using a light spring.

2. LCD/ LED Angels operated around 550 psi and are elecropneumatic. They use a ram connected to a brass hammer to impart enough force to open the valve. They are capable of 20 bps ROF.
You may even be able to adapt one to use in your proyect. (PM me if you need one, I have an extra one)

3. You can use an LPR to regulate the driving force of the ram (say 80 - 90 psi)and still have the main valve operate at full pressure.

4. If you want to have a high cycle rate AND be electropneumatic you will want to stay away from CO2 since it will damage the delicate internals of a solenoid.

5. Depending on the caliber and weight of your intended proyectile and the length of the barrel you may only need a very short dwell at high pressure, or you could use a lower pressure and increase the dwell (how long the ram keeps the valve open)

[trains are bad]

I haven't decided on the caliber yet but it will probably be .22 or .177. .22 will be easier to build but .177 has the advantage that it will use BBs. I need 600RPM or it's not even worth building. I won't be happy unless I can get at least 1200RPM.

1. If you use an autococker valve, you can improve the response by using a light spring.

I would definitely use the lightest spring that I could as long as it was able to reset the valve quickly enough.

LCD/ LED Angels operated around 550 psi and are elecropneumatic. They use a ram connected to a brass hammer to impart enough force to open the valve. They are capable of 20 bps ROF.

That's good to know. Do you know anything about angel valves? The diameter of the valve seat determines how hard it is to push open. I would rather use as light of a hammer as possible to reduce shake and recoil. Since I feel that operating pressure will win out over flow in this case, I may have to make a custom valve with a smaller diameter valve seat, or design my own air-balanced valve.

You can use an LPR to regulate the driving force of the ram (say 80 - 90 psi)and still have the main valve operate at full pressure.

Of course. I thought all electropneumatic markers had LPRs. Good point about the CO2. In my experience solenoids don't do too bad on CO2 if they are behind a Micro Rock but I don't exactly shoot paintballs at sustained 20bps.

Depending on the caliber and weight of your intended projectile and the length of the barrel you may only need a very short dwell at high pressure, or you could use a lower pressure and increase the dwell (how long the ram keeps the valve open)

There would never be an advantage of using lower pressure and longer dwell for me. I would be using higher pressure AND higher dwell. The only thing that matters to me is ROF and maximum velocity, so I will set dwell by increasing it until it stops increasing velocity, and then increasing it slightly more to be sure I'm getting as much velocity as I can. And I will simply increase my pressure to as high as I can and still have my pneumatic ram open the valve. Since my projectile is small and my barrel fairly short (12") I think that I'm going to want as high a pressure as I can get. I have no idea what pressure spring-piston air guns generate, but it might be a good deal more than 1000PSI.

[redlaser666]

I haven't decided on the caliber yet but it will probably be .22 or .177. .22 will be easier to build but .177 has the advantage that it will use BBs. I need 600RPM or it's not even worth building. I won't be happy unless I can get at least 1200RPM.

Now that you mention caliber I can see where you are trying to go.

Angel valves are of a similar design as cocker ones, they are held in place by a pin and would probably work just as well. Depending on your budget and machining capabilities you could get an old Angel and modify the top breach to fire your projectiles.

[trains are bad]

The gun, if I ever am able to build it, will have to be made from scratch, because I want it to be bottom-feeding. So, since I will be doing so much machining and fabrication, it's really not that much more work to make my own valve. I just wanted to use a paintball valve so I would have a source of valve seats and orings. Making an air-balanced valve would be simple. You could use a cocker valve body, and then make or modify a valve seat with a pin that projects forward into a bore which is vented to the atmosphere. Depending on the relative diameters of this bore and the valve seat, you could make it arbitrarily easy to open at any pressure, even make it perfectly balanced so that the valve spring was the only force holding it shut. It would introduce another leak point and some friction though.

[redlaser666]

So by bottom feeding I am assuming you want it to be magazine fed???

I am not familiar with the balanced valve system, but If you were to build it from scratch then it would definitively be best that you make your own. Then You may be able to use the valve seal from almost any paintball marker.

[trains are bad]

This was my idea for an air balanced valve. Black is marker body, silver thing is the valve body, grey thing is the valve seat, and blue is HPA, and brown is the hammer. You could use a cocker valve body if you wanted to, and modify the valve stem.

[redlaser666]

Looks like a good design. If you make it almost perfectly balanced you can use a vely light sring to ensure it seals when first aired up as well.

Also sice you are using a very small caliber the valve and the ram dont have to be as large as a paintball ones. Instead of 0.75 in stroke or so for a ram you can use one that has maybe 0.25 in travel and also about a third in diameter. A balanced valve like the one you drew would be very easy to open so the ram doesnt have to be as powerful.

Here is a design that may fit what you are trying to build:


Pardon the crapy paint job.

black = gun body
red = valve stem
gray = valve
yellow = ram and hammer
blue = link pin
pink = bolt


Also the ram could be spring loaded so you only need air for the forward stroke, like a FASOR

[trains are bad]

I considered a FASOR ram but as far as I know double-acting rams are faster and smoother.

I'm debating whether to make the ram integrated into the body, or to literally just encase a double-acting Clippard minimatic ram into the body and plumb lines to it.