Side-actuated release valve

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Bando_Red
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Mon Nov 04, 2013 10:05 pm

my regular computer died and this one has trouble viewing a lot of the attachments here. I tried to avoid flat out asking "how do I do this" kinda questions but valves seem the be one thing I can't wrap my head around and It doesn't help that I'm a hands on learner. What is the best way to actuate a valve from the side? I'm trying to make a flint/caplock system that looks like a real caplock firearm and figured if I put the release valve in the "nipple" and have it activated by the impact of the hammer then it should work fine. This would mean that the air flows in at a 90 degree sideways angle, but I don't think that really effects things. My expertise is primarily is firearms so a lot of the valves and air stuff is new to me. Alternatively the release valve could be directly behind the breech and still activated by hammer impact, but that would require linking the impact area to behind the breech as well as redirecting the airflow.

Additionally, pulling back the hammer opens a trapdoor from the tube magazine to feed the bbs into the breech where they'll be held in place by a magnet, but I'm less concerned about that as I've more or less worked out the system. Its a "manual repeater" in this way. The air storage (either C02 powerlets or PCP, or both alternatively) is stored in the butt of the pistol. I may make a few variants of this basic design, a smaller "coat" pistol powered just by powerlets and more compact, interchangable barrel/magazines for larger sizes.
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cammyd32
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Tue Nov 05, 2013 3:43 am

At higher pressures such as the 800-900psi that unregged co2 would supply, it would not effect the performance of the gun a great deal if you had a 90 bend in the line, although it's not ideal.
What kind of launcher and layout were you thinking of? I know what you mean by the style of body you will be mounting it in, but without any more information I'm trying hard to envision what you are attempting to to, I can't make heads or tails as to whether it will be a coaxial or a hammer valve repeater.

Depending on what you are doing, there are quite a few store bought valves which have a valve stem already protruding from the side, alternately, if you have access to machine tools you could make your own,
BTB has made a few brilliant looking hammer valve repeaters that might be of some interest, have a look here
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jackssmirkingrevenge
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Tue Nov 05, 2013 5:10 am

Image
Muff CO2
The .25 cal barrel unscrews for breech loading. A 12 gram CO2 and valve
are housed in the in a shortened section of a Crosman 150 tube.
Image
Flint Pump
The .22 cal brass barrel that is unscrewed for breech loading.
The center mounted hammer with steel flint strike the frisson to
open the Crosman 760 valve.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Brian the brain
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Tue Nov 05, 2013 12:09 pm

Image

My latest build.


A coaxial valve actuated by a hammervalve on an elbow.
Flintlock style.

Coaxial means that gas is stored in a reservoir around the barrel.
A piston seals the back, releasing pressure behind that piston causes it to pop back.

This basic design means it has to be muzzle loaded, wich fits the theme perfectly.

I'm working on several idea's, a breechloaded coaxial being one of them.
As you are just starting out I suggest you try a coaxial- hammervalve combo as it is about as basic as it can get, compact and very powerful.
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Oh my friggin god stop being so awesome, that thing is pure kick ass. Most innovative and creative pneumatic that the files have ever come by!

Can't ask for a better compliment!!
Bando_Red
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Tue Nov 05, 2013 2:06 pm

I'll see if I can get the scanner working and upload a sketch later today. It is designed to be a repeater cammy, a "hammervalve" if I have my terminology correct. its not a coaxial however because the reservoir is in the butt of the gun.

flintlock looking
magazine-fed
flush package IE minimal external doodads
target-practice and plinking
fire small caliber round balls or BBs.
Get at least 30 shots per fill or powerlet

the tank is stored in the butt of the pistol.air flows from there to "side mounted" hammer valve. (direct flow from reservoir inefficient?).The actual barrel and magazine assembly are housed within a false barrel to keep up the appearance of a large caliber muzzleloader. A tubular magazine under or over the barrel holds .177 bbs. cocking the hammer back will open the breech and allow a bb to chamber. Not sure whether to make it a sliding breech or a falling block sorta setup and whether it will close upon dropping the hammer or before the hammer is fully cocked. It'll be a matter of what's easiest. For simplicity sake I was going to go with a gravity feed and have the bb simply roll into the chamber with the angle the pistol tilts to when adjusting your grip to cock the hammer, but a spring loaded magazine wouldn't be much more complicated. The hammer strikes the nipple or valve on the lockplate assembly to release the air sideways into the breech Either way, simply cocking the hammer and pulling the trigger would chamber a round and fire it until it runs empty on air or ammo.

BTR, I like that hammer setup on yours. I saw the earlier posts but not the later ones. I was also looking at that very site where those pics came from last night Jack, but I just couldn't visualize how it was working on the inside.
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Brian the brain
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Wed Nov 06, 2013 1:14 pm

What you are describing is basically a Girandoni airgun.....

Google "girandoni" and you'll see...




The coax design uses two valves: one main valve and one to actuate it.

I used a hammer valve ( poppet valve) to pilot the main valve.
Using a hammervalve as your firing valve would work well for small diameter bb's and save air at the same time, so for what you are planning it should suffice.
Gun Freak wrote:
Oh my friggin god stop being so awesome, that thing is pure kick ass. Most innovative and creative pneumatic that the files have ever come by!

Can't ask for a better compliment!!
Bando_Red
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Fri Nov 08, 2013 12:01 am

never thought about how many similarities it acually has to the giradoni system. I mean obviously I've looked at it for inspiration but I guess I didn't realize the similarities. Obviously mine isn't quite as sophisticated or polished. turn the barrel 45 degrees and its basically my design except the magazine pivots into place via thumb. I guess I just need to construct a trigger assembly with a bb carrier to load each one. I'll update when i make more progess
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Gun Freak
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Fri Nov 08, 2013 11:13 pm

Just something to think about- I don't know what style blowguns you have access to, but the inline design with the lever-style hammer (not the pistol grip) can be easily converted for use on a hammer valve gun. Just secure a rotating style hammer that hits down on the stem. They have a 1/4" thread input and 1/8" thread output so it's perfect for Airsoft caliber.
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