Trigger Mechanism, will it work?

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Sat Jun 14, 2014 4:45 pm

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overview of the main setup
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how effective is this setup going to be eg: holding pressurized air,
maximum psi 700-800.
I think leakage can be avoided by using heavy duty rubber seals, let me know if you guys think this mech will work?
fenrir
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Sat Jun 14, 2014 7:33 pm

Sure it will work. I think someone on the airgun forums suggested the same setup. Make sure your chamber can withstand the pressure. Why not use a regular hammer valve or qev though?
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bravootome
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Sun Jun 15, 2014 12:18 am

Is your design meant to be a QDV ? Cuz i dond see how you will seal the air chamber/..700 psi will blow that up.. unless it is a QEV or a QDV or you got a O-ring on your piston and the sea; is against the walls of that pipe......
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Sun Jun 15, 2014 11:09 am

fenrir wrote:Why not use a regular hammer valve or qev though?
I think it would be really had to construct a hammer valve like the Crosman 1322 etc and i don't understand how QEV works never made an effort to even try understanding it and applying in any of the designs I ever thought of
bravootome wrote:Is your design meant to be a QDV ? Cuz i dond see how you will seal the air chamber/..700 psi will blow that up.. unless it is a QEV or a QDV or you got a O-ring on your piston and the sea; is against the walls of that pipe......
I looked for some QDV pics on google its kinda like a QDV ,I don't know if this mechanism is related to some thing i totally made this up myself because with this mech its easier to put all the parts in a wooden body and make it look like an l96 rifle.
blow up which part?

this part?
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bravootome
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Sun Jun 15, 2014 12:56 pm

A QEV is far better, and allows you to multiple shoots..... i find it superior of hammer valves..

What make your rubber seal to stay there and seal the air chamber when you put 700 Psi inside the tank ? that bolt wont do it if only apply an equal oposite force...witch i dont see how you will do it.... As i said a piston with o-ring, should hold on.[youtube][/youtube]
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poor drawing skills on ms paint, I think now you'll understand.
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RedAsh
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Wed Jun 18, 2014 11:44 pm

It should theoretically work if you can get a good seal but that bolt is going to be a missile and it is aiming right at you so if it brakes free you are going to have big problems. Fined out how a QEV works they are cheap and a much better solution, if you don't want to go down that road I suggest making a coaxial gun instead. That being said it is always the new things that no one thinks will work that end up being the best inventions.
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Fri Jun 20, 2014 10:52 am

I'll put the whole trigger mech part in a steel case so the bolt won't be a problem.
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cammyd32
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Sat Jun 21, 2014 6:39 am

That set up is probably not going to work very effectively, if at all.

For starters the trigger would have to be applying an active force against the piston for it to seal correctly which would defy the whole concept you have going of an unbalanced valve,
And secondly you would have to have literally nanometers of play in the trigger mechanism to avoid a steady leak.

If you are really keen on this set up you would need to bolt to be in spool, as opposed to a face seal, which would eradicate the need for microscopic tolerances, but unless you have a lathe handy this is going to be nigh on impossible to do.
I would seriously consider the set up suggested by bravootome, along with having potentially better power you could easily and cheaply fabricate it from off the shelf parts,
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jackssmirkingrevenge
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Sat Jun 21, 2014 9:47 am

hectmarr wrote:You have to make many weapons, because this field is long and short life
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cammyd32
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Sat Jun 21, 2014 11:08 am

Have a look: pneumatic-cannon-database/topic7457.html
I did remember your design Jack, but for starters you were only using 100 psi, on a small sealing face,as opposed to the 700 proposed in this design.

Also another thing is that your design used a flexible rubber seal and a trigger block which could be considered to be applying pressure to the rear of the seal in a similar way that a wedge would, which gave a bit more room for larger tolerances, also, the pivot for your trigger was nearly directly in the line of travel for the piston, which reduced to natural tendency for the trigger to rotate out of the way, and therefore preventing the valve from leaking.

As proposed here the design would have to be very certainly machined with a high level of precision, and certainly would be extremely subject to wear, It's not exactly a pneub friendly project, especially in comparison to something like a QEV or hammer valve based design.
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jackssmirkingrevenge
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Sat Jun 21, 2014 1:38 pm

Fo sho, that was built when I was 17 - these days it would definitely be a machined QDV :D
hectmarr wrote:You have to make many weapons, because this field is long and short life
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POLAND_SPUD
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Sat Jun 21, 2014 2:47 pm

Hmm Jsr

Rebuild it and add a bolt action type mechanism for loading. To ensure fast opening times make the valve & bolt handle two seperate parts that are either spring loaded or can move independently a little bit

Personally I'd add an inbuilt pump for it - to make it self contained. Might be a cool project now that you have access to and all
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Tue Jun 24, 2014 7:59 am

POLAND_SPUD wrote:Might be a cool project now that you have access to and all
I currently have less access due to the location of my tools, though I do really need to push myself to make some personal projects.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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dart guy
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Mon Jul 21, 2014 1:38 pm

Your idea seems that it would work, but a good question is how long is your reload going to take. If the design is somewhat to scale I think it would take forever to re load as well as be bulky and not fit correctly inside of a l96. I designed a qev set up for a l96, but it is a cartrige fed idea and is only half finished on spud files. I designed the rest on a notebook after basing an idea off of a bolt .22 rifle. One last question, how will you load it? Will it be a breech load or a muzzle load?
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