Pneumatic Pen-gun Project

[jackssmirkingrevenge]

But Im being honest my gf and I are kinda yeah into that.

Lol really now? proper S&M or just tied-to-the-bed-with-cheap-novelty-handcuffs-and-tickled-with-a-feather sort of stuff? Been 4 years since I had a proper relationship of that sort, still have the scars

[A-98]

err....right...uhhh.....off topic anyone? quick, start a topic "weird fringe relationships i have had"!

um....[insert way to get back to subject]

[jackssmirkingrevenge]

The pain, it makes you feel alive

*ahem*

Yeah, er.. pneumatic pistons and whatnot

[A-98]

would be an EDIT:

16 man and loving it.

heh, i thought i saw a vid of you around here, and you were like...squeaks. maybe im crazy. or maybe i was at the time

[joannaardway]

I often ended up electrocuting myself with the poor wiring

Its impossible to electrocute yourself more than once, because 'electrocution' means death by electric shock

Yup, and I've managed it several times.

Dying isn't comfortable, but the Devil's absolutely terrified of me, and God won't let me in, so they just have to keep on letting me come back to life. Quite useful really.
Disclaimer: It works for me. I cannot confirm that you will get the same arrangement.

@JSR: I'm always rather surprised that you can successfully trigger a piston valve with the tiny flow of a schrader. I could understand it for on this small, but did you not also do it for your larger marble cannons and stuff?

I understand your pistons are carefully cast, but the equilisation must be fairly slow...

[jackssmirkingrevenge]

@JSR: I'm always rather surprised that you can successfully trigger a piston valve with the tiny flow of a schrader. I could understand it for on this small, but did you not also do it for your larger marble cannons and stuff?

I understand your pistons are carefully cast, but the equilisation must be fairly slow...

Ignoring this case, the pistons are cast inside the tube that they will eventually be mounted in, meaning the fit is extremely snug. Still, equalisation is fairly instant, though I always charge for a few seconds extra to make sure the chamber is up to maximum pressure. Also note that I'm always careful to leave the bare minimum of pilot volume behind the piston - 1/4th of the calibre - meaning that the pilot volume is as tiny as it can be. In this case for example, the space between the back of the piston when closed and the end of the chamber is a mere 5 millimetres, meaning a 1" diamter piston can be easily triggered with a schrader. My motto has always been efficiency over everything, which leads to quite a few clashes with our more permissive friends across the pond

[al-xg]

Hi every one,
I made a very similar design just a little bigger really, 14mm OD and 6mmm ID barrel the whole thing is 14cm long. The pilot valve is the schrader (it was going to be a 16mm OD section of pipe blocking holes in the chamber behind the piston, like a slide valve... but i couldn't get it airtight...)
The piston is a small bit of two component glue paste thing with a rubber disk to seal the barrel. There are no equalisation holes and i used the same pipe as the chamber to cast it.

My first plan was to make a James Bond like pen that would fire the nib... but id like to shoot someone one day so i went for something less dangerous.

However, I have some technical problems (first one was a leak around the schrader...) I'm not sure the piston moves back and i also loose alot of air when disconecting the pump wich seems to trigger it until there isnt enough pressure anymore... the pilot volume is 0.565cm3.

This my first atempt at firing a coaxial, do you have any suggestions ?

[al-xg]

@Joannaardway: One of my french friends just has a schradder valve on the pilot port of a 3/4" QEV and although it sometimes farts( well that noise made by the piston vibrating back and forward) it usualy works fine.
Although over 180psi it can trigger when he removes the pump...

[al-xg]

d*mn, can someone help me out?
I wanted to edit not triple post !

sorry

[A-98]

ya, this is a cannon submission, so editing is off. no harm done.

[iknowmy3tables]

uhm I'd like to add something else I see... jack is your new profile pic a sketch of the Virgina Tech shooter? its just that he's using a pistol, is pissed off at society based on his shirt, and he looks like a young Asian male
if it is I just think it might be questionable

[jackssmirkingrevenge]

Er, that's a charicature of me

Ok, changed to a less militant version

[TwitchTheAussie]

Lol he is the guy he just held the other dude at gunpoint to do it all and then he shot him. No just kidding no insult intended.

[A-98]

ya, i was wondering that myself. ah well, i made a nasty joke about it all myself.

[iknowmy3tables]

OH OH crap sorry I had no idea its just that you know he's like angry and it looks like some sketchy political cartoon...
and I should have known the beard isn't on the VT shooter, please don't shoot me.....

so uhm I've been still trying to make a diaphram acuated by a shrader but the diaphramkeeps geting sucked into the barrel , man I suck at diaphrams, I suck at O-rings I am a crappy spudder, or valve maker