Triggered burst disk

[mikemurph]

I have been searching the wiki for new ways to trigger my pneumatics. I saw this on the wiki:
http://www.spudfiles.com/spud_wiki/inde ... burst_disk
the pressurization between the two burst disks is the most interesting way to me, but i have two questions about this method. one, what kind of pressures are we talking about, I was thinking about half of the pressure it takes to burst the disks. two, does this method work with any kind of burst disk, mine are foil.
I would really like some help on this one so give me some feedback.
P.s. right now i have a single burst disk method with a 3/4" barrel, and 1 1/2" chamber

[dudeman508]

http://www.spudfiles.com/forums/burst-d ... 17002.html Mine worked.

[GalFisk]

Dudeman: Your link has a period at the end which breaks it.
Mike: The pressure between the burst disks should be about half the chamber pressure, and it needs to be more than half the burst pressure of the burst disks (about 70-80% of the burst pressure should be both safe and reliable). As long as these two criteria are met, it will work with any kind of burst disk.
Follow dudemans link (remove the period at the end of the url) for one working example, in that thread there's a link to another working example. Good luck with your build

[mikemurph]

Thanks dudeman, my burst disk related searches brought up alot of hybrids, and Im glad you have used this system successfully.
and thanks GalFisk for the in depth info, and for fixing dudemans link.
I Have one more question:
Is this system a whole lot more effective than a simple ball valve about a foot before the actual burst disk. This way seems simpler and quicker beacause there is no extra fiddling with two burst disks.

[mikemurph]

can anybody answer, or is this just open waters?

[rp181]

My triggered burst disc uses one union, with a angled hole drilled through. A sharp nail is poked, and it fires. I recently outfitted it with a solenoid, which stabs the membrane, and allows remote control.

[mikemurph]

where do you put your solenoid, I have thought about that, but cant think of proper placement

[c11man]

mike, are you thinking of a solenoid of a sprinkler beceause rp is talking about the kind that can pus or pull on a pin/rod

[mikemurph]

no im thinking push pull, just where would i put it on the cannon?

[c11man]

oh ic, put in on the barrel side of the union

[mikemurph]

I have a 3/4 inch barrel which doesn't leave room for much

[rp181]

It is in the union footprint. I emailed you pics.

[mikemurph]

Thanks rp181, that is really helpful, do you think radioshack would carry those?
And what is the exact name of the one you used + where you got it

[THUNDERLORD]

Cool link.
In theory, it should work with any spud range of pressure.
It will require a lot of testing to figure your burst layers and bursting pressures.
I'd stick close with the reference info page.

Seems like a shrader valve might be a bad choice for the trigger, A presta bike valve would probably be safer (?). 8)

BTW, a sharp point on the back of ammo OR barrel could burst a single disk...but then it needs a trigger mech. to release it.

[mikemurph]

So in your opinions triggering it the way i originally stated is the easiest way to do it, but i still want to know about the ballvalve before the burst disk
=====[O]=======( l )=====
burst disk ball valve chamber=>
<=barrel

BTW, a sharp point on the back of ammo OR barrel could burst a single disk...but then it needs a trigger mech. to release it.

I would do this for a mortar type weapon, but i only have a 3/4 inch barrel

Seems like a shrader valve might be a bad choice for the trigger, A presta bike valve would probably be safer (?).

Whats a presta bike valve?[/quote]