Tips on creating a break-disc valve mortar.

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SP00K
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Mon Aug 03, 2009 7:17 am

I made a break-disc valve mortar a little while ago.

Actually, I took the barrel off an older cannon, and created a break-disc barrel.

Inside of the barrel, there is a wooden eyelit screw into the side of the barrel. I created a piercing mechanism that goes thru the eyelit and does not get launched out upon piercing.

So all in all, you drop a projectile down the barrel, hits the piercing mechanism, which breaks open the disc valve.

I usually get up around ninety psi with four pieces of aluminum foil.

Does anyone have any tips I should be aware of when using this kind of cannon? I'll post pics up in a few minutes of everything.
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Mon Aug 03, 2009 5:20 pm

YES!

Safety first!!!!!


Make for sure everyone and everything is out of firing line. Make for sure your ducking out of the way path is all ways clear. Don't let on lookers coax you into "aw it's OK, it wont hurt anything". Never under any circumstances look down the barrel, or let anyone else look down the barrel.

Keep ammo uniform and proper fitting. Only one operator at a time. Never go alone and all ways have a cell phone on hand, so you can call for help if you need to.

Others can fill in what I missed. IMO mortar cannons are the most dangerous to work with being as how you handling live ammo and have to duck the firing cannon. You should have a "cockabul" firing pin so you can set them ammo in then activate the firing pin remotely.

Feel free to ask any questions about what Iv'e posted :D .
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SP00K
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Tue Aug 04, 2009 1:02 pm

Thanks for taking the time to reply.

I'm a VERY cautious person when it comes to anything dangerous like this.

The firing pin is a great idea, I think I'm gonna do that later today.

Anyone else have tips on mortars?
We are all worms, but I do believe I am a glow worm.

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Hubb
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Tue Aug 04, 2009 4:04 pm

Don't got no advise, but I got a link.
http://www.spudfiles.com/forums/burst-d ... t7500.html
He build a burst disk mortar that does just what you are planning on doing, with the exception that the puncture pin is built onto the round.

I would say take a look at Gort's QCTBDC, but it just links to some stupid video website. It's not a mortar, but is one of the first triggered burst disk launchers I can think of and would have probably been good for ya. Sorry.
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SP00K
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Wed Aug 05, 2009 12:39 pm

Hey! that was helpful! Gave me a few good ideas.

I didn't want to have the ammo pierce it because I plan on using this in paintball to fire paintball grenades. (I don't think people would appreciate it if I was hurling nails and screws at them in a match). Plus I didn't want to have combustion because the local field allows homemade items but not explosive items.
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Hubb
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Wed Aug 05, 2009 12:43 pm

Well, in that case, I'll let you pick up on an idea of mine that I never got to completely work right.

Image

It is a mortar designed to fire from an electric sprinkler valve. When the round slides down, it hits the central bracket (or barrel stop :D ) and completes a circuit, which fires the solenoid in the sprinkler valve.

I got it to fire on every shot, but never put a chamber on it to finish it. You are welcome to it if you want.
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SP00K
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Wed Aug 05, 2009 1:02 pm

That's awesome, I will most definitely try it out.

Wouldn't you have to have a car battery or some large power source to get the sprinkler valve to open up quickly if it's electric?
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Hubb
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Wed Aug 05, 2009 2:40 pm

2 9volts work.
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Technician1002
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Wed Aug 05, 2009 4:10 pm

Hubb wrote:2 9volts work.
This has been tested quite a bit. 2 9 volt batteries will provide more current to the sprinkler valve with 18 volts of direct current than it will draw on 24 volts AC. This is due to AC inductance limits the current in the AC circuit. DC is limited by the coil resistance.
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SP00K
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Thu Aug 06, 2009 5:51 pm

Okay, I hope I saved the solenoid attachments from my last project.

Junk hunting!
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