mortar

Show us your pneumatic spud gun! Discuss pneumatic (compressed gas) powered potato guns and related accessories. Valve types, actuation, pipe, materials, fittings, compressors, safety, gas choices, and more.
alkalineall
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Mon Nov 20, 2006 9:40 pm

Well this is something that I've been working absent-mindedly on for a while. Yes, I know that I used DWV fittings. I don't need to go above 60 psi ever. I takes forever to fill. My chambers are 6" and my elbows and cross are 4". The barrel is not permanent and will be replaced with a male fitting and assorted barrels. I have dry fired many times, but I live in a congested area and haven't done an open air distance test. Sorry. The exhausted air on a dry fire lifted the sheet metal lid off of my furnace and flung it a few feet. Pretty impressive. Oh, my piston is a 3" endcap plugged in the rear and sealed with a 2" gasket that I stretched around a piece of pipe. The trickiest part of this project was the piston and barrel setup as the barrel extends back into the middle of the cross for airflow reasons. The piston had to extend out into this open area to seal. It took a lot of adjusting and switching things around, but it seals every time now.
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schmanman
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Mon Nov 20, 2006 9:44 pm

how long are the barrel, chambers, etc?
Persistence is a measure of faith in yourself
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judgment_arms
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Mon Nov 20, 2006 9:50 pm

Intriguing…
Is the barrel fixed? If so at what angel is it fixed at?
If you’re comfortable with DWV fine. If it were me I wouldn’t use it,
Save for a DWV threaded cap for a breach loader.
alkalineall
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Mon Nov 20, 2006 10:51 pm

The chambers are about three feet long and I don't know how long the "barrel" . I say that in quotations because it's just a piece of pipe that I intend to cut off and add a male 3" adaptor to. The permanent barrels will probably be around 4 feet I think. The barrel area has a 22.5 degree elbow. There is an irritating story behind that . I originally intended to have barrel and chambers parallel, but while marking I didn't account for the fact that sanitary crosses, tees, etc. aren't square(at 90 degree angles). So I marked my fittings , but later decided to flip the cross fitting over for better airflow after gluing one side (you'd have to see a sanitary cross to see what I mean) and ended up with a horrible angle. So I used the 22.5 elbow to fix things :cry: . I actually kind of like the angled barrel idea now, I usually aim my other cannons like a mortar anyway, and this one is too heavy to carry/aim. Judment Arms: If I had access to pw fittings, sure I would rather use them too for peace of mind, but my fittings etc were all free from consruction leftovers excluding the cross and endcaps. Like I said I never exceed 60 psi so I'm don't lose any sleep over it.
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TalonXxX
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Mon Nov 20, 2006 11:11 pm

That is a really slick design for a mortar! Really nice, I've always wanted to make one and I really like this design. Thanks for sharing :D
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Petrie
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Mon Nov 20, 2006 11:20 pm

What does dwv mean??
is it a type of pvc ?
is it weaker?

~petrie
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MrCrowley
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Mon Nov 20, 2006 11:46 pm

you just answered your question. It non-pressure rated PVC pipe.
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experament_u2
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Tue Nov 21, 2006 12:32 am

nice cannon wat is your primary ammo going to be? nice job 8)
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killagorrila99
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Tue Nov 21, 2006 3:37 am

Try billiard balls 8)
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POS
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Tue Nov 21, 2006 12:40 pm

it should be heavy and small, looking at the barrel.
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noname
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Tue Nov 21, 2006 7:52 pm

Shake up a Coke can and stick it down the barrel. They fit pretty good.
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SpudStuff
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Tue Nov 21, 2006 7:57 pm

Wow! Very nice. I like how you put the valve in the pipe. It looks cleaner.
You shouldn't even take it to 60 PSI. The large dia. pipe can take even less pressure then 2 or 3" fittings.
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jrrdw
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Tue Nov 21, 2006 8:19 pm

Iv'e never seen anything like it, cool ! Did you dream that up all by yourself? I guess so, you built it. Cool !
alkalineall
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Tue Nov 21, 2006 10:36 pm

My 6" pipe has is rated for 180psi according to the writing along the side. The 4" I believe is 240 and the 3" 260. The area connecting to the valve is some reinforced by some 2" pipe that I slit with a band saw and slipped over the 1". Thats why you can see stainless steel screws there. The cover over the valve was my attempt to protect it from damage. I'll probably replace it with a 3/4" QEV that I got on Ebay for .99 :lol: I just need the right bushings and am too busy/lazy/cheap to go get them.
iknowmy3tables
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Wed Jan 17, 2007 6:05 pm

sweet 6" chambers, intresting cocealment of the sprikler valve
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