I would like your opinions on chamber diameter.

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JDP12
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Fri Apr 25, 2008 7:57 pm

Well after having all these guns that i'm in the process of building, all these fancy ones, I decided to take a step back, and build a simple little spudgun that i could easily stuff into my backpack when i go over to a friends or whatever. My dilemma is deciding the diameter of the chamber. It's mostly for looks. I want it to be around 8 - 8.5 inches long, for compactness reasons, but i'm trying to decide if i want a 3" or 2" diameter chamber.. The difference in volume is a little over 2 times as much if i went with 3", but i think the thicker pipe going to a small barrel (1" and 3/4") would look really cool.

I'm looking at burntlatke's mini L1 alot, and i can't tell what size of pipe they have- i think it might be 2 inch. I'd like it to be similar to that- does anyone know what diameter pipe they used for that chamber??

I'm also looking at Joel's mini gun here's a picture - http://www.spudtech.com/images/products/mini-me-1.jpg

Thanks
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Lentamentalisk
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Fri Apr 25, 2008 8:03 pm

that looks more on the scale of 3' tall than 8" judging by the size of the metering system and gauge.
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JDP12
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Fri Apr 25, 2008 8:03 pm

i meant the chamber length sorry, not the whole gun.. so what do you think about chamber diameter for looks?

i think i might end up going with 2"... or 3" x like 6 or 7 inch, just for chamber:barrel ratio with such a small diameter barrel... grr
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Fri Apr 25, 2008 9:22 pm

Alright, do you want a gun that will scare the living $hit out of your friends, impress then, and have something that looks good.

Get 8in of 4in pvc and 8in of 2in pvc. A screw on cap and a 4in to 2in reducer.

Now glue it all together its like 1ft 8in when completely assembled.

I built one and I mounted a chamber fan for mixing hairspray which increases the boom and distance.

My neighbor is in the military and when I shot this thing he said it sounded like a small artillery cannon going off!

Make sure you where hearing protection, I shot this thing down a 6ft long hallway with a closed door at the end, all of the sound echoed off the walls and right back at me. I was hearing ringing for about 3 hours after that!!!!

Once again this thing will impress people but its not the best performance gun (Distance/Power wise). (Add a chamber fan for better power and distance)
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JDP12
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Fri Apr 25, 2008 9:24 pm

yea, i'm more looking for performance and looks. i'm just really stuck on which diameter. 2" is a smaller chamber. 3" is like double, but looks cooler i think than 2"". i'm gonna slap a piece of 3/4" to see what each looks like.
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Fri Apr 25, 2008 9:31 pm

If its performance and looks then you should build a multi peice gun that you can assemble in sections.

You need a chamber to barrel ratio of something like .8/1 its on the wiki, if you get this right it will work fine.

I suggest using a single chamber, don't try to build multiple chambers.(Just to keep it simple and portable) and a multi piece barrel (3 sections of 1ft-2ft each).

As for looks a nice coat of black paint with some decals would look nice,

I am assuming this is just a spray the fuel in and fire cannon not a metered propane system.
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JDP12
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Fri Apr 25, 2008 9:38 pm

Yea... I lined them up... 3" looked way more badass with the wider chamber..

Nope, its metered propane :D:D:D:D . i've never built a gun that uses aerosol. Probably never will.

But yea i'll do multiple barrel sections.

Maybe even a burst disc too to improve performance. I want this gun to basically be a really advanced combustion, only miniaturized to fit into a backpack. All the bells and whistles in sort of miniature.
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Fri Apr 25, 2008 10:00 pm

I have wanted to build a propane metering system, I just don't need it.

If i was going to build an advanced combustion I would mount a hydrogen production plant on top!!!! He he he Propane is old school, its time for the new age.

Basically a sealed clear tube filled with water and two electrodes hooked up to a battery so you can see the gas forming, then two secondary tanks would collect the gas and tell you the exact pressure and when they reach the desired levels you would use a small 12v air pump to transfer the hydrogen from the secondary tanks to the main combustion chamber.

Its an ambitious idea but I am sure it could be done, sounds like something on my to do list.

Only problem is the I am not suppose to build potato guns.... ever since i showed my parents my super mini. I never posted it but it had a mini fan like 20mm inside a pill bottle with a short 4in barrel. Its fuel was butane and it was mounted on an old airsoft frame.

When I fired it there was like a 2in jet of fire that came out of the barrel not to mention the huge flash from the combustion in the bill bottle and a loud crack. After that I stopped building complex guns because the odds of it getting taken away and destroyed increased a lot.

About a year ago I built an 8ft long copper pneumatic cannon, it was like $60 to get all the stuff and I fell asleep with it in the workshop and went to check on it when I woke up. To my surprise it was gone gone gone gone gone gone gone who took it? Hmmmmmmmmmmm I want a full refund LOL!
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Fri Apr 25, 2008 10:46 pm

About a year ago I built an 8ft long copper pneumatic cannon, it was like $60 to get all the stuff and I fell asleep with it in the workshop and went to check on it when I woke up. To my surprise it was gone gone gone gone gone gone gone who took it? Hmmmmmmmmmmm I want a full refund LOL!
Damn, that sucks. Why would anyone want to steal small chunks of copper pipe anyway?
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Fri Apr 25, 2008 11:06 pm

They didn't steal it, they took it far away and through it in the trash. I don't know why they didn't recycle it! Copper can be recycled for some cash.

Just goes to show what happens to my cannons.......................
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Fri Apr 25, 2008 11:10 pm

Copper is so freaking expensive these days ... here in the US ppl will steal the wiring out of houses that are under construction, or out of air conditioners for large buildings.
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Fri Apr 25, 2008 11:13 pm

Spudgun on Crack wrote:They didn't steal it, they took it far away and through it in the trash. I don't know why they didn't recycle it! Copper can be recycled for some cash.

Just goes to show what happens to my cannons.......................
Perhaps they sold it to buy crack? :lol:
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Sat Apr 26, 2008 3:28 am

If you look at the mini L1 on latke's site you can see that the screw cap on the chamber says 2" pvc. If you were still wondering.
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JDP12
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Sat Apr 26, 2008 9:11 am

k thanks guys

message too short
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DYI
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Sat Apr 26, 2008 10:58 am

They didn't steal it, they took it far away and through it in the trash. I don't know why they didn't recycle it! Copper can be recycled for some cash.
Wait, you know who stole it? So you got your money back, right?
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