Copper Marble Cannon

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.
Post Reply
User avatar
PCGUY
Owner
Owner
United States of America
Posts: 1434
Joined: Wed Aug 18, 2004 10:54 pm
Location: Illinois
Has thanked: 2 times
Been thanked: 26 times
Contact:
Contact PCGUY

Mon Jan 31, 2005 7:36 pm

<div align="center">COPPER MARBLE CANNON

Provided By - GalFisk </div>
Attachments
This is a gun I've always wanted to build, a pneumatic marble gun out of copper. It has a 2m long barrel of 18mm copper pipe, a perfect fit for 16mm (5/8&amp;amp;quot;) marbles. The chamber is made out of 1m 28mm copper pipe, with couplers the total chamber volume is about 580cc. All copper parts are sweated (soldered) together, with a 35mm brass coupling on the back end, to which the blowgun is connected. The back of the coupling can be screwed off to allow access to the valve. This picture was taken after the gun was polished and coated with several layers of metal varnish. I'm going to add barrel support, some sort of shoulder strap, possibly a tripod, and a CO2 setup. The gun hasn't been tested with marbles yet, but it has been dry-fired at up to 180 psi, at which it gives a loud crack. The air from a dry firing blasts great holes in newspaper.
This is a gun I've always wanted to build, a pneumatic marble gun out of copper. It has a 2m long barrel of 18mm copper pipe, a perfect fit for 16mm (5/8&amp;quot;) marbles. The chamber is made out of 1m 28mm copper pipe, with couplers the total chamber volume is about 580cc. All copper parts are sweated (soldered) together, with a 35mm brass coupling on the back end, to which the blowgun is connected. The back of the coupling can be screwed off to allow access to the valve. This picture was taken after the gun was polished and coated with several layers of metal varnish. I'm going to add barrel support, some sort of shoulder strap, possibly a tripod, and a CO2 setup. The gun hasn't been tested with marbles yet, but it has been dry-fired at up to 180 psi, at which it gives a loud crack. The air from a dry firing blasts great holes in newspaper.
marblegun.jpg (7.83 KiB) Viewed 11318 times
The bulk of the soldering was on the tee, where the chamber, barrel and connector all come together. It was a bit complicated to get everything lined up, since I had to heat and solder all the parts in sequence, to prevent the heating one joint from breaking another. The barrel came on slightly askew, but with some grinding on the end, it seals perfectly. The soldering on the brass connector wasn't airtight in the first try, probably because I hadn't heated the large brass fitting enough, but it was successful on a second try. A piece of 28mm pipe is used to connect the brass fitting to the tee, the piston slides inside this piece of pipe. You can see I've begun to polish the chamber.
The bulk of the soldering was on the tee, where the chamber, barrel and connector all come together. It was a bit complicated to get everything lined up, since I had to heat and solder all the parts in sequence, to prevent the heating one joint from breaking another. The barrel came on slightly askew, but with some grinding on the end, it seals perfectly. The soldering on the brass connector wasn't airtight in the first try, probably because I hadn't heated the large brass fitting enough, but it was successful on a second try. A piece of 28mm pipe is used to connect the brass fitting to the tee, the piston slides inside this piece of pipe. You can see I've begun to polish the chamber.
Polished copper looks very nice.
Polished copper looks very nice.
polish.jpg (6.65 KiB) Viewed 11318 times
This is the assembled valve. the hose barb connected to the blowgun in the picture is a perfect fit for the air chuck on a 12V compressor. I also have a quick-disconnect fitting for connecting the gun to an ordinary compressor. <br /><br />The parts of the valve have been changed a bit since the pictures were taken, and I've definitely forgotten the cable to my camera in Norway, but I'll get some updated pictures of it as soon as possible. The concept drawing of the valve also needs to be updated accordingly.<br />UPDATES!<br /><br />There is a shopping cart stuck in the ice at the lake, which I used for target and support. first shot was through the wheel, which was no match at all.
This is the assembled valve. the hose barb connected to the blowgun in the picture is a perfect fit for the air chuck on a 12V compressor. I also have a quick-disconnect fitting for connecting the gun to an ordinary compressor.

The parts of the valve have been changed a bit since the pictures were taken, and I've definitely forgotten the cable to my camera in Norway, but I'll get some updated pictures of it as soon as possible. The concept drawing of the valve also needs to be updated accordingly.
UPDATES!

There is a shopping cart stuck in the ice at the lake, which I used for target and support. first shot was through the wheel, which was no match at all.
valve.jpg (16.55 KiB) Viewed 11318 times
I did some range shots with a relatively flat trajectory, I think I can shoot across the lake at good elevation (400m) but there's popular a hiking trail all the way around it so I won't try. The lake is about a mile long so I can do range tests that way when there's no people on the ice, but I don't have any way to see where the marble lands. A smoke marker or something would be nice... <br />Another shot at the bars of the cart bent one of them out of shape.
I did some range shots with a relatively flat trajectory, I think I can shoot across the lake at good elevation (400m) but there's popular a hiking trail all the way around it so I won't try. The lake is about a mile long so I can do range tests that way when there's no people on the ice, but I don't have any way to see where the marble lands. A smoke marker or something would be nice...
Another shot at the bars of the cart bent one of them out of shape.
wheel.jpg (6.46 KiB) Viewed 11318 times
I had brought some junk CDs I decided to shoot
I had brought some junk CDs I decided to shoot
The first shot hit near the edge, and tore successively bigger holes in the CDs. The hole in the first CD was about the size of a marble, the last one was about five times as large.
The first shot hit near the edge, and tore successively bigger holes in the CDs. The hole in the first CD was about the size of a marble, the last one was about five times as large.
A second shot through the middle split some of them in to, and broke a large hole in the middle of others.
A second shot through the middle split some of them in to, and broke a large hole in the middle of others.
cd1st.jpg (13.98 KiB) Viewed 11318 times
I also put a nice dent in the frame of the shopping cart with one marble.
I also put a nice dent in the frame of the shopping cart with one marble.
I actually found one of the marbles, its shape suggests that it was the one I used to make the dent. A bit in the center of the round part was crushed from the initial contact, when the marble was stopped by the metal, the parts that wasn't braced against the inside of the dent came off and was probably pulverized against the metal in front.
I actually found one of the marbles, its shape suggests that it was the one I used to make the dent. A bit in the center of the round part was crushed from the initial contact, when the marble was stopped by the metal, the parts that wasn't braced against the inside of the dent came off and was probably pulverized against the metal in front.
dent.jpg (16.19 KiB) Viewed 11318 times
I'm very happy with my first pneumatic.<br /><br />It's not done (crappy varnish peels off so I need something better, CO2 setup, better barrel support, pressure meter, etc), but it's working, and working very well. I've had some minor sealing problems using the bike pump as air source, but the valve is easy to take apart and fix in the field.<br /><br />Someone had thrown away a perfectly good orange by the road, so I took it.
I'm very happy with my first pneumatic.

It's not done (crappy varnish peels off so I need something better, CO2 setup, better barrel support, pressure meter, etc), but it's working, and working very well. I've had some minor sealing problems using the bike pump as air source, but the valve is easy to take apart and fix in the field.

Someone had thrown away a perfectly good orange by the road, so I took it.
brokenmarble.jpg (11.22 KiB) Viewed 11318 times
And shot it. <br /><br />Nothing overly dramatic, just a 'thwap' sound and a hole. If the orange is still there tomorrow I might shoot it with the combustion gun.
And shot it.

Nothing overly dramatic, just a 'thwap' sound and a hole. If the orange is still there tomorrow I might shoot it with the combustion gun.
orange.jpg (7.11 KiB) Viewed 11318 times
If the snow seems a little bleak in this and other pictures, it's because I've adjusted the gamma. The snow throws off the compensation in the camera, and some pictures became overly dark. <br />Denting metal is fun (or something). It doesn't show very well in the picture, but there's powdered glass stuck in the dent.
If the snow seems a little bleak in this and other pictures, it's because I've adjusted the gamma. The snow throws off the compensation in the camera, and some pictures became overly dark.
Denting metal is fun (or something). It doesn't show very well in the picture, but there's powdered glass stuck in the dent.
orangeshot.jpg (4.08 KiB) Viewed 11318 times
This is about 3mm thick chromated steel.
This is about 3mm thick chromated steel.
I hung a tin can on the barrel and fired through it, it was torn apart at the seam.
I hung a tin can on the barrel and fired through it, it was torn apart at the seam.
metal.jpg (9.66 KiB) Viewed 11318 times
I also shot at the end of an old log, the marble was firmly embedded in the wood.
I also shot at the end of an old log, the marble was firmly embedded in the wood.
seamhole.jpg (9.06 KiB) Viewed 11318 times
But it only took the bark off of a fresh tree.
But it only took the bark off of a fresh tree.
marblelog.jpg (17.97 KiB) Viewed 11318 times
The picture is accurate, this tree is actually horizontal at the point where I hit it. The damage will grow shut over the summer. If you shoot soft projectiles the shreds will explode outwards when the projectile hits the wood, and can tear large holes in the bark. <br /><br />Finally, what I was planning to do was to see how many tin cans I could shoot a marble through. I took the eight ones I had brought and stacked them together, and braced them against the shopping cart.
The picture is accurate, this tree is actually horizontal at the point where I hit it. The damage will grow shut over the summer. If you shoot soft projectiles the shreds will explode outwards when the projectile hits the wood, and can tear large holes in the bark.

Finally, what I was planning to do was to see how many tin cans I could shoot a marble through. I took the eight ones I had brought and stacked them together, and braced them against the shopping cart.
birchhole.jpg (19.45 KiB) Viewed 11318 times
Then I loaded a marble, pumped the gun as high as I could, donned safety glasses then lined up the barrel and fired.<br /> <br />The marble went through the bottom of six cans before stopping with a big dent in the seventh. The seventh can was pounded into the eighth, they couldn't be separated by hand afterwards. The order in the picture isn't the order the cans were stacked in.
Then I loaded a marble, pumped the gun as high as I could, donned safety glasses then lined up the barrel and fired.

The marble went through the bottom of six cans before stopping with a big dent in the seventh. The seventh can was pounded into the eighth, they couldn't be separated by hand afterwards. The order in the picture isn't the order the cans were stacked in.
canstack.jpg (16.48 KiB) Viewed 11318 times
Top view
Top view
The marble was chipped on both sides.
The marble was chipped on both sides.
holestop.jpg (12.29 KiB) Viewed 11318 times
It was given an honorary escort of two other marbles to some place out on the ice. The cans went in the metal bin at the recycling station. <br /><br />Shot some more today, since it was very nice weather unlike last weekend. I improved the seal on the bike pump, so I could get the gun up to about 110 psi this time. I'm probably going to buy a big-ass CO2 tank and regulator, unless it's too expensive or cumbersome. <br /><br />First, I decided to take it out on an old sandal
It was given an honorary escort of two other marbles to some place out on the ice. The cans went in the metal bin at the recycling station.

Shot some more today, since it was very nice weather unlike last weekend. I improved the seal on the bike pump, so I could get the gun up to about 110 psi this time. I'm probably going to buy a big-ass CO2 tank and regulator, unless it's too expensive or cumbersome.

First, I decided to take it out on an old sandal
marbledamage.jpg (1.76 KiB) Viewed 11318 times
The marble went straight through, and had enough energy left to put a nice dent in one of the bars on the shopping cart
The marble went straight through, and had enough energy left to put a nice dent in one of the bars on the shopping cart
Then I set up an old dinner plate, that had decided to break for no apparent reason. The glue job wasn't satisfactory, so I decided to do the best out of the situation
Then I set up an old dinner plate, that had decided to break for no apparent reason. The glue job wasn't satisfactory, so I decided to do the best out of the situation
bardent.jpg (5.98 KiB) Viewed 11318 times
This result was more satisfactory.
This result was more satisfactory.
plate.jpg (12.72 KiB) Viewed 11318 times
With my newfound increase in pressure, I had to do another penetration test. I didn't have enough tin cans, but I had a lot of jar lids that were about as thick. I filled two tin cans with lids and fired a shot, which made a nice hole.
With my newfound increase in pressure, I had to do another penetration test. I didn't have enough tin cans, but I had a lot of jar lids that were about as thick. I filled two tin cans with lids and fired a shot, which made a nice hole.
The marble went through six lids and was stuck halfway through the seventh. The eighth lid, the last one in the first can, had a hole in it, and the bottom of the can was dented.
The marble went through six lids and was stuck halfway through the seventh. The eighth lid, the last one in the first can, had a hole in it, and the bottom of the can was dented.
I then reassembled the stack of lids, and shot four marbles simultaneously into the cans. Two of the marbles were completely pulverized.
I then reassembled the stack of lids, and shot four marbles simultaneously into the cans. Two of the marbles were completely pulverized.
lids.jpg (15 KiB) Viewed 11318 times
And the hole through the first can of lids was completed.
And the hole through the first can of lids was completed.
The chamber size seems to be quite sufficient on this gun, according to GGDT I'll gain 4 fps by increasing chamber size eight times. Barrel length matters a little more, with twice the barrel (an unwieldy length of 4m) I'll gain about 60 fps at 100 psi. Projectile weight and pressure seems to be the most important factors though, and with a metal gun I can go a bit higher than with PVC. <br />I went out and did a few more tests, because I wondered if I could shoot through the leather on the top of sandal. That was no problem.
The chamber size seems to be quite sufficient on this gun, according to GGDT I'll gain 4 fps by increasing chamber size eight times. Barrel length matters a little more, with twice the barrel (an unwieldy length of 4m) I'll gain about 60 fps at 100 psi. Projectile weight and pressure seems to be the most important factors though, and with a metal gun I can go a bit higher than with PVC.
I went out and did a few more tests, because I wondered if I could shoot through the leather on the top of sandal. That was no problem.
sun.jpg (9.64 KiB) Viewed 11318 times
The leather isn't particularly thick or strong, I do have some old leather shoes, but they're still far too nice to be used as targets. They're my spudding shoes, which I use when I don't want to mess up my nice pair. <br /><br />I also shot the top of the failed fan-in-a-bottle, the plastic kind of peeled off, and closed the hole after the marble had passed through. The exit hole (right) was much bigger that the entry.
The leather isn't particularly thick or strong, I do have some old leather shoes, but they're still far too nice to be used as targets. They're my spudding shoes, which I use when I don't want to mess up my nice pair.

I also shot the top of the failed fan-in-a-bottle, the plastic kind of peeled off, and closed the hole after the marble had passed through. The exit hole (right) was much bigger that the entry.
sandalvandal.jpg (14.47 KiB) Viewed 11318 times
I also shot at the empty casing from a broken 12V compressor, again the exit hole was much bigger.
I also shot at the empty casing from a broken 12V compressor, again the exit hole was much bigger.
bottlentry.jpg (17.22 KiB) Viewed 11318 times
I also brought some old particle board from a speaker somebody had dumped in the woods. It was about 2 cm (.78&amp;quot;) thick, but not in it's best shape. Again notice the bigger exit hole.
I also brought some old particle board from a speaker somebody had dumped in the woods. It was about 2 cm (.78&quot;) thick, but not in it's best shape. Again notice the bigger exit hole.
compexit.jpg (11.5 KiB) Viewed 11318 times
Finally, I decided to shoot along the edge of the board to see what would happen. It went about 5cm (2&amp;quot;) through the board before going out at one side.
Finally, I decided to shoot along the edge of the board to see what would happen. It went about 5cm (2&quot;) through the board before going out at one side.
pbexit.jpg (2.33 KiB) Viewed 11318 times
pbfront.jpg
pbfront.jpg (5.33 KiB) Viewed 11318 times
Last edited by PCGUY on Mon May 08, 2006 10:21 pm, edited 1 time in total.
Yes, I am the guy that owns & operates SpudFiles (along with our extremely helpful moderators).
Top
User avatar
theexp
Specialist
Specialist
Posts: 157
Joined: Sun Oct 03, 2004 3:19 pm
Location: Chapel Hill NC
Contact:
Contact theexp

Wed Feb 02, 2005 8:25 pm

"hey johnny, you want ta play Marble...."
that things kinda scares me. lol, Real nice job on ANOTHER COPPER CANNON...
Top
Hunter
Recruit
Recruit
Posts: 2
Joined: Thu Feb 03, 2005 9:45 pm
Location: seminole ,tx

Wed Feb 16, 2005 3:06 pm

hey dude that thing is awsome it looks really simple id like to build one but i dont know what id use for a burst disk scary nice job truly nice
Top
User avatar
BC Pneumatics
Sergeant
Sergeant
Posts: 1053
Joined: Tue Jan 18, 2005 6:55 pm
Location: Fresno, CA
Contact:
Contact BC Pneumatics

Donating Members

Wed Feb 16, 2005 6:36 pm

Alumminum foil works great. Just layer it for higher pressures.
Top
spudshot
Sergeant
Sergeant
Posts: 1036
Joined: Sun Oct 03, 2004 7:16 am

Thu Feb 17, 2005 8:58 pm

he doesnt use a burst disk though does he?
i've built a copper cannon like taht, a 1/2" barrel, but i cant find any damn marbles to fit it! also the piston destroys itself, but that'll change when i get my 1/4" brass washers drilled
Image
Top
User avatar
fred_roux
Private 3
Private 3
Posts: 46
Joined: Mon Feb 14, 2005 4:29 pm
Location: Québec (canada)

Sun Apr 10, 2005 3:48 pm

nice damage pics :twisted:
Top
User avatar
CS
Moderator
Moderator
Posts: 1837
Joined: Fri Feb 18, 2005 5:32 pm
Location: Southern Utah

Donating Members

Sun Apr 10, 2005 4:00 pm

I like the gun nice sodering job.
Top
GalFisk
Specialist
Specialist
Sweden
Posts: 113
Joined: Mon Feb 28, 2005 4:06 am
Been thanked: 4 times

Mon May 09, 2005 12:38 am

Thanks for the comments. It's using a normal barrel-sealing piston valve. More cannon and damage pics can be found in my gallery: http://galfisk.kaaven.net/gallery
Top
hardcor22
Private
Private
Posts: 3
Joined: Mon May 02, 2005 11:29 pm
Location: warragul,australia

Wed Aug 17, 2005 2:34 am

Sweet gun bro i have a marble gun not copper though but shit that kicks my m.g nice good job :D :D
hardcor
Top
User avatar
rna_duelers
Staff Sergeant 3
Staff Sergeant 3
Posts: 1739
Joined: Mon Sep 26, 2005 7:07 am
Location: G-land Australia

Wed Sep 28, 2005 12:03 am

Love the look of that polished copper..I am gunna make myself a coper marble gun..hungry for more muzle velocity...All i gota do now is learn to solder the parts the gether with out making another solderd part melt..Nice damage pics..absolutly carved up those cd's
Top
bubblebathman
Private 3
Private 3
Posts: 50
Joined: Thu Sep 22, 2005 12:45 pm
Location: USA

Wed Sep 28, 2005 12:07 pm

i love the destrution pics :twisted: :twisted: :twisted: and the opper varnish idea great i should make on like it and mabye record the destrution on cam maybe :twisted: :twisted: :twisted: :twisted: :twisted:
Top
Z0Z0
Private
Private
Posts: 19
Joined: Mon Aug 14, 2006 12:00 am

Sun Nov 12, 2006 12:03 pm

nice damage pics

very nice, I sure like it

like bubblebathman said a video would be very nice

A+++++
~Z0Z0
Top
User avatar
SpudStuff
Sergeant 5
Sergeant 5
Posts: 1410
Joined: Sat Dec 10, 2005 3:55 pm
Location: Cupertino, California
Contact:
Contact SpudStuff

Sun Nov 12, 2006 12:55 pm

PLEAST DO NOT KICK UP DEAD TOPICS!
Top
User avatar
POS
Specialist 3
Specialist 3
Posts: 395
Joined: Thu Sep 14, 2006 4:19 pm

Sun Nov 12, 2006 4:03 pm

so stop answering them yourself.
Top
User avatar
SpudFarm
First Sergeant 3
First Sergeant 3
Posts: 2571
Joined: Sat Nov 04, 2006 9:39 am
Location: Norway Trondheim area

Donating Members

Sun Nov 26, 2006 5:10 am

Last edited by SpudFarm on Sun May 18, 2008 2:30 pm, edited 1 time in total.
Top
Post Reply

Return to “Pneumatic Cannons”