new piston gun now with damage pics

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.
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super spuder
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Sat May 12, 2007 3:27 pm

yea, i think mor like 20 times thicker, abs is 1/4 inch thinck :lol: hmmm. does anyone remember seeing a pressure rating on coke bottles? oh yea, thats right, there is none. hi, is that similar to the one you use in your gun?
trying to decide on a new project, probably something small.
keep_it_real
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Sat May 12, 2007 3:35 pm

According to your diagram, that would make this a chamber sealer. Does the duct tape make a seal around the hockey pucks?

Hi: soda bottles are made to handle some pressure because they are carbonated. Just because something is thicker doesn't mean it can handle more pressure.
Last edited by keep_it_real on Sat May 12, 2007 3:41 pm, edited 1 time in total.
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super spuder
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Sat May 12, 2007 3:40 pm

no all the air leaks around the duck tape , hehehe, yea the duck tape creates a perfect seal around the hockey pucks inside the T up to 30 psi anyways :) i don't know if that seal will last at 100psi.
trying to decide on a new project, probably something small.
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hi
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Sat May 12, 2007 3:45 pm

no, it is a barrel sealer. it seals against the barrel, not the chamber. a chamber sealer seals against the chamber and the piston is vertical, not horizontal.

supper spuder- yes, that is exactly how my piston is set up, mine is just smaller.
"physics, gravity, and law enforcement are the only things that prevent me from operating at my full potential" - not sure, but i like the quote

you know you are not an engineer if you have to remind yourself "left loosy righty tighty"
keep_it_real
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Sat May 12, 2007 3:59 pm

Every single barrel sealer I've seen does not look like this. The piston has a sealing face of rubber on the piston that actually seals off the barrel. This seals the chamber off from the barrel around the piston not on the face. Anyway, I guess we're just arguing about a name so I'll shut up.
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hi
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Sat May 12, 2007 4:17 pm

i guess i did the impossible on accident......

http://www.spudfiles.com/forums/little- ... t7570.html

yes thats my gun and yes its a barrel sealer and yes it works and yes it seals against the barrel and yes its a barrel sealer. ohh, did i mention it seals against the barrel?
"physics, gravity, and law enforcement are the only things that prevent me from operating at my full potential" - not sure, but i like the quote

you know you are not an engineer if you have to remind yourself "left loosy righty tighty"
keep_it_real
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Sat May 12, 2007 4:29 pm

Your valve and super spuder's valve are different. Yours is a barrel sealer like you said. His is a chamber sealer.

Did you look at his diagram? Do you see a barrel extending into the tee?

The only thing I could think of that would make this a barrel sealer is the piston stopper. He could have some kind smaller diameter pipe on there that the piston seals against but I can't see any rubber on the piston so that's doubtful.
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joannaardway
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Sat May 12, 2007 5:34 pm

I too somewhat doubt that this cannon will be a success.

Of course, if you can prove it does, then you have my utter apologies and severe confusion to make up for it.

I would reserve my apologies for after the event, but I'll probably need to be assigned to a mental hospital if you succeed (muttering: "Physics is wrong, it shouldn't work." over and over), so I have to tell you this in advance.

Just letting you know. And by the way, if, as is likely, you fail, I have one of my brother's (much coveted) extreme idiocy awards to give out as a consolation.
Novacastrian: How about use whatever the heck you can get your hands on?
frankrede: Well then I guess it won't matter when you decide to drink bleach because your out of kool-aid.
...I'm sorry, but that made my year.
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super spuder
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Sat May 12, 2007 5:48 pm

Image
my image seems to be confusing people, the barrel is the piece that goes up. and the chamber goes off to the left, i have no idea if it is a chamber or a barrel sealing valve, it kinda seals both at the same time.
trying to decide on a new project, probably something small.
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noname
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Sat May 12, 2007 6:02 pm

Hi, you are dead wrong. That's a chamber sealing valve, and there's no way duct tape will seal it. You'd also need an equilization hole, which is literally impossible for the piston setup he has.
Look in the Spudtech Archive in the Pneumatics section. There's a sticky on piston valves, chamber and barrel sealing.
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super spuder
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Sat May 12, 2007 6:05 pm

why on earth would i need an equilization hole. i built theis cannon to not have an equilization hole, because then the only air that escapes the chamber is through the barrel.
trying to decide on a new project, probably something small.
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noname
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Sat May 12, 2007 6:10 pm

You'd need an equilization hole because air will fill the chamber and push the piston; no air will get to the exhaust area unless you have 2 fill valves, which you don't.
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frankrede
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Sat May 12, 2007 6:54 pm

super spuder wrote:The piston is not that heavy actually. edit @ frankred. i did research but i can not get pressure rated parts within 60 minutes (one hour) of my house any bigger than 1.5 inch. and as for the piston. i have a better piston planed. but i do not have the tools right now to make it.
60 painless minutes in a car,or countless hours in the operating room while they remove broken pieces of plastic from your flesh?
Current project: Afghanistan deployment
rad14701
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Sat May 12, 2007 6:58 pm

Oh, my aching head...!!!

Based on the last diagram and comments by super spuder, I can see several "issues" which need to be addressed... If the "barrel" is at the top, the "chamber" is to the left, and the "pilot chamber" is to the right, then we can assume the following...

Yes, it is a chamber sealer...

There needs to be a way for both the pilot and air chambers to fill, either via an equalization passage through the center bolt or through an external equalization tube... The two chambers have to stay equalized until the gun is piloted and the air needs to get from one end to the other in order to fill...

You will need some type of sleeve to keep the piston from jamming as it slides away from the air chamber towards the pilot chamber - depending on the Tee used...

And, although I shouldn't need to be pointing it out, rather than arguing and criticizing one anothers messages, why not just focus on helping with the task at hand... People don't come here to be criticized, they come here looking for help - so give help instead of criticism...
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hi
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Sat May 12, 2007 7:23 pm

ohh, ok, now i see, sorry no name.... i thought he simply left out the barrel to save time. now i see what you mean ... sorry.

now what i think about it, what will make the piston slide back?
"physics, gravity, and law enforcement are the only things that prevent me from operating at my full potential" - not sure, but i like the quote

you know you are not an engineer if you have to remind yourself "left loosy righty tighty"
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