HELP Im a Newb And i Wanna Build A Large Scale Cannon

[origin unknown]

If you are going for the 155mm howitzer look, take a look at this simple idea for a combustion cannon design I drew up.

[DYI]

Let me first tell you that there is no substitute for building big. You just can't beat the sheer fun of it.

Now, for building any launcher on a massive scale there are also a few problems involved.
1. For pneumatics-
Require large scale supply of compressed gas
Require a valve with large porting, often requiring custom machining and lots of money.
Require supply of large pressure rated parts, which are also expensive
Require a long barrel to make use of all the available power
Ammo gets expensive and difficult to build above 2" bore
Requires the skill necessary to seal homemade pressure vessels of a large size

2. For combustions-
Require large, accurate propane meter
Require numerous working spark gaps, and the circuits to operate them
Require large scale venting and fuel/air mixing systems

3. For hybrids-
All of the above, multiplied by two

I would personally recommend that you build at least one smaller launcher of each type, just to get the feel of it and to practice designing things yourself. After that, you can decide which you want to undertake on a larger scale. And don't make this look like a generic punkin' chunkin' gun. I hate those. Good luck with this project.

[spec4soldier]

Origin Unknown Thanks for the spring idea that will add a cool effect to what i have in mind. I am planning on building , umm i guess its a Coaxial Combustion Cannon.... big barrel with smaller inside. I would upload a pic i drew up but not sure how yet.[/img]

[Hubb]

It may be easier to start small but it will be so much more manly to build a huge one.

As far as pics, either add an attachment (through the "Add Reply" button at the bottom or upload a pic into an image hosting site (I would say photobucket but some people here will bash me for it) then follow their instructions.

@wangpushups: Just a thought. Was it not too long ago you posted a topic on "noob bashing" because someone did you the same way?

[Zen///]

(I would say photobucket but some people here will bash me for it)

Why?
Imageshack is full of ads, and photobucket has a nice clean layout.

[watto]

I think you should do a bit of reading on piston cannons, god knows I'm not the right person to explain it to you , start here maybe http://www.spudfiles.com/spud_wiki/inde ... ston_valve

See I told him to search but I wasn't mean about it

[spec4soldier]

Heres what i have drawn up to think about doing . Still needs work. Its a rough drawing on my computers paint program . i want the barrel to be about 7 to 10 feet long and the chamber im guessing roughly 3 feet long. Im not certain on the dimensions of the chamber and really need input. Thanks

[watto]

I don't know much about combustion guns but in that picture the barrel is sleeved inside another bit of pipe, whats the point of that?

[Hubb]

Try using this as help:
http://www.spudfiles.com/forums/my-civi ... 11006.html

[Zen///]

To make it stronger or more of a asthetic look...

Some people sleeve copper barrels with pvc to make it straight and more durable.

[spec4soldier]

No ive just seen alot of people with the coaxial design and since it may take more juice and more chamber to fire properly with just the larger barrel , i decided that this might be the way to go . Not only have people sleeved copper barrels , i have noticed that some have also sleeved pvc as well. This is just to keep their barrels from bowing or breaking from the force of the object being fired, from what i can gather anyhow.

[watto]

I guess it might make it look better, but the reason people usually sleve the barrel inside the chamber is so a piston can push up against the barrel and seal it.

[spec4soldier]

Well Watto thats why im posting this forum .... to get more information on the subject. Im lookin for as much help as i can get and hopefully i can get this design perfected and ready to build as soon as i get home.

For everyone else let me know what you think and what might need to be done because i dont know the best route for a spud gun

[Hubb]

Here is another cannon you may can get ideas from. Granted, this one is pneumatic, but it can be made into a combustion (if you really want).

[MikeNice]

Hey spec4 - hope you get all you need to make your cannon. My advice for the cannons - there is nothing like experience, start small. Build a few cool combustions / pneumatics, THEN go massive once you have a working knowledge of the concepts and theories.

Anything you want to do is available with enough money. A MASSIVE is going to be expensive. Expensive materials, fuel, and projectiles. But fun as hell if you can ever get it built. Keep me poasted.

As far as your service to my country goes, thank you for having the courage to volunteer to defend our great nation.

email me anytime.