Building propane-oxygen fueled launcher

[super spuder]

Some of you may remember my last topic on this. I am actually going to build it now that is is nice out. I went and got this

as the chamber, it weighs 20 pounds so this cannon is not going to be portable. I might also run accetaline and oxygen in it . As for the barrel, it is probbly going to be 1 and 1/2 inch so i can shoot golf balls. i am going to use a coil and spark plug to ignight it. So just tell me if you have any comments sugestions or if you want to call me stupid, go for it. I just have one question. How thick should the barrel be?

[frocksie]

What is the volume of that chamber?

[spudthug]

what the hell was that thing??!?!? sure do it but it may be hard getting the rusted parts off.. put a union on it for a burst disk..to make it loud..of course..obviously...dur..ill stop now....

[SpudMonster]

Okay, first, a 1 1/2" barrel will not fit golfballs. It has to be a 1 1/2" SDR 21 barrel sleeved within 2" SCH 80 pipe.

Second, that bears a remarkable resemblance to the air chamber for an old piston-driven water pump such as <a href="http://www.steamengine.com.au/events/re ... .jpg">THIS ONE</a>
While they are heavy, that is due to their cast iron construction. It's heavy, but casting techniques of yore left something to be desired at times. Not only that, but cast iron does not like high tensile loads very much, or shock loads. Both of whis it would see this application.

Want my advice? Don't use that as the chamber.

[super spuder]

@spudthug that was a pressure tank for a water pump. and heat from a torch will get anything off i will go and find the volume
@SpudMonster this chamber was built to handle high water pressure, so it should not have trouble holding gass pressure

[sandman]

wouldnt heat make it worse?
would that not increase the reaction rate of iron and oxygen?

[super spuder]

it is not made of iron, and the volume is about 175 cubic inches.

[frocksie]

Is it 14in x 4in approximately?

[super spuder]

it is 10 by 4.5 plus the extra bit which is 2 by 2 aproxamatly. It is hard to tell because the bottom is bowl shaped and i don't know how thick it is yet

[cb4289]

That thing looks like it coluld kill you when you shoot it off. er. well maby not depends on what fuel you use and how thick it is.

dose my big ass make my ass look big -rosane

[frankrede]

I wouldn't trust it with oxygen.
Maybe a plain old wimpy propane shot.
But even then I would hate to see you mess with oxygen/

[noname]

I have managed not to kill myself yet, shooting my soda can gun with propane and oxygen. I'd say you're safe if you remote fire (at least 50 feet away) and you're behind something stronger than 1" plywood.

[SpudMonster]

it is not made of iron, and the volume is about 175 cubic inches.

It's rusting, it's cast, but it ist't iron! BRILLANT DEDUCTION SHERLOCK!
<img src="http://i.somethingawful.com/forumsystem ... uicide.gif">

Honestly, you are a certified dumbass.

[FeLeX]

Why are people always sh!tting their pants when they hear that some one is going to use oxygen? What if they have a very sturdy tank? I mean what kind of pressure does oxygen make that makes you all so scared of it?

[Pete Zaria]

Sorry super spuder, but I think SpudMonster is dead on right; that's a cast iron cylinder probably from a water pump or steam apparatus.
In either case, it's not made to handle extreme pressures, but even moreso, it's not made to handle extreme pressure spikes.
Especially covered in however-many-years-worth of rust.

Sorry to say it, but I'd look for a stronger chamber. Look for a scuba tank or other gas tank that's too old to be officially used anymore, or something like that. We'd hate to see something in the news about "Local teen killed by shrapnel from home-made oxygen-burning potato gun"...

If you do choose to use this thing, test fire it 50 times remotely and then THROUGHLY inspect it for signs of wear.

Peace,
Pete Zaria.