Login    Register
User Information
Username:
Password:
We are a free and open
community, all are welcome.
Click here to Register
Sponsored
Who is online

In total there are 78 users online :: 4 registered, 0 hidden and 74 guests


Most users ever online was 155 on Mon Aug 15, 2016 1:40 am

Registered users: Bing [Bot], Doodmens, Google Adsense [Bot], Yahoo [Bot] based on users active over the past 5 minutes

The Team
Administrators
Global Moderators
global_moderators.png CS

tell me what u think

Post questions and info about combustion (flammable vapor) powered cannons here. This includes discussion about fuels, ratios, ignition systems, safety, and anything else relevant.
Sponsored 
  • Author
    Message

tell me what u think

Unread postAuthor: nate_003 » Mon Mar 26, 2007 9:57 pm

i was looking at these the other day and thought hmmmmm maybe i can use this as a combustion chamber.......well i thought i would ask you guys what you think before i get alot of time and mony invested in it.

tell me what you think....




ps. its a 5 gal. water jug
  • 0

Attachments
dcp_2186.jpg
side shot
dcp_2187.jpg

nate_003
Private First Class
Private First Class
 
Posts: 29
Joined: Fri Feb 09, 2007 9:01 pm
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Mon Mar 26, 2007 9:59 pm

That should take the 40-odd psi combustions produce... and in the event that it doesn't, it will rupture rather than shatter so no real danger from shrapnel either.
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: nate_003 » Mon Mar 26, 2007 10:05 pm

i thought maybe use propane as a propellent......and maybe a 2" wide barrel.
  • 0


nate_003
Private First Class
Private First Class
 
Posts: 29
Joined: Fri Feb 09, 2007 9:01 pm
Reputation: 0

Unread postAuthor: benstern » Mon Mar 26, 2007 10:08 pm

It will rupture I can guarentee that. But i see it as a moderatly safe rupture.
  • 0

User avatar
benstern
Donating Member
Donating Member
 
Posts: 909
Joined: Wed Sep 21, 2005 8:24 pm
Reputation: 0

Unread postAuthor: Fnord » Mon Mar 26, 2007 10:15 pm

I think the mythbusters blew one of these up at above 60 psi, and it tore down the side. Just wrap it in ducttape and it should take the pressure.
  • 0

User avatar
Fnord
Major General
Major General
 
Posts: 2244
Joined: Tue Feb 13, 2007 9:20 pm
Location: Pripyat
Reputation: 7

Unread postAuthor: Velocity » Mon Mar 26, 2007 10:22 pm

_Fnord wrote:I think the mythbusters blew one of these up at above 60 psi, and it tore down the side. Just wrap it in ducttape and it should take the pressure.


Duct tape is not going to do anything. If their is enough force to split that plastic bottle, why would a few thin layers of relatively easy to rip (BY HAND!!) tape do anything at all?

Answer: They would not
  • 0

User avatar
Velocity
Brigadier General
Brigadier General
 
Posts: 1039
Joined: Tue Feb 07, 2006 5:42 pm
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Mon Mar 26, 2007 10:23 pm

_Fnord wrote:I think the mythbusters blew one of these up at above 60 psi, and it tore down the side. Just wrap it in ducttape and it should take the pressure.


There's a difference between the momentary pressure generated by combustion and the constant pressure in a pneumatic chamber, it should be fine even without the duct tape.
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Sponsored

Sponsor
 


Unread postAuthor: From_Hamsterdam » Mon Mar 26, 2007 10:28 pm

Water bottles are not designed to handle pressure. Coke bottles have to contain a pressured liquid(technically it's the gas) so they have to be able to handle pressure. Water bottles on the other hand only have to contain water so there is no need for them to be pressure rated. water bottles can handle a little bit of pressure, if they are left out in the sun the air/water will expand a little.

it is a big combustion chamber so it might reach high enough pressure to burst. also because it is short with a large diameter it will have a large flame front thus faster burning.

Even if there is only a rupture anything/anyone near it could receive bad burns.

if you do make it i would suggest firing it from a decent distance away and not holding on to the handle!
  • 0


From_Hamsterdam
Staff Sergeant
Staff Sergeant
 
Posts: 110
Joined: Thu Feb 15, 2007 8:26 pm
Reputation: 0

Unread postAuthor: MrCrowley » Mon Mar 26, 2007 10:59 pm

Wrong section....read :evil: When you have made it into a gun feel free to post it here.
  • 0

User avatar
MrCrowley
Moderator
Moderator
 
Posts: 10207
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Country: New Zealand (nz)
Reputation: 4

Unread postAuthor: Fnord » Tue Mar 27, 2007 7:21 am

rmich732 wrote:Duct tape is not going to do anything. If their is enough force to split that plastic bottle, why would a few thin layers of relatively easy to rip (BY HAND!!) tape do anything at all?

Answer: They would not


I've tested a 2 liter bottle to 180 psi with a few layers of duct tape, and it didn't explode. There is a difference in the way enegy is exerted when youre tearing tape and when it is stretched by an expanding chamber. Try to rip it by pulling on the ends and see how easy it is. After looking at the bottle more closely I agree it wouldnt work as well because of the way the bottle is shaped compared to a normal round one.
  • 0

User avatar
Fnord
Major General
Major General
 
Posts: 2244
Joined: Tue Feb 13, 2007 9:20 pm
Location: Pripyat
Reputation: 7

Unread postAuthor: nickz » Tue Mar 27, 2007 1:37 pm

  • 0


nickz
Private First Class
Private First Class
 
Posts: 32
Joined: Mon Mar 26, 2007 2:30 pm
Reputation: 0

Unread postAuthor: nate_003 » Wed Mar 28, 2007 10:45 pm




thankes nickz thats exactaly what i was looking for but wait... if theres going to be a pro ject tile in there the bottel will be under more preasure than whith out but i think it should be fine.
  • 0


nate_003
Private First Class
Private First Class
 
Posts: 29
Joined: Fri Feb 09, 2007 9:01 pm
Reputation: 0

Unread postAuthor: A-98 » Wed Mar 28, 2007 10:54 pm

lol, i loved his look in the end *glance left, glance right* "nice"

i think it should work, and it will probably hold the pressure. however, i would suggest that you wrap it in chicken wire if you are concerned. if it survives the first 10 firings, it should live.
  • 0

There are rules, and then there are hundred dollar bills.
User avatar
A-98
Brigadier General
Brigadier General
 
Posts: 921
Joined: Thu Apr 27, 2006 7:41 pm
Location: Santa Barbara, CA
Reputation: 0

Unread postAuthor: paaiyan » Wed Mar 28, 2007 10:57 pm

rmich732 wrote:
_Fnord wrote:I think the mythbusters blew one of these up at above 60 psi, and it tore down the side. Just wrap it in ducttape and it should take the pressure.


Duct tape is not going to do anything. If their is enough force to split that plastic bottle, why would a few thin layers of relatively easy to rip (BY HAND!!) tape do anything at all?

Answer: They would not


You underestimate the power of duct tape in mass quantities. The stuff tears easily the way you're describing, but even pressure in a linear fashion will not so easily rupture the tape.
  • 0

User avatar
paaiyan
Major General
Major General
 
Posts: 2140
Joined: Wed Dec 27, 2006 10:03 pm
Location: Central Oklahoma
Country: United States (us)
Reputation: 1

Unread postAuthor: nate_003 » Wed Mar 28, 2007 11:08 pm

A-98 wrote:lol, i loved his look in the end *glance left, glance right* "nice"

i think it should work, and it will probably hold the pressure. however, i would suggest that you wrap it in chicken wire if you are concerned. if it survives the first 10 firings, it should live.



ya that look was like WOW!!!!!!!!!!!! :shock:
  • 0


nate_003
Private First Class
Private First Class
 
Posts: 29
Joined: Fri Feb 09, 2007 9:01 pm
Reputation: 0

Next

Return to Combustion Cannon Discussion

Who is online

Registered users: Bing [Bot], Doodmens, Google Adsense [Bot], Yahoo [Bot]

Reputation System ©'