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 62 users online :: 6 registered, 0 hidden and 56 guests


Most users ever online was 218 on Wed Dec 07, 2016 6:58 pm

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

The Team
Administrators
Global Moderators
global_moderators.png CS

Fuel

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

Fuel

Unread postAuthor: rebalgray » Wed Feb 21, 2007 2:06 pm

What gives the largest flame and the loudest bang?

Martin
  • 0

User avatar
rebalgray
Specialist
Specialist
 
Posts: 45
Joined: Mon Feb 12, 2007 8:55 pm
Location: Crawfordsville, Indiana
Reputation: 0

Unread postAuthor: imjustpk » Wed Feb 21, 2007 3:02 pm

well there are a lot of variables to that question, instead of going for a more powerful and dangerous fuel you might want to experiment with chamber to barrel ratios
  • 0

User avatar
imjustpk
Corporal
Corporal
 
Posts: 63
Joined: Sun Jan 28, 2007 5:12 am
Reputation: 0

Unread postAuthor: chaos » Wed Feb 21, 2007 3:03 pm

Well i find with my combustion http://www.spudfiles.com/forums/viewtopic.php?t=5919&
i get a really sharp crack when i use brut24hr(black can) deodorant but as for power i do not not for it was dark and i could not see the golf ball.
i also find that camping gas for portable bbq's with a 80%butane an 20%propane give quie alot of power and a large bang upon firing

peace
  • 0

User avatar
chaos
Brigadier General
Brigadier General
 
Posts: 1205
Joined: Wed Jan 17, 2007 8:31 am
Reputation: 0

Re: Fuel

Unread postAuthor: Recruit » Wed Feb 21, 2007 4:08 pm

rebalgray wrote:What gives the largest flame and the loudest bang?

Martin


A. C4
B. H-bomb

:lol: :lol: :lol:

Seriously there is no specific best fuel. Their is on experimentation.
  • 0

User avatar
Recruit
Lieutenant Colonel
Lieutenant Colonel
 
Posts: 413
Joined: Fri Oct 06, 2006 4:26 pm
Reputation: 0

Fuel

Unread postAuthor: rebalgray » Wed Feb 21, 2007 4:16 pm

I have a 4" X 11" chamber with two different barrels. One is 1.5" X 3' The other one is 1.25" by 3'. I'm not looking for power just a bang and a lot of flame. It has metered propane on it now. I haven't fired it yet. I'm still putting it together.

Martin
  • 0

User avatar
rebalgray
Specialist
Specialist
 
Posts: 45
Joined: Mon Feb 12, 2007 8:55 pm
Location: Crawfordsville, Indiana
Reputation: 0

Unread postAuthor: LGM » Wed Feb 21, 2007 5:54 pm

For flame use a bit too much gasoline, make sure that you still have enough to fire it though. Propane gives a nice jet of blue flame at night, but not a fireball. If you just want flame and don't need to shoot something, spray WD-40 down the barrel, meter the propane, and watch the flames.
  • 0


LGM
Captain
Captain
 
Posts: 320
Joined: Mon Jan 22, 2007 3:06 pm
Reputation: 0

Unread postAuthor: rebalgray » Wed Feb 21, 2007 7:26 pm

Thanks for the help. I'll give it a try. Right now i'm scaring the hell out of the dogs with my pill bottle mini.....lol....
  • 0

User avatar
rebalgray
Specialist
Specialist
 
Posts: 45
Joined: Mon Feb 12, 2007 8:55 pm
Location: Crawfordsville, Indiana
Reputation: 0

Sponsored

Sponsor
 


Unread postAuthor: meatballs » Wed May 16, 2007 2:10 pm

one thing that gives a good fireball is if you put two layers of plastic wrap over the end of the chamber with a half cup or so of alcohol between them. fuel the cannon as usual, and the blast both vaporizes and ignites the alcohol. it makes a good fireball, three to four feet across, a bit larger than an exercise ball. its awesome. i haven't tried it yet, but gasoline would work too. it has similar properties to alcohol (like volatility) but the same amount has more energy so the same amount should give a bigger fireball.
  • 0

User avatar
meatballs
Sergeant First Class
Sergeant First Class
 
Posts: 146
Joined: Thu Jan 25, 2007 10:39 pm
Location: my house
Reputation: 0

Unread postAuthor: Pete Zaria » Wed May 16, 2007 2:19 pm

A few things:

1) Big muzzle flashes usually indicate an inefficiently high C:B ratio, or a much-too-rich fuel-air mixture.

2) Spraying anything down the inside of the barrel is a bad idea because it will continue to burn for a few seconds after the combustion process is over, and will gradually weaken the barrel. I've seen it happen.

3) Gasoline and PVC don't mix as far as I know. Since gasoline dissolves lots of polystyrene and polyvinyl products, I try to keep them separate, lol. It should be OK in ABS though...

4) Meatballs has it right, the best way to do special-effects type fireballs is by putting some fuel at the END of the barrel. I've done this by putting some paper towels soaked in alcohol or diesel in the end of the barrel (though I use ABS for my combustion guns so I don't worry much about the effects of solvents on the pipe). That works great. I'm sure his plastic wrap idea would be fine, too.

5) Loud bangs are best accomplished using burst disks and a short barrel. Propane is very loud when mixed properly. Engine starter fluid (usually contains ether) is the next best thing if you can't do metered propane.

Peace,
Pete Zaria.
  • 0

User avatar
Pete Zaria
Moderator
Moderator
 
Posts: 978
Joined: Fri Mar 31, 2006 6:04 pm
Location: Near Seattle, WA
Reputation: 0

Unread postAuthor: paaiyan » Wed May 16, 2007 2:32 pm

I've been wanting to experiment with powdered magnesium, but I'm not sure how easily it would ignite. If you could get it to work, you'd be rewarded with a very bright white muzzle flash. I mean blindingly bright, especially at night.
  • 0

"Who ever said the pen was mightier than the sword, obviously, never encountered automatic weapons."
-General Douglass MacArthur

Read my dog's blog - Life of Kilo
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: Pete Zaria » Wed May 16, 2007 2:36 pm

paaiyan wrote:I've been wanting to experiment with powdered magnesium, but I'm not sure how easily it would ignite. If you could get it to work, you'd be rewarded with a very bright white muzzle flash. I mean blindingly bright, especially at night.


It would be a lot of fun to build a small special effects cannon with a small-ish (say, 2" x 10") steel chamber, a half inch union for burst disks, and a few inches of half inch steel pipe for barrel. Setup a small propane (and/or oxygen.... :twisted: ) meter system.... You could load it with burst disks, put powdered magnesium, powdered iron oxide and aluminum, gas, whatever in the "barrel" and fire it. Having the combustion occur directly under the "secondary fuel" should ensure ignition. Especially using oxygen.

Wouldn't be too expensive either...

Peace,
Pete Zaria.
  • 0

User avatar
Pete Zaria
Moderator
Moderator
 
Posts: 978
Joined: Fri Mar 31, 2006 6:04 pm
Location: Near Seattle, WA
Reputation: 0

Unread postAuthor: paaiyan » Wed May 16, 2007 2:54 pm

Pete Zaria wrote:
paaiyan wrote:I've been wanting to experiment with powdered magnesium, but I'm not sure how easily it would ignite. If you could get it to work, you'd be rewarded with a very bright white muzzle flash. I mean blindingly bright, especially at night.


It would be a lot of fun to build a small special effects cannon with a small-ish (say, 2" x 10") steel chamber, a half inch union for burst disks, and a few inches of half inch steel pipe for barrel. Setup a small propane (and/or oxygen.... :twisted: ) meter system.... You could load it with burst disks, put powdered magnesium, powdered iron oxide and aluminum, gas, whatever in the "barrel" and fire it. Having the combustion occur directly under the "secondary fuel" should ensure ignition. Especially using oxygen.

Wouldn't be too expensive either...

Peace,
Pete Zaria.


Yea that would be pretty sweet. Of course, being a half inch barrel you could also load marbles, just so it could also be functional.
  • 0

"Who ever said the pen was mightier than the sword, obviously, never encountered automatic weapons."
-General Douglass MacArthur

Read my dog's blog - Life of Kilo
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: SpudBlaster15 » Wed May 16, 2007 8:52 pm

My metered propane combustion is disturbingly loud when fired with no projectile. Much louder than a 12 gauge shotgun. Not much for muzzle flash, though.
  • 0

People should not be afraid of their governments. Governments should be afraid of their people.
User avatar
SpudBlaster15
Major General
Major General
 
Posts: 2385
Joined: Wed Oct 18, 2006 11:12 pm
Location: Canada
Country: Poland (pl)
Reputation: 3

Return to Combustion Cannon Discussion

Who is online

Registered users: Bing [Bot], Exabot [Bot], Google [Bot], Google Adsense [Bot], MSNbot Media, Yahoo [Bot]

Reputation System ©'