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 58 users online :: 5 registered, 0 hidden and 53 guests


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

Registered users: Bing [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

Planning to make a combustion.

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

Planning to make a combustion.

Unread postAuthor: )DEMON( » Fri Nov 24, 2006 3:31 am

I am planning to make my first combustion, I want it to be good. I have an pressure rated scrapped air chamber that I want to use for my combustion.
I am planning on getting a stungun or a camera flash ignition, most likely a camera flash. The ignition will be removable so I can use it for future cannons or for easy maintanance. The back of the camber will have a tee, the ignition will go at the bottom of the tee and the vent, with a chamber fan will go at the back of the tee. The chamber is 75mm wide, about 3 inches, I want to now the best chamber legth and best barrel size and length.

I am thinking about propane injection, as I have a huge tank of propane to use at my dispence. How do you rig one of those small propane tanks up to your propane metering system? I use them in my blow tourch but what fitting do I use to link it?

Any comments and segestions?
  • 0

Attachments
plans1.JPG
the chamber as planned.
plans1.JPG (13.66 KiB) Viewed 1269 times
IMG_0136.JPG
Blow tourch which uses small propane tanks. (or super gas- propane and butane)
IMG_0135.JPG
the air chamber, all pressure rated.
IMG_0133.JPG
The propane tank, not full but should be good for a few hundred shots.
Forever dreaming...
User avatar
)DEMON(
Major General
Major General
 
Posts: 1391
Joined: Sun Mar 12, 2006 1:22 pm
Location: Johannesburg South Africa
Reputation: 0

Unread postAuthor: rna_duelers » Fri Nov 24, 2006 4:31 am

Well there isnt a rule on what is the best pipe sizes to use,more so it is the ratios used on the combustion cannon.The opitmal ratio is rumord to be a .8:1 C:B ratio.

As for the propane injection.You do no the basics of propane injection?Dont you..Good so we can skip that part...For that propane tank is there a pressure reducer?A little disk shaped object,this lowers the pressure considerably and unless you want a metering system that is 1/4 the volume of your chamber then dont bother.
No doubt you have seen 1/4 NPT hose barb conectors.A simple way is to just cut the hose for you propane bottle(make sure its not turned on)and add the hose barb along with a hose clamp.Now you have NPT for your propane bottle and the rest is easy as the leg bone is connected to the knee bone the knee bones connected to the thigh bone etc..etc..

The ignition source that you have in mind will work but i find it very tempramentle and annoying.Those cameras always find a way to mess up and stop working when you least want it to.So depending were you live go with a stungun,lantern or even a BBG ignitor.But one of those cheap long nose ones and hook it upto a spark plug.Make the spark gap noticable bigger though.

Need anymore answers?Dont be afraid to ask.
  • 0

Image
User avatar
rna_duelers
Major General
Major General
 
Posts: 1740
Joined: Mon Sep 26, 2005 7:07 am
Location: G-land Australia
Country: Australia (au)
Reputation: 1

Unread postAuthor: )DEMON( » Fri Nov 24, 2006 4:53 am

I will do some more research on Burtnlatke about ratios. As for the propane injection, you mean I need a regulator for the big tank? I thought propane was always 90psi. I am not to sure what you are trying to tell me there.

"No doubt you have seen 1/4 NPT hose barb conectors.A simple way is to just cut the hose for you propane bottle(make sure its not turned on)and add the hose barb along with a hose clamp.Now you have NPT for your propane bottle and the rest is easy as the leg bone is connected to the knee bone the knee bones connected to the thigh bone etc..etc.. ", ???, is this for the small tank?

For the camera flash ignition, I am sure I have found the perfect flash, it is not from a disposable camera, it is an actual camera flash. I could make it reliable if I make a good job out of it. Look at the pics.

On the flash there is a red, black and thick white wire, whats the white one for?
  • 0

Attachments
IMG_0133.JPG
IMG_0134.JPG
IMG_0135.JPG
IMG_0136.JPG
Forever dreaming...
User avatar
)DEMON(
Major General
Major General
 
Posts: 1391
Joined: Sun Mar 12, 2006 1:22 pm
Location: Johannesburg South Africa
Reputation: 0

Unread postAuthor: rna_duelers » Fri Nov 24, 2006 5:35 am

I meant by the regulator that is usualy attached to them that reduces the pressure to like 7psi or something small like that.And i meant that for the propane injection for the metering system.Got MSN or something much easyer to explaine.
  • 0

Image
User avatar
rna_duelers
Major General
Major General
 
Posts: 1740
Joined: Mon Sep 26, 2005 7:07 am
Location: G-land Australia
Country: Australia (au)
Reputation: 1

Unread postAuthor: )DEMON( » Fri Nov 24, 2006 5:45 am

Nope, no Msn, sorry. Why do you need a regulator? On BurntLatke the propane metering systems are 90 psi, arn't they. Look here, you will see what I mean: http://www.burntlatke.com/jpg600/lp-test.jpg

I found my chamber fans and we have a big rechargable battery which is 12 volts, PERFECT! It is mean't for one of those tourches but it is spare. We also have a tourch which is not working so I can take the charging circuit out of there and use it for my chamber fans. This combustion is going to be impressive 8)
  • 0

Attachments
IMG_0133.JPG
Forever dreaming...
User avatar
)DEMON(
Major General
Major General
 
Posts: 1391
Joined: Sun Mar 12, 2006 1:22 pm
Location: Johannesburg South Africa
Reputation: 0

Unread postAuthor: jrrdw » Fri Nov 24, 2006 7:22 am

I could be wrong, but i think the white wire is to trigger the flash, (release the power from the capasiter).
  • 0

When life gives you lemons...throw them back they suck!
User avatar
jrrdw
Donating Moderator
Donating Moderator
 
Posts: 6539
Joined: Wed Nov 16, 2005 5:11 pm
Location: Maryland
Country: United States (us)
Reputation: 25

Unread postAuthor: )DEMON( » Fri Nov 24, 2006 7:42 am

How could I use it as an ignition?

You trigger the flash by pressing a little botton on the side.
  • 0

Forever dreaming...
User avatar
)DEMON(
Major General
Major General
 
Posts: 1391
Joined: Sun Mar 12, 2006 1:22 pm
Location: Johannesburg South Africa
Reputation: 0

Sponsored

Sponsor
 


Unread postAuthor: jrrdw » Fri Nov 24, 2006 8:03 am

Take the red and black wires and connect one to a screw and one to another screw that are screwed into your chamber. Have the screw tip be about 4mm apart in your chamber, push the button, and a spark should jump between the screw tips makeing the cannon fire. You should probly look up this kind of ignition on the spud wiki, mite be easier to understand.
  • 0

When life gives you lemons...throw them back they suck!
User avatar
jrrdw
Donating Moderator
Donating Moderator
 
Posts: 6539
Joined: Wed Nov 16, 2005 5:11 pm
Location: Maryland
Country: United States (us)
Reputation: 25

Unread postAuthor: )DEMON( » Fri Nov 24, 2006 8:23 am

I know how it works, I was just wondering about the white wire. So from what I understand it serves no purpose in my design what so ever. I think I will test the ignition soon. Thanks jrrdw.
  • 0

Forever dreaming...
User avatar
)DEMON(
Major General
Major General
 
Posts: 1391
Joined: Sun Mar 12, 2006 1:22 pm
Location: Johannesburg South Africa
Reputation: 0

Unread postAuthor: Bluetooth » Fri Nov 24, 2006 8:48 am

Watch this vid http://www.youtube.com/watch?v=-ErFr66Y0LQ. It explains everything about the camera flash stun gun. :D
  • 0

User avatar
Bluetooth
Brigadier General
Brigadier General
 
Posts: 863
Joined: Tue Jun 27, 2006 7:57 am
Reputation: 0

Unread postAuthor: mark.f » Fri Nov 24, 2006 9:17 am

Camera "stun guns", as I've seen them, don't create spark gaps. They use two contacts and when flesh contacts them, the charge is sent through the target.

For a spark gap that can jump more than .001", you need another way to rig the camera. For this, you need three wires, not two, as in standard ignition.

Two go to the ends of the flash tube, and these carry the +/- charge. A third goes the metal plate behind the tube. This one carries a strong + charge.

All three ends of the wire need to be connected to where they rest about less than a mm apart.

Then, charge the camera, and fire. Even before you press the trigger button, all the current is applied to the flash tube ends. If you touched them, you'd be fried. The wire from the metal plate ionizes the air between the end electrodes, and allows the current to flow when the button is pressed.

Believe me, I've experimented with this before. Never actually used it on a gun, (because it's a PITA to try and figure out how to wire dual gaps), but it's ultra-powerful and'll work great with your average hair-spray gun for igniting far-from-stoichiometric fuel/air mixes.
  • 0

User avatar
mark.f
Donating Member
Donating Member
 
Posts: 3464
Joined: Sat May 06, 2006 11:18 am
Country: United States (us)
Reputation: 21

Unread postAuthor: )DEMON( » Fri Nov 24, 2006 9:28 am

Ok, so that explains why I didn't get a spark when I tried to. So I will have to get a stungun, no problem, Christmas is coming :D

Camera flash has been done befor though, let me do some more research of wiki. After all, I did just cut the bulb and reflector out of my moms flash without asking.

I charged the capacitor in the flash and I don't think it is discharged yet, is that a bad thing? I do not want to get shocked.
  • 0

Forever dreaming...
User avatar
)DEMON(
Major General
Major General
 
Posts: 1391
Joined: Sun Mar 12, 2006 1:22 pm
Location: Johannesburg South Africa
Reputation: 0

Unread postAuthor: mark.f » Fri Nov 24, 2006 9:36 am

If it didn't discharge yet, get a screwdriver with a thick enough handle you'll trust, and touch the blade to the contacts. Get ready for a loud CRACK and any TV in your room to get an instantaneous fuzzy line down the center.

Just remember: DO THIS ALWAYS!!!!

Even with the three-poled igniter system, the capacitor never fully discharges. Drain that sucker every single time before you put the ignition system away. You might want to install a switch to do this for you, (a good one, mind you. :P ).
  • 0

User avatar
mark.f
Donating Member
Donating Member
 
Posts: 3464
Joined: Sat May 06, 2006 11:18 am
Country: United States (us)
Reputation: 21

Unread postAuthor: )DEMON( » Fri Nov 24, 2006 11:16 am

I have been looking at different means of ignition. More specifically the fly back circuit: http://www.spudfiles.com/spud_wiki/inde ... ck_circuit

A flyback circuit uses the flyback transformer from a TV or computer monitor to generate high voltage for ignition. It's one of the more complex ignitions to build, but the hot, continuous arc makes it very reliable.

The image on the right shows perhaps the most basic flyback driver that can be built. There are a few improvements that can be made though:

* Remove the 27Ω resistor, it gets very hot and also seems to limit the output voltage.
* Use a better transistor, the 2N3055 is not well suited for this.

I have the transformer it needs but I will need help putting the circuit together. Anyone want to help me?
I am kinda scared to touch the capacitor poles together, right now it is just sitting on the floor.
  • 0

Forever dreaming...
User avatar
)DEMON(
Major General
Major General
 
Posts: 1391
Joined: Sun Mar 12, 2006 1:22 pm
Location: Johannesburg South Africa
Reputation: 0

Unread postAuthor: SpudBlaster15 » Fri Nov 24, 2006 12:13 pm

I could go on all day about flyback circuits, but THIS page can do the talking for me.
  • 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

Next

Return to Combustion Cannon Discussion

Who is online

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

Reputation System ©'