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

In total there are 30 users online :: 3 registered, 0 hidden and 27 guests

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

Registered users: Bing [Bot], Exabot [Bot], Majestic-12 [Bot] based on users active over the past 5 minutes

The Team
Global Moderators
global_moderators.png CS

Spark length calculation

A place to ask general spud cannon related questions.
  • Author

Unread postAuthor: mark.f » Wed Nov 29, 2006 6:59 am

Let's just go with this.

Spark gap is inversely proportional to the density of the gas. Since you're just doing a simple combustion, let's start you off at 1/8".

Also, in my experience, you need a larger, hotter spark to ignite unstoichiometric fuel mixtures. If you're using hairspray, lighter fuel, starter fluid, etc., I would lengthen the spark gap and increase amperage of the ignition source as well.

If you use metered propane, MAPP, or butane, you can probably make the spark smaller than 1/8", though. This is just because the mixture is more reactive, so you need less area and less work from the spark to ignite it.

You said you're a very exact person... so I'm sorry that all I can do is pull numbers and theories out of my ass. But, hey, they work for me.
  • 0

User avatar
Donating Member
Donating Member
Posts: 3531
Joined: Sat May 06, 2006 11:18 am
Country: United States (us)
Reputation: 26


Return to General Spud Cannon Related

Who is online

Registered users: Bing [Bot], Exabot [Bot], Majestic-12 [Bot]

Reputation System ©'