Fireworks Circuit

[kybert]

I guess, but they are reusable and will do the job nicely.

 

[jpanhalt]

I guess, but they are reusable and will do the job nicely.

Are you sure they will ignite the fuse? Glow plugs are intended for use with methanol-containing fuels after compression of the air-fuel mixture, and the ignition involves catalysis by the hot platinum wire. I don't believe they will work with gasoline only. I have never tried pure gasoline, but the wisdom from a modelers site is that some methanol (e.g., 10%) must be present to use a glow plug for ignition.

Also, the coils get contaminated easily and cease working. Thus, even if they work initially, they may fail quickly.

Model rocketeers use electrical ignitions in the US. I don't know how widely available they are, but that might be a better choice for a one-time igniter. John

Edit: Here's a site with the igniters: **broken link removed**

 

[rangerdoc]

First of all: if you have a BATF license such as was mentioned in an earlier post, you can buy commercial e-matches for about $.25 each.
If not, 32ga nichrome wire is accepted practice, about 3-4 inches at most. You can also go buy model rocket ignitors from Wal-Mart. If you want the best, most reliable option, make your own e-matches from a kit. Skylighter.com sells the chips & compound (pyrogen) to make your own... nearly as good as commercial & cost just a few pennies each. They only require about 200mA @12VDC, but standard practice is to design for .5A for a single e-match; .9A for e-matches in series.
For my shows (I'm a licensed pyrotechnician), I use a pair of 6v lantern batteries in series. They've worked reliably for years. I just use a meter to short the terminals. If I get 2 or more amps, I'm good to go. I get them at Wal-Mart for $4/pair.