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Homemade Rocket Ignitor

Homemade Rocket Ignitor

Homemade Rocket Ignitor

(OP)
To ignite my rocket engine, a thin wire folds up into the insides of the engine and when headed with a power source it will burn out the engine and launch.

________
engine  |   /------
      o=====           <-Ignitor
        |   \______
---------


Theres a cheap drawing of it, the two wires on the right are where the circuit connects to heat the wire. the "o" is some sort of material that burns easily when the wires are heated.

What im using:
I have a 6v battery for a power source and 18 guage copper wire to hook it up using alligator clips to the battery and open connection to the ignitor.

________            v-- splice        
engine  |   /------x-----------------------^ <-alligator
      o=====                        /--<8__8       clips
        |   \______x_______________/    |   |  <-6v battery
---------                               |___|


Problem:
Ive been testing with a match to see if a thin filament of copper wire would heat up and light a match. Thing is, it only works when the 18guage copper wire is about 1-2 inches long, if i get some wire about 12 inches long the match wont light, i then feel the copper filament and it seems its not getting as hot.

Question:
Using 1 foot of 18 guage copper wire on each battery prong, how can i keep the thin filament of copper wire hot enough to light the match (meaning its hot enough to light the rocket engine).

RE: Homemade Rocket Ignitor

You can't.  You should use two pieces of 14guage up to, as close as you can get, to the igniter.  Otherwise you are limiting the current and that warms the whole wire up instead of just the one thing you need to heat.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Homemade Rocket Ignitor

(OP)
ah ok, i understand now, it was the fact that my wire was too small for the current i needed.
thank you very much for the info and the quick reply

RE: Homemade Rocket Ignitor

(OP)
I like to provide solutions once i get something right so here ya go.

The solution to the problem, if anyone is seeking for such:
rather than using a thin filament of copper, use a thin filament of steel. Just in case, when i say filament, im referring to one of the twisted pieces of steel that makes up a steel rope or any similar item. I have heard of steel wool being used as well. Only use steel for what you want to burn. Use copper for the actual wire. Now, you have to take caution because after a few seconds if you dont switch off or disconnect the circuit, the steel will liquidate and burn stuff (bad). Keep a hand on the switch to quickly turn it off once the steel gets red, there is only about 5-7 seconds after you turn it on before it gets red.

Reminder, this such test is for lighting a match to make sure that igniting the rocket will work. In a full-scale run, the actual ignitor is plugged inside the engine and you wont need to use a steel filament, you just directly connect your power source to the two ignitor prongs sticking out of the engine.

qeustions/comments: alakatarato@gmail.com
im not a circuit genious at all, i just know how to launch a homemade rocket :P

RE: Homemade Rocket Ignitor

I used to use a light gauge wire up to about 1/4" from the igniter and then used a segment of one of the 'fine' wires from regular 110 Volt cord.  I would solder the fine wire in place and bend it through 180 degrees making sure it and the light gauge wire were electrically separated.  I then dipped the assembly in 'candy' aka sugar and saltpeter.  This worked really well.

Dik

RE: Homemade Rocket Ignitor

You could use steel wool. I see demonstrations where it will ignite at the voltages you are talking about. The best options are Tungsten and Magnesium. Tungsten can be a little had to come by in the quantities that you are interested in. Magnesium is sold in block form at most camping stores. Use a pen knife to slice off a small strand.   

RE: Homemade Rocket Ignitor

Guitar strings also work well for this application.

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