How-To: Make your own model rocket igniters

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By Gareth Branwyn
Posted 2010/11/08 @ 2:46 pm
Category Fun & Games, Kids & Family

Over on our Make: Projects platform, our old pal Stefan Jones shows you how simple it is to create your own nichrome igniters for model rocket motors, using little more than nichrome wire, masking tape, and some lacquer paint, hobby dope, or nail polish.

How-To: Make your own model rocket igniters

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3 Responses to How-To: Make your own model rocket igniters

Giancarlo Todone on November 9th, 2010 at 3:53 am said:

i used to do stuff like this with items more easy to find:
+take the red heads off some dozens of matchsticks
+pour a drop of water and a drop of acetone (real acetone, not any nail polish) on the matchsticks heads
+SLOWLY and gently squeeze the mud you obtain until it’s uniform
+take a 1 ohm resistor (try not to take the fireproof kind, of course…) and paint it with the red mud you produced
+leave it dry

… now you have a firestarter that can be turned on with a 9v battery…

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RocketGuy on November 9th, 2010 at 12:13 pm said:

There are several types of ignitor that one can make oneself. My favorite was the ignitorman strip and dip kit. I don’t think it’s produced any more, but Magnalite apparently is similar. Essentially, you have a pyrogen that consists of a heavy “liquid” paste that contains both a pyrogen and conductive particles. This ensures maximum heat transmission to the pyrogen.

Two stripped wires that are parallel at a set distance are dipped into this stuff, completing the circuit between the leads. For black powder motors, you then dipped the ignitor into an acetone based clear-coat.
For the higher powered composite motors, there was a second layer of a different pyrogen added, and then clear-coated. This burned hotter to ensure ignition of the more difficult composites.

I made dozens of these ignitors, and unlike store bought, they worked every time, without fail, even after sitting for years in a few cases. Wire-wrap wire works great, a CAT5 pair can work too, but it’s a little thick.

But getting to my title, all the ignitors really work better when you’ve got a good power source, 12V or even 24V, and capable of sourcing a few amps. One of the 12V emergency jump batteries works fine, although I’ve seen some great capacitor-assisted systems too. (Although, that was for LUNAR’s multi-pad club launch system). And of course, for a long run to the pad, use heavier gauge wire to reduce power loss.

Happy skies-
-RG

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- StefanJ on November 9th, 2010 at 3:31 pm said:
  
  I bought the Igniterman kit, and made a few dozen igniters. They worked great! Much more reliable than the “Copperhead” igniters that Aerotech was distributing with its motors until a few years back.
  
  Note that the old-school nichrome igniters described in my article are strictly for Estes and Quest motors. You wouldn’t use those in an Aerotech or any other composite motor.
  
  By turn-about, unless you’re dealing with a special circumstance it is overkill to use a “dipped” igniter in a black powder motor. Especially with a 12v system behind it. I’ve used a dozen or so of my home-wrapped igniters this year and didn’t have a single failure. I save my Estes igniters for clustering and my occasional solo launch.
  
  The LUNAR launch setup I remember (1997 – 2002) was wonderful. Not just the launch panel, but the whole system. Pads, the posts and string around the permieter, the PA system. It went up quickly with the help of a dozen folks bribed by launch cards!
  
  Reply ↓