4'' Igniters D21-E30 (6)

Many rocket flyers dislike this ignitor due to it's poor reliability. However, I have found that that poor reliability is usually a result of poor handling by the user. They are a bit fragile and must be handled with care. A common problem I see is use of alligator clips with teeth which can press hard enough to damage the insulation between the copper film and short the ignitor. A solution to that problem (if you do not have the Yellow Aerotech clip), is to separate the copper strands where they will then be hooked up like a normal two-wire ignitor. Do this by carefully holding a match or lighter to the end of the copperhead ignitor where the alligator clips will be attached (be very careful not to get the flame near the other end!). The insulation will melt just enough for the two copper strips to begin to separate. Then carefully pull the two ends apart just a little more. Take a piece of masking tape and run it along the inside of the Y that is formed by the separation. This will keep the ends separated and the two individual copper strips can be attached to the alligator clips like a normal ignitor. Finally, buy or make a small continuity tester and test your ignitor before installing in the motor. I actually prefer to use this method over the Yellow Aerotech clip, mainly because I usually forget to go retrieve my clip. However, if you are in a situation where you really need high reliability, get a First Fire Jr and save the copperhead for another day.