Apparently, pushing a round toothpick in a round MMX nozzle could lead to overpressure and possible explosion of a Micro Maxx engine. The toothpick shouldn't be crammed in like a plastic igniter plug used in 18mm or larger engines.
In an earlier post (click HERE) I wrote of my success using a square toothpick (instead of a round one) to hold the igniter in the small MMX nozzle. The square toothpick might allow some pressure to escape and prevent an engine CATO. Picture a "Square peg in a round hole".
Some posts agreed that square toothpicks could be the way to go with igniter installation in MMX engines.
If using a toothpick to hold in an igniter in a Micro Maxx engine, don't force the toothpick into the nozzle!
Insert the igniter far enough into the nozzle so it touches the propellant. Set a toothpick into the nozzle - don't force it in!
Once slid down the launch rod, the toothpick rests on the blast deflector. The weight of the rocket on the toothpick should be enough to hold the igniter in the nozzle and guarantee ignition.
I've only used toothpicks a couple of times and didn't experience a CATO. The only CATO I've had on a MicroMaxx was in a flash pan set up, where the nozzle blew out. Your rationale for a square toothpick makes sense to me. Nowadays, I just bend the igniter leads outward a bit, bend them at a 90 degree angle and let the weight of the rocket hold it in. I use masking tape on the deflector as required to keep it form shorting them. I have about a 80+ success rate using the newer stock igniters and then use Estes igniters for the rest, picking the ones with a thin pointy tip.
ReplyDeleteBTW, I like your new banner.
Hi Dick,
ReplyDeleteI haven't had a misfire on the MMX engines since the newer igniters came out. I came by the square toothpicks by accident. They seem tohold the igniter in better until I get it down the launch rod, then the weight of the rocket takes over.
I'll change out the banner on occasion, that font fit the spray cans in the picture and Halloween coming up.
Thanks, Chris