My Mimi didn't scream

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edwardw

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I got a Screaming Mimi Kit at Hobby Lobby on discount and wanted to build it. The whistlers intriguied me. I put her together as per directions and flew her today. On the package and on the EMRR reviews they said she screams on a D12. So I thought, hmmm, I've got some F12's here. That should do the trick. Same impulse, longer burn. After a failed ignitor she flew, but no screaming was heard. I'm puzzled. Did my attempt to make her scream only cause those little whistles to 'stall' cause they were going too fast???? Any ideas?

Edward
 

Johnnie

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Even on the D12's, the Scream'n Mimi "scream" is actually just a little whine...at least the ones I have heard. The one I have seen fly on the F21 work horse, was just to over powered for the cheap little whistlers to be affective.

I am finishing my second Deuce, and I will start on my Mimi. I forgot I even had one :rolleyes:

I hope to get it to whistle on come E18's
 

nomopbo

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I have only ever flown my MiMi on D motors. The only time I can hear the whistle is when the burn is over and it coasts right before ejection. And it's not real loud at that. Yours just may have been so high and far away from you to even hear it.

Great rocket, one of my favorites.
 

billeblurzz

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Yeah that's right!!! You just had WAY too much motor to hear the Mimi! If you use a D12-5, you can hear a subtle whine after the motor burns out and the rocket is not too high and far away...kinda like a turbine winding down before the chute ejects!!! Really nice!:cool: :cool:
 

bsexton

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One of our members from the Vikings flew one this past Sunday and I was expecting to hear something like those whistling fireworks rockets -- nowhere even close. But it was a very nice flight...
 

firemanup

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What nomopbo said is what we've found to be true with ours also... just during the coast phase and only if it's not too far away...
 

nomopbo

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I did fly my MiMi on an Aerotech "E" a couple days ago. I was still able to hear the whistle during the coast phase. A bit to long of a delay, but still a good flight and still audible whistle.
 

moocrew

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I think it may be possible to modify it slighty and make the whistling tubes slightly longer?
i think it has something to do with how much air passes through it so longer tubes may mean more Scream?
I dunno seems like a good "try" atleast ;)
 

JeromeK

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The first one I ever saw/heard was pretty cool. Heard the sound all the way up on an E9. Now this was out in the middle of nowhere in Lucerne Valley, CA at one of the ROC monthly get togethers. But it's so quiet out there you can hear most rockets whistle (this is something I never was aware of!). I've wanted to get one. Then at the big ROCStock event a few weeks ago, a lot of folks had them, but few made noise.

I thought I remember seeing on the package that they only make noise on "E" motors. Hmm...



Jerome
:cool:
 

SpartaChris

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I upgraded mine to a 29mm motor mount, so I will let you know how it goes at the next launch I go to. I am also planning on adding a couple of scoops to the fronts of the whistle tube in an attempt to trap more air. Should be interesting...

-Chris

BTW. Anyone know the CP for this kit?

-Chris
 

shreadvector

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The instructions say it only makes sound on the D12 motors (not the C11 motors). It is not designed for the E9 (would need a longer motor tube and a spacer for the shorter C11 and D12).

The lack of sound is semi-common. It a result of different whistles with different manufacturing tolerences. Some whistle great, others get stuck when you blow too hard and stop making sound.

SO, overpowering them may not be the answer. You may need to do "whistle-triage" and select the best ones. Or you could try lubeing them with a super thin silicone spray. I have not tried that yet.

I'll have to try launching mine at Lucerne Dry Lake in late October. Should be great at 7am.



Originally posted by JeromeK
The first one I ever saw/heard was pretty cool. Heard the sound all the way up on an E9. Now this was out in the middle of nowhere in Lucerne Valley, CA at one of the ROC monthly get togethers. But it's so quiet out there you can hear most rockets whistle (this is something I never was aware of!). I've wanted to get one. Then at the big ROCStock event a few weeks ago, a lot of folks had them, but few made noise.

I thought I remember seeing on the package that they only make noise on "E" motors. Hmm...



Jerome
:cool:
 

Fishhead

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One of the guys I flew with today launched one. The whistling was drowned out by the noise the motor produced, but you could hear it just slightly as it coasted after burnout. It won't wake anyone up, but it's audible.
 

eugenefl

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Here's an idea - put a motor in it that'll take it high. Make sure the motor has an extra long delay - long enough for the Mimi to coast downward but not to the ground.

I've seen 2 SM's fly and both have had the post motor burnout "whine" that everyone here describes.

Anyone ever owned a Nerf whistle football? Now *those* make noise!
 

Hospital_Rocket

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Originally posted by eugenefl
I've seen 2 SM's fly and both have had the post motor burnout "whine" that everyone here describes.

Anyone ever owned a Nerf whistle football? Now *those* make noise!
I smell a kitbash!
 
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