Mini Comanche 3 Build Question?

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TangoJuliet

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I recently returned to the hobby after a few decades away from it, and one of my recent build projects is the Estes Mini Comanche 3. Normally I could throw a simple model together without even referring to the instructions, but this one has me scratching my head a little, and the instructions aren't real clear.

In the kit are three yellow tubes cut to represent 1/2A motors for the purpose of locating and installing the motor thrust ring in the sustainer, but it also appears that there is a thrust ring to be placed at the aft end of the 1st stage booster? Almost like a retaining block. I've never seen this before. And if I mount everything as it appears the instructions are telling me to do, then the thrust ring in the sustainer is too far forward. Can anyone shed some light on this for me? I'm very confused.
 

Charles_McG

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The aft engine block is a multistage-thing. When the second stage engine lights up and pushes against the 1st stage, the aft engine block retains the motor, so the whole stage gets pushed away, rather than spitting the motor casing out the back and burning up the 1st stage motor mount.

Go on, ask me how I know :)

I suspect that the second stage retention is just friction.
 

TangoJuliet

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That makes sense. I'm at work until late tomorrow night, so I'll have another look at it on Thursday morning again.
 

Micromeister

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The aft engine block is a multistage-thing. When the second stage engine lights up and pushes against the 1st stage, the aft engine block retains the motor, so the whole stage gets pushed away, rather than spitting the motor casing out the back and burning up the 1st stage motor mount.

Go on, ask me how I know :)

I suspect that the second stage retention is just friction.
Excellent explaination! and right on. Long before Estes decided to kit the Mini-Comanche-3, I down scaled a Comanched-3 model to 13mm, I called it the Mini-Manche-3. While all stage motors were friction fit, the sustainer did have a thrust ring. In my version I didn't use the aft thrust ring but if a had to build it again I'd add one as it is a great way to ensure the first stage booster seperates from the stack.

Using A10-0T, A10-0T to A3-6T the sustainer of this little model was out-of-sight most of the time after the first stage boost. Took a lot of people with eyes to the sky a long time to catch the sustainer streamer coming down almost 2 minutes after lift-off. 1/2A-4T is a better choice for the sustainer motor. Now I only fly the model on some Oop A3-0T boosters as well. Even with the lower thrust booster this 3-stage model really gets a lot of altitiude. Hope you have a very large recovery field:)
 
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Charles_McG

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You mean this OOP Centuri B4-7 I have sitting here might not be a wise choice for the sustainer?
 

TangoJuliet

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I'm trying to recall from memory, but I think the sustainer thrust ring is mounted too far forward by maybe 1/4". It seems to me that I recall there being some play when I stacked all three of the yellow tubes to check the fit of everything after gluing in the sustainer motor mount. :facepalm:
 
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