Help with Quest Zenith II kit

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JWIII

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As inexperienced as my son and I are, we did a pretty good job with assembly. Now a problem...Through a gluing faux pas, the bottom stage could not be seated fully into the bottom of the main rocket body. I've managed, with an exacto knife, to meticulously shave away the glue drip blocking the way. Problem not quite solved: the path is clear but it is an extremely tight fit, so tight that i don't believe the bottom stage will eject. Being inexperienced with this rocket brings out several questions. 1. Is the bottom stage supposed to come off in flight? 2. If not, why doesn't the second motor blow the rocket apart being there isn't a clear path for the thrust. 3. If the bottom stage is supposed to fit looser, what can I do to make it fit better? 4. How loose should it be? I'd love to ask other questions but these are the most important at the moment, so baby steps.
 

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BEC

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Yes they are supposed to separate. You either need to reduce the outer diameter of the stage coupler on the booster (sanding) or the inner diameter of the upper stage where they join. It's a lot easier to work on the booster, since the stage coupler is exposed, so that's where to work the fit issue.

How loose it needs to be is kind of hard to describe. It should slide apart fairly easily, but not just fall off if you hold the model in flight attitude.

As I recall in building one of these, the fit, even without excess glue, was pretty firm before sanding the coupler down a bit.
 

JWIII

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Bernard, Thank you for your expertise---excellent response! If you don't mind an amateur asking another question: Although it may become evident as I continue assembly, how exactly does the second rocket motor ignite? I know the first stage uses an igniter attached to the battery pack. Does motor 1 ignite motor 2?
 

BEC

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Yes. You use a booster motor in the first stage: one with a -0 listed for the delay (A8-0, B6-0, C6-0). These don't have a delay or ejection charge. As a booster motor nears burnout the upper wall of propellant bursts and flaming bits go shooting out the top, toward the nozzle of the upper stage motor. These start the second stage.
 

JWIII

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Wow, sounds almost mystical, but I know it is science. I'd better check my motors to be sure I have the right ones. Thank you again for the knowledgeable and rapid response!
 

neil_w

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You may find the following video to be interesting. It shows pretty conclusively that it's hot gas and flame emitted from the booster motor that lights the sustainer, not flaming bits.
 

BEC

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Thanks for that, Neil. Either way....the stages need to stay together long enough for the sustainer to get lit, but not too long, hence the initial concern about stage-to-stage fit.
 

JWIII

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Thank you for the video, Neil, and again to you Bernard. So far the sanding is working. I'm going slowly and meticulously as to not over do.
 

JWIII

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Hello,

For my Zenith II rocket it is recommended that I use motors B6-0/A6-4. I know one motor ignites the other. Does the booster motor power the 2nd stage? The B6-0 is labeled the booster motor. Is that correct? And just to be sure, is the A6-4 the one on the bottom, the motor that is ignited first? Basically what positions do I place the motors? One other problem I’m having is the hobby store sold me an A8-3. Should I try to acquire an A6-4 motor. Thank you so much for your help. The instructions are just not detailed enough and I don't want to guess.

Joe,
Still trying to finish and launch after several months
 

TigerHawk

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Hello,

For my Zenith II rocket it is recommended that I use motors B6-0/A6-4. I know one motor ignites the other. Does the booster motor power the 2nd stage? The B6-0 is labeled the booster motor. Is that correct? And just to be sure, is the A6-4 the one on the bottom, the motor that is ignited first? Basically what positions do I place the motors? One other problem I’m having is the hobby store sold me an A8-3. Should I try to acquire an A6-4 motor. Thank you so much for your help. The instructions are just not detailed enough and I don't want to guess.

Joe,
Still trying to finish and launch after several months
A6-4 motor is a old Quest bp motor that is not being made anymore. The Estes A8-3 motor would be good to use I believe. Use the B6-0 (booster motor) in the first stage and the A8-3 in the second stage (main rocket).
 

neil_w

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For my Zenith II rocket it is recommended that I use motors B6-0/A6-4. I know one motor ignites the other. Does the booster motor power the 2nd stage? The B6-0 is labeled the booster motor. Is that correct? And just to be sure, is the A6-4 the one on the bottom, the motor that is ignited first? Basically what positions do I place the motors? One other problem I’m having is the hobby store sold me an A8-3. Should I try to acquire an A6-4 motor. Thank you so much for your help. The instructions are just not detailed enough and I don't want to guess.
The motor in the "bottom" is the booster or 1st stage motor. That's where you use the -0 delay motor, as it is designed to ignite the next ("2nd stage" or "sustainer") motor.

Estes B6-0 in the booster and A8-3 in the sustainer should be fine.
 

BEC

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Joe (@JWIII ) — Those of us who have been in this game for a long time (or started long ago and came back, like me) remember Estes Industries TR-2 about multi staging, which goes into all sorts of detail which should help. It is available in this currently-online publication: https://estesrockets.com/wp-content/uploads/Educator/2845_Classic_Collection_TR-TN.pdf

That said, the Zenith II, if I recall correctly, does NOT use directly taped-together motors, but has motor hooks for each of them and actually has a small gap between the motors as installed in the stages. This is OK, but this is also the reason why you don't want the stages to separate too easily.

As others of noted, the A8-3 should be in the second stage ("sustainer") and the B6-0 should be in the first stage ("booster") — the one on the bottom.

Personally, in that model, using an Estes A in the upper stage I'd be torn between an A8-3 and an A8-5. The delay on the former will likely be a bit short, so the 'chute will be deployed while the rocket is still coasting upward. But it shouldn't be too short as to cause any damage.
 
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neil_w

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One other suggestion: fly it the first time or two (or three) without the booster. Use an A8-3 or B6-4 in the sustainer and fly it as one stage. A lot more can go wrong with 2-stage flights, so it's good to get in some "safe" flights before going two-stage. Especially given your lack of experience.
 

JWIII

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A6-4 motor is a old Quest bp motor that is not being made anymore. The Estes A8-3 motor would be good to use I believe. Use the B6-0 (booster motor) in the first stage and the A8-3 in the second stage (main rocket).
Thank you, TH, for clearing that up. I am confident, now, that the motor I have will work.
 

JWIII

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The motor in the "bottom" is the booster or 1st stage motor. That's where you use the -0 delay motor, as it is designed to ignite the next ("2nd stage" or "sustainer") motor.

Estes B6-0 in the booster and A8-3 in the sustainer should be fine.
Neil, thank you! This really clears up the positions of the motors for me. Gets me closer to my goal.
 

JWIII

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Joe (@JWIII ) — Those of us who have been in this game for a long time (or started long ago and came back, like me) remember Estes Industries TR-2 about multi staging, which goes into all sorts of detail which should help. It is available in this currently-online publication: https://estesrockets.com/wp-content/uploads/Educator/2845_Classic_Collection_TR-TN.pdf

That said, the Zenith II, if I recall correctly, does NOT use directly taped-together motors, but has motor hooks for each of them and actually has a small gap between the motors as installed in the stages. This is OK, but this is also the reason why you don't want the stages to separate too easily.

As others of noted, the A8-3 should be in the second stage ("sustainer") and the B6-0 should be in the first stage ("booster") — the one on the bottom.

Personally, in that model, using an Estes A in the upper stage I'd be torn between an A8-3 and an A8-5. The delay on the former will likely be a bit short, so the 'chute will be deployed while the rocket is still coasting upward. But it shouldn't be too short as to cause any damage.
BEC, you are correct, and getting those hooks into place wasn't easy - I just hope I positioned them correctly. Thanks for providing additional confidence regarding the motors' position and the A8-5 info. I'll trust the A8-3.
 

JWIII

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One other suggestion: fly it the first time or two (or three) without the booster. Use an A8-3 or B6-4 in the sustainer and fly it as one stage. A lot more can go wrong with 2-stage flights, so it's good to get in some "safe" flights before going two-stage. Especially given your lack of experience.
One other suggestion: fly it the first time or two (or three) without the booster. Use an A8-3 or B6-4 in the sustainer and fly it as one stage. A lot more can go wrong with 2-stage flights, so it's good to get in some "safe" flights before going two-stage. Especially given your lack of experience.
Thanks, again, Neil. While I will consider your suggestion, this long awaited launch begs to be two stage. It's really too exciting to put off - I hope I don't regret it.
 
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