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steveh.jae

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Ah, I didn't know that! <Tom puts 1/14 2-stage NH on his "Hope to build someday" list>
So in that case I may just drill a hole, knot the string, and patch it up after the string test.... but yeah that is not easy...
It is a “thought experiment” for me at the moment, and when I relocate my NH (belongings boxed up for cross country move) I would prefer non-destructive tests to the Swiss cheese approach
 

Blast it Tom!

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Well, true... drilling is boring, anyway! ;)
I hope your move goes well. But what I was thinking of is getting the thing into flight trim, finding the CG by knife-edge balance, and then drilling a very tiny hole with a pin vice and using fishing line or fine wire for attachement to the string. I'm no fan of "holey" rockets either, but that's just a tough geometry to deal with. I'd be open to other suggestions as well.
 

steveh.jae

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Wish granted. You can choose 1/24 or 1/14 scale from Boyce.


Antares JS, do you know if Boyce has RocSim files for this rocket?
 

Ez2cDave

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That’s exactly my point! Please tell me how to ‘swing test’ the sustainer stage of the Hercules. I mean just look at it!! And the 1:14 scale 2-stage model IS indeed offered as an option.
Steve,

Here is a thought on how to Swing-Test the Upper Stage . . .

Make an "adjustable sling" . . . One end is passed through the "gap" in the Upper Stage Fins and tied securely around the Body Tube. The other end is tied securely to the Forward End of the Upper Stage in the "notch" formed by the Upper Fins, to keep it from slipping around.

The Sling is adjusted by making a loop and securing it with wraps of Masking Tape, to allow for adjustment, as Nose Weight is added. That will allow the rocket to be properly-oriented for the Swing-Test.

Dave F.

UPPER - SWING-TEST SLING - ADJ -2.jpg




UPPER SWING-TEST SLING DETAILS.jpg



SWING TEST - OPTION 2.jpg
 
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steveh.jae

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Steve,

Here is a thought on how to Swing-Test the Upper Stage . . .

Make an "adjustable sling" . . . One end is passed through the "gap" in the Upper Stage Fins and tied securely around the Body Tube. The other end is tied securely to the Forward End of the Upper Stage in the "notch" formed by the Upper Fins, to keep it from slipping around.

The Sling is adjusted by making a loop and securing it with wraps of Masking Tape, to allow for adjustment, as Nose Weight is added. That will allow the rocket to be properly-oriented for the Swing-Test.

Dave F.

View attachment 427878View attachment 427879
Thanks Dave. It will be an iterative process.
 

jrap330

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The Weight (I used BB's) were glued into place plus the weight is also sealed into the nose cone when you glue the shoulder section to the nose cone. I used different D12-5s for balancing also with the parachute and wadding, and one of those on this initial flight. I was playing with Open rocket and Rocksim but they don’t work with 3D printed parts, at least for a beginner like myself. At this point I’m thinking I should add more weight to the nose cone shoulder since that’s the most forward I can do now. Thanks for all the advice.
Sometimes it pays to go to the source instead of spit balling to the masses who may not be familiar with subject kit. Instruction say add weight until the CG is at the middle between booster and sustainer, right at the couplet before the upper fins and it fly stable on a D12-5. Any other motor run rock sim. So if your CG is at the middle and you use a D12-5 and she did aerobatics call Boyce and ask for assistance.. All missiles with "upper fins" have stability issues because fins move the CP forward......therefore added weight is reuired. It is hard to design a missile as a model rocket so call Boyce. Now since stability is marginal...only fly in low winds 0-5 mph.. And even thought over stable is frown upon..if your baby is unstable..YES add more weight.
 

steveh.jae

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Sometimes it pays to go to the source instead of spit balling to the masses who may not be familiar with subject kit. Instruction say add weight until the CG is at the middle between booster and sustainer, right at the couplet before the upper fins and it fly stable on a D12-5. Any other motor run rock sim. So if your CG is at the middle and you use a D12-5 and she did aerobatics call Boyce and ask for assistance.. All missiles with "upper fins" have stability issues because fins move the CP forward......therefore added weight is reuired. It is hard to design a missile as a model rocket so call Boyce. Now since stability is marginal...only fly in low winds 0-5 mph.. And even thought over stable is frown upon..if your baby is unstable..YES add more weight.
That addresses a single stage rocket, not a two stage version
 

lakeroadster

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Where's the launch lug? Typically those are placed at the CG. Maybe add another at the ideal CG, then use it for the swing test?
 

Ez2cDave

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Where's the launch lug? Typically those are placed at the CG. Maybe add another at the ideal CG, then use it for the swing test?
On the Booster, I believe, not the Upper Stage.

Dave F.
 

K'Tesh

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Does anyone know if model rockets were ever purposely designed to howl or whistle?
The "Lil' Augie" is designed to howl, the Estes Screamin' Mimi (2185) has whistles.

 

rcode

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The 1/24th scale version only comes as a single stage. Boyce doesn't have any open rocket or Rocksim files for these models. With the extra wight I started with (since I haven't adding any yet) the CG is forward about 1/4" just perfectly at the split of the large fins. With a new D12-5, wadding, and it's chute the rocket stayed nose 1st during the swing test this afternoon.
 

steveh.jae

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The 1/24th scale version only comes as a single stage. Boyce doesn't have any open rocket or Rocksim files for these models. With the extra wight I started with (since I haven't adding any yet) the CG is forward about 1/4" just perfectly at the split of the large fins. With a new D12-5, wadding, and it's chute the rocket stayed nose 1st during the swing test this afternoon.
WHY would Boyce NOT have RocSim files for these rockets? Are they not legit? Seems kinda low-rent, particularly since I just ordered the 2-stage version a couple of days ago. Maybe it’s stupid of me to think so, but I would think a company desiring to show how reputable they are would publish the RocSim files BEFORE they sold their product.
 

Ez2cDave

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Not every company provides Rocksim files for their models, do they ?

Dave F.
 

steveh.jae

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Not every company provides Rocksim files for their models, do they ?

Dave F.
I would expect the ones that charge $150.00 per unit to provide that HIGHLY, HIGHLY RELEVANT data. But maybe that’s just me, expecting the sun and the moon again. Don’t mind me, I’m in a particularly foul mood this evening.
 
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