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  #11  
Old 09-17-2007, 06:38 AM
Rocket Doctor Rocket Doctor is offline
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Quote:
Originally Posted by Solomoriah
I have a dowel, 3/8" I think, in my range box; I painted it flourescent orange so as not to lose it in the grass. I use it mostly to push wadding into narrow body tubes (as my fingers are a bit thicker than they used to be...) but it is long enough to drive out friction-fitted engines. I disagree with RD, though... I push them out with slowly increasing steady pressure, holding the body tube carefully to avoid damaging it, and have always had good luck getting them out.

I launched my Bullpup a few weeks back; I wrap tape in a rough spiral starting at the upper end. I put a single wrap on, and try it in the engine tube; if I can push it 3/4 in and pull it out again without difficulty, I put a second layer on; generally, that layer involves less tape. I'm not covering the entire engine, I'm just laying down some tape to make it stay in.

I guess it really takes practice to get it figured out...



Going back to the "Good Old Days" when everything was friction fitted, there really wasn't any particular method for getting motors out.

If the motor protruded at least a 1/4" from the end of the body tube,generally, you could use a pair of pliars or vice grips. But, uf the motor is flush, the dowel method would be a choice. Either tapping (gently) or pushing, the bottom line is the removal of the motor.

Also as noted, you need to gently hold the rocket as well, not to damage the body tube or any items located on the tube body.

Also, I have noticed, depending upon which brand of masking tape used, after flight, the tape may be "sticky" due to the motor heat, in this case, after recovery, I would wait until the motor cools down before trying to remove it.

As pointed out, the Baby Bertha would have been a better choice in this case for a "to build" rocket and is very popular with svhool groups as well as scouts and 4-H'ers.

The bullpup is a great looking rocket, but, with you time restraints, your going to pressed for time.
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  #12  
Old 09-17-2007, 08:31 AM
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Shreadvector Shreadvector is offline
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The bullpup has had problems. The original version had only half the nose weight required for stable flight and this resulted in unstable flights and FIRES when the buring rocket hit the ground.

I notified Estes and they fixed the problem by doubling the nose weight and updating the instructions by adding a slip of paper warning you to add the extra weight.

When the launchables version first appeared in Wal-Mart several years ago, the first batch DID NOT have the extra nose weight! I called Estes to let them know and it was fixed on future production runs, but I don't know what the current instruction sheet says.

I DO know that the OLD version of the instructions posted on the original message in this thread are OLD and INCORRECT (and potentially dangerous - remember the "FIRE" hazard). They are the original instructions before the extra clay was added. Hopefully someone can update those instructions with the extra clay warning.

And those old instructions do show adding masking tape for a fristion fit of the motor. It is fairly clear in those instructions. Again, I don't know what the modern instructions say....

One additional warning (OK, maybe 2 additional warnings):

1) If the glue on the motor mount is not good and strong, when you install the motor with a friction fit, it may rip the motor mount tube from the centering rings or the centering rings from the main body tube.

2) If you do not have the motor block installed correctly and the motor sticks out the back of the rocket too far, it will be unstable and dnagerous. If you find this problem, either dig/tear out the motor block and reglue it in the correct position or retrofit with a mini-motor mount and only fly with A10-3T motors.
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  #13  
Old 09-17-2007, 12:36 PM
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Solomoriah Solomoriah is offline
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I did notice that the instructions for my Bullpup show an engine hook in some of the drawings; I wonder if it was originally planned but dropped due to the added difficulty of notching the tail cone.
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  #15  
Old 09-17-2007, 12:53 PM
Rocket Doctor Rocket Doctor is offline
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The instructions for the Bullpup have not been updated, and, by placing slips of updates in the kits suggests that they aren't going to update them anytime soo.

I had discussed this in length with the former marketing manager (who is no longer there) about updating not only the Bullpup instructions, but all outdated instructions.

It would be a great undertaking, but, should be done.

Also, depending upon who outlined the unstrucyions, you can tell by the format.

I had done many instructions, the two stage Renegade being my best.

Also, there could be a variety of Bullpup kits from different production runs and years still out there.
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  #16  
Old 09-17-2007, 01:02 PM
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Shreadvector Shreadvector is offline
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Quote:
Originally Posted by Rocket Doctor
The instructions for the Bullpup have not been updated, and, by placing slips of updates in the kits suggests that they aren't going to update them anytime soo.

I had discussed this in length with the former marketing manager (who is no longer there) about updating not only the Bullpup instructions, but all outdated instructions.

It would be a great undertaking, but, should be done.

Also, depending upon who outlined the unstrucyions, you can tell by the format.

I had done many instructions, the two stage Renegade being my best.

Also, there could be a variety of Bullpup kits from different production runs and years still out there.


Which is why all clubs with libility concerns need a "Safety Advisory":

http://home.earthlink.net/~mebowitz/safety.pdf
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  #17  
Old 09-17-2007, 01:13 PM
Rocket Doctor Rocket Doctor is offline
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Quote:
Originally Posted by Shreadvector
Which is why all clubs with libility concerns need a "Safety Advisory":

http://home.earthlink.net/~mebowitz/safety.pdf



The kit instructions need to be CORRECT from the start !!!!
This is how I got involved with instructions in the first place and found many things that needed to be changed.

A slip of paper could get lost or, not even noticed, if the instructions are WRONG they should be changed immediately, for the sake of a couple of pennies, is it worth it.

Also. group leader should be familiar with rocket building and the NAR safety code followed.

I have done many rocket building sessions where tje kids say "I know what I am doing" won't follow the instructor or read the instructions, and when their rocket doesn't look quite like the package or doesn't "work right" they are discouraged and don't want to conyinue in the hobby.

It's the "instant gradification" that has resilted in RTF's. Some good old building techniques with the parents participating is what we need.

Prototypes can't be tested enough as far as I'm concerned, if the release date needs to be extended, so be it, work the bugs out first, then release it.
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  #18  
Old 09-18-2007, 09:51 PM
BatPlane BatPlane is offline
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Quote:
Originally Posted by A Fish Named Wallyum
Didn't this rocket require nose weight?


Yeah, it does...we made one and packed the nose with the clay. Still haven't test flown it yet. The big test is this Thursday....
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  #19  
Old 09-18-2007, 10:04 PM
BatPlane BatPlane is offline
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Default Bull Pup Stability

Awww, man...Guys, I was feeling good until I re-checked the board just now. The Bull-Pup has stability issues?

I was wondering what the deal was with the clay. As I recall, we put it all in there & it's pretty top-heavy.

We'd better test fly that thing. Oh well....we've got 11 total Bull Pups. They look cool, they're going to be assembled this Thursday...now, I just hope we don't impale somebody or start a fire with 'em!!!!!
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  #20  
Old 09-19-2007, 07:51 AM
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Solomoriah Solomoriah is offline
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If you use all the clay, the Bullpup is plenty stable. I recommend a B engine for first launch, though, as it is a pretty heavy model.
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