I still think it would have been much better and simpler to keep producing booster motors and skip the plugged motors. This whole business of plugging booster motors can be avoided simply by providing a port to vent the pressure, for those who don't want to plug the motor themselves. Estes could have done that on their rocket cars too.
Just another dumb Estes decision, I guess.
Ohh boy. In some rockets I don't have an engine block and wrap the back of the motor with masking tape as a thrust ring. Obviously a modification to the motor. Is it better I allow the motor to fly through the rocket?
Joel. phx
No, because gluing a thrust ring to a motor is one act that is specifically allowed by precedent and is hence not considered an alteration.
Those A10-0s certainly have a lot of destructive potential.
Yes. Always follow the rules and avoid installing adhesives anywhere along the motor. No tape thrust ring, no tape friction fit, no epoxy plug in the rear to lower flame output.
Jerry
Rules are rules. You can never have enough of them or fully descriptive enough ones.
Codify everything.
:-(
So it is written by BB (and nowhere else), so it shall be.
:)
The following contains worst case scenarios. It is not an attempt to predict that these scenarios are likely to occur. If it makes you feel better make believe I added a smiley face.
;-)
If the plug blows out (or if you use a non-plugged A10-0T) in a Rocket Car, it could set something on fire. It could be the car, it could be the stubble of dry grass, it could be the clothing of a spectator. Most likely nothing will happen. That is why Model Rocketry has been so safe, but there is still a real probability that something bad can happen. Flying Model Rockets have caused fires. Mostly when mis-used (NAR MRSC violated launching in the middle of dry brush, etc.). High Power Rockets have also caused problems (crashing though roofs of houses because they were launched on a site that was too small to 'contain' a ballistic impact within the launch and recovery site, crashing onto/into little league fields (same reason), etc.).
Of course, the home-made plug could fail as the pressure gets nice and high, turning it into an epoxy bullet that will shoot into an innocent child's eye (or MAYBE through their eye and into their BRAIN).
It's fun until someone loses an eye.
-Fred Shecter NAR 20117
-- ""Remove "zorch" from address (2 places) to reply.
are
An Estes ceramic plug is more likely to blow than an epoxy plug.
Unless your vent is upward.
Best to hide in your bedroom glued to TV or a video game just to be safe.
Demonstrating a total lack of understanding of BP motors to begin with.
Probably less hazardous than those Shecter Rockets hardwood nose cones which are actually on the OUTSIDE of the rocket already, ready to attack on a moment's notice that innocent child's eye with any normal or abnormal operation of the NAR approved, legally flown, model rocket.
Run around the house with scissors. It trains you for having fewer "accidents" that might poke your eye out.
Gee I wonder why I don't hang out with Fred Shecter anymore? He is like this in person as well gents.
Jerry
Specifically, S&T test notification #63 says that "...gluing something (such as a thrust ring) to the EXTERNAL surface of a rocket motor casing. We find that this does not modify the motor case and so long as it does not modify motor performance, this does not violate the NAR safety codes."
(emphasis on EXTERNAL is mine).
Therefore, it could NOT in theory extend to plugging booster motors with epoxy, since this is not gluing something to the exterior surface.
In my opinion, it seems that Jerry is 100% wrong.
-Fred Shecter NAR 20117
-- ""Remove "zorch" from address (2 places) to reply.
The back of a propellant charge and the ID of the case near the propellant charge of a BP SU motor is an external surface. It can be douched by directly touching a straight cylindrical probe from the top of motor direction.
You will note that no plug is assumed to modify motor performance. Not a clay one ove rthe propelling charge, not an epoxy one over the propelling charge, not even aplastic one in the nozzle where "modifying the performance" is all but assured.
Jerry
through their
You'll put your eye out, kid.
through their
Or MAYBE even through their eye, through their brain, then through a cute little puppy's eye AND their brain, then into a busload of NUNS and ORPHANS causing it to EXPLODE in a horrible fiery ball of death!
So is there a reason people don't tape the motor in against a bulkhead in the rocket/car?
Joel. phx
:)
"BB" wrote in news:eg16b.182$ snipped-for-privacy@nwrddc02.gnilink.net:
So a cap could be attached to the (external) front of the motor?
One could argue that plugging a motor, regardless of the cleverness of the technique, necessarily alters the performance of the motor, specifically what happens when the last web of propellant blows through (or would have blown through) at burnout.
len.
Kurt Kesler wrote in news: snipped-for-privacy@news-east.giganews.com:
Especially with that pointy stick!
len.
turning it
through their
What about it, Punk?
-Shread Vector NRA #1 Paramount Leader
-- ""Remove "zorch" from address (2 places) to reply.
Or that burning point stick.
-Shread "Don't get Punk'd" Vector NRA #1 Paramount Leader
-- ""Remove "zorch" from address (2 places) to reply.
Whatever the plugging methodology. Even wood glue would work.
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