AeroTech Hobbyline RMS Assembly Diagrams, Videos

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rocketguy101

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In response to this thread , I have modeled the AeroTech 18/20, 24/40, and 29/40-120 motors with a CAD program to create cross sections and exploded views that will supplement AeroTech's instructions. I played with the "animate" feature of the CAD program (SolidWorks) to create videos of the assembly process.

All of my references came from the AeroTech website. Their "Resources" page is very handy and contains lots of information if you haven't visited it before.

Enjoy!
 
BTW a couple items I have gleaned from reading various threads on these reloads that I want to share here...

Something to remember with ALL Aerotech RMS loads, be it hobby or High Power. Always, I repeat ALWAYS make sure the forward closure is on all the way. If the rear does not go all the way thats not a big issue, as long as you seat it as far as it will go. This comes from Gary R personally several years ago. I have found that if I tighten the forward first, and then the rear they will usually seat properly. I have no blow-by issues...ever.

from this thread regarding the ejection charge after the cap is applied (not shown in my renderings)...

I had the exact same thing happen with the same case/load. Killed my first Interceptor E. I have to agree with the assesment of the powder not seating all the way down in the well. On mine I assembeled and loaded the motor in the rocket but was unable to launch for a couple hours. In that time it was turned in every direction one can imagine (my then 9year old engaging the enemy at warp speed). I failed to point it up and tap it to ensure proper seating of the powder and it met it's demise in the manner you've described to the letter. Since then I always give the lower end of the rocket a couple taps/knocks to be sure the powder is seated and have not had a repeat of the problem. I won't say for sure that was the problem but the results do seem to support it. FWIW

finally from several posters, go light on the grease for the o-rings and keep it off the propellant and delay grains!
 
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The biggest problem I have with the Hobbyline set of motors is the instructions clearly state to build it with the igniter installed but most clubs won’t allow you to do that.
 
The biggest problem I have with the Hobbyline set of motors is the instructions clearly state to build it with the igniter installed but most clubs won’t allow you to do that.
Yeah, I can usually slide one in after assembly, but I ran into the problem once of an igniter popping and not lighting the motor. I pulled it out, and the replacement(s) did not fit through the nozzle :eek: I tried a couple Copperheads, some Sure Fires, and some Estes PSII igniters...all them had an extra-large pyrogen blob!

I gave up and brought the motor home, unscrewed the retainer, and gently pulled the nozzle out taking care to not touch the o-ring and knock the ejection cap off. I inserted the igniter and re-assembled the motor. It successfully flew at the next launch. Later I read here on one of the igniter threads that you can scrape some of the extra pyrogen off in order to get the igniter fit through the assembled nozzle. Since I bought one of the AeroTech igniter clips from Hobbylinc, I have not had any Copperhead misfires.
 
^^-- Not much worse than single use, although it would be nice if there was a little table or something out on the range rather than having to leave all helpful work aids behind.

With the 24/40, I think I'm using the case tube backwards (not that it matters), but I align the grain slot with the thick line on the outside to make it easier. Doesn't work with the 29s though because the grain rotates when tightening the aft closure.
 
At my TRA level 1 cert, the other flyers backed by a range officer had a long winded serious story of a high powered rocketry L-3 , M-class motor with igniter inserted away from a flight line launch pad knocking out a section of a wall of a motel from inside a room. I do not think that group of people were talking crap. A flyer with his wife were able to tilt the motor away from themselves or other people nearby as it ignited. No igniters were near our HPR models on the bench with motors fully assembled in full view. Beyond the flightline the RSO held my igniter with my rocket on the pad, until it was time to connect the igniter to his electronic launch clamps, and at that point I had permission to insert the igniter into the casing and coil the wire around the clamps. It is something TRA takes seriously and after that story, I don't have a problem with them taking an extra safety measure to reduce risks.

A low power motor wouldn't have the damage involved, but you could still reduce risks of it igniting by keeping igniters away until it is ready to fly. Or another way would be build it with the RSO next to you at the pad if its easy and quick to build, because you are allowed to handle the igniter at that point if you were limited to TRA events.
 
Actually only TRA clubs prohibit it. NAR permits it for model rockets.

Tripoli prohibits inserting igniters in high power motors except at the pad and with the rocket pointed away from people. Because Tripoli has no model rocket safety code we don’t actually prohibit the practice in model rockets.
Nevertheless, we fully support local Prefectures who implement such a rule.
 
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Should the motor starter be connected to the launch pad leads before inserting into the motor? I observed someone do that under the premise that the launch system may have the inadvertent ability to set off an igniter. I use ematches, and have never had an issue. I arm the electonics, wait for them to reach launch ready status, then insert and connect the igniter.
 
I have always done same as you but at a recent launch, I observed several flyers connecting igniters before inserting into motor for same reason you mention. Guess it really depends on launch system?
 
If a launch system could inadvertently set off an igniter, I'd rather it did it when my hands were on the clips as opposed to directly beneath the throat. Untwist & connect is going to stay last for this ten-fingered human.
 
The launch system leads should never be connected to an inserted igniter until the rocket is on the pad and vertical and any recovery systems have been armed.

From NFPA 1127:
4.13.7 The function of firing circuits and onboard energetics shall be inhibited until the high power rocket is in the launching position.
 
If a launch system could inadvertently set off an igniter, I'd rather it did it when my hands were on the clips as opposed to directly beneath the throat. Untwist & connect is going to stay last for this ten-fingered human.

What you may not realize: Static electricity generated as you insert the igniter, may set off the igniter much easer with the ignition clips attached, especially electric match based igniters. A twisted/shorted igniter is much less susceptible to static electricity, as it is inserted, . On the other hand, wire wound igniters for the most part don't have the same static electricity sensitivity because of there higher resistance.
 
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Hmmf, this newbie is considering an RMS 18/20 for some 18mm Estes Rockets that I am building (and hopefully the Odd'l "Pigasus" shortly). I had D/L'd the Aerotech instructions and saw said plan to insert the igniter during assembly. Now I wouldn't dream of attaching clips to the igniter until I was on the rod (and at that, without the terminal clips on the launch battery attached), but now y'all have me scratching my head... and why would a highly regarded manufacturer like Aerotech say that if it was a danger and/or against fire & rocket club codes? Or maybe I'm reading too much into it.

And thanks, rocketguy101, for putting these together for us!
 
What you may not realize: Static electricity generated as you insert the igniter, may set off the igniter much easer with the ignition clips attached, especially electric match based igniters. A twisted/shorted igniter is much less susceptible to static electricity, as it is inserted, . On the other hand, wire wound igniters for the most part don't have the same static electricity sensitivity because of there higher resistance.
I think we're saying the same thing -- insert, untwist, attach.
 
Hmmf, this newbie is considering an RMS 18/20 for some 18mm Estes Rockets that I am building (and hopefully the Odd'l "Pigasus" shortly). I had D/L'd the Aerotech instructions and saw said plan to insert the igniter during assembly. Now I wouldn't dream of attaching clips to the igniter until I was on the rod (and at that, without the terminal clips on the launch battery attached), but now y'all have me scratching my head... and why would a highly regarded manufacturer like Aerotech say that if it was a danger and/or against fire & rocket club codes? Or maybe I'm reading too much into it.

And thanks, rocketguy101, for putting these together for us!
Because the nozzle throat is so small that the igniters head will not fit through the nozzle, there are very few motors that AT recommends this procedure for and most RSO's/Clubs are aware of it and make allowances for it, however extra care is needed.
 
Hmmf, this newbie is considering an RMS 18/20 for some 18mm Estes Rockets that I am building (and hopefully the Odd'l "Pigasus" shortly). I had D/L'd the Aerotech instructions and saw said plan to insert the igniter during assembly. Now I wouldn't dream of attaching clips to the igniter until I was on the rod (and at that, without the terminal clips on the launch battery attached), but now y'all have me scratching my head... and why would a highly regarded manufacturer like Aerotech say that if it was a danger and/or against fire & rocket club codes? Or maybe I'm reading too much into it.

And thanks, rocketguy101, for putting these together for us!
For very small throats it's not always possible to follow best practice. With these loads and the CTI g65 Moonie I see some people at the pad pull off the aft closure, feed the still-shorted starter in, replace the bottom end, then proceed.

I haven't needed to do this myself with the d21's, but I haven't tried the d2.3's.
 
Thanks, all. As I see the instruction, yes, there is a cap that is apparently blown off by the ignition - the instructions say to vent it wit a 1/16" slice off of one corner. So you just ease that off, insert the igniter, put it back for flight configuration, then into the rocket, onto the pad and proceed with connection, arming, and firing? Sounds like a plan! A safe plan, that is...
 
Thanks, all. As I see the instruction, yes, there is a cap that is apparently blown off by the ignition - the instructions say to vent it wit a 1/16" slice off of one corner. So you just ease that off, insert the igniter, put it back for flight configuration, then into the rocket, onto the pad and proceed with connection, arming, and firing? Sounds like a plan! A safe plan, that is...
Not the cap, the aluminum closure.
 
It is the high power code that prohibits igniters being installed in high power motors until you're at the pad.

Putting the igniter into these small 18mm reloads is similar to putting the starter in an estes motor before you're at the pad.
 
I was assembling some reloads for the first time and they seem to be very tight going in to the motor tube. Any way to fix that?
 
At my TRA level 1 cert, the other flyers backed by a range officer had a long winded serious story of a high powered rocketry L-3 , M-class motor with igniter inserted away from a flight line launch pad knocking out a section of a wall of a motel from inside a room. I do not think that group of people were talking crap. A flyer with his wife were able to tilt the motor away from themselves or other people nearby as it ignited. No igniters were near our HPR models on the bench with motors fully assembled in full view. Beyond the flightline the RSO held my igniter with my rocket on the pad, until it was time to connect the igniter to his electronic launch clamps, and at that point I had permission to insert the igniter into the casing and coil the wire around the clamps. It is something TRA takes seriously and after that story, I don't have a problem with them taking an extra safety measure to reduce risks.

A low power motor wouldn't have the damage involved, but you could still reduce risks of it igniting by keeping igniters away until it is ready to fly. Or another way would be build it with the RSO next to you at the pad if its easy and quick to build, because you are allowed to handle the igniter at that point if you were limited to TRA events.

That was at Danville Dare 89 or 90 and it was an I-65 being tested with an Ignitor tester the user had won at the raffle. I was there and saw the smoke out the window, not the wall knocked down.
 
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