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Should you kit an L3 cert?

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DavidMcCann

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Splitting off wild man's thread, this discussion came up. To be blunt- It's not required to scratch build, and anyone who says it should be is an elitist jerk.



I agree with this and would like to see Level-3 have to be a scratch built rocket and not a kit. I might get slammed for this but your building and design skills are really only demonstrated with a successfully flown and recovered scratch build rocket. I've seen scratch built Level-2 rockets that were more demanding than some Level-3 rockets made from a kit.
It takes some good design and building work to make a rocket fly successfully on a G-M motor. If someone bought a Drago EX for their L-3 would anyone have a problem with that?

No. There is nothing wrong with building a kit for your L3. I'm in the process of building a Widman Extreme for mine. Don't like it? Kiss it. With those motors, and the challenges of recovery etc, there is little difference between buying a kit, and grabbing parts. You're talking about cutting fins and slotting the tube. Oh that's so special.
 
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noffie79

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I think I'm just gonna sit back and watch the show. Should be a good one! Lol
 

CzTeacherMan

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I built a custom made kit. Does that count?
Gizmo XL-DD-V (extra two fins).
And...AND... It's a squat rocket so it required a bit of calculating for nose weight. So there. Yeah.
 

DavidMcCann

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I think I'm just gonna sit back and watch the show. Should be a good one! Lol
That's the Idea.

But in a less inflammatory way- A kit is a collection of parts, and I've never really seen two kits built the same. You're really just talking about cutting them out yourself or not.... unless you're talking about rolling your own tubes, which just....no.
 

dhbarr

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If you're not personally weaving your own single walled carbon nanotube unidirectional fabric, you should just go back to RTFs & LPBs. /s
 

noffie79

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That's the Idea.

But in a less inflammatory way- A kit is a collection of parts, and I've never really seen two kits built the same. You're really just talking about cutting them out yourself or not.... unless you're talking about rolling your own tubes, which just....no.
I agree. Everyone has different building techniques. I don't see the difference in building a "kit" or buying a collection of parts and building those.
 

michigander

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Kit is fine :) I 100% love the idea of using 4" tube , I'm using 4 1/2 diameter 11K + mach 1 + flight



My LLC3 even drove 180 miles each way last winter to check out the workshop here :)
 

jd2cylman

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I used a Kit. I had to source a coupler of the correct diameter and length because the material the body tubes are made of are no longer made. Then with some expert help, we sanded the custom made (by a third party) coupler to fit my tubes. I still had to fit the centering rings to the motor tube and body tube. I had to sand the fins to make them all the same length (one was off an 1/8". My low level OCD couldn't leave that be...). There wasn't ANY recovery materials in the kit. All that I had to figure out on my own. I had to decide what sort of AV bay end caps to use and how many tie rods to hold it all together. As was already stated, the only thing the kit save me was slotting the tube and cutting out the fins. Sure my rocket is just a 3FNC. But that's how I like them (well, most of the time I like four fins...). Once I thought five fins would be better, but I talked some fool into building that one for me for him to use as HIS L3 (success!). Oops didn't see that Erik already posted... :wink:

Adrian
 
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CzTeacherMan

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I used a Kit. I had to source a coupler of the correct diameter and length because the material the body tubes are made of are no longer made. Then with some expert help, we sanded the custom made (by a third party) coupler to fit my tubes. I still had to fit the centering rings to the motor tube and body tube. I had to sand the fins to make them all the same length (one was off an 1/8". My low level OCD couldn't leave that be...). There wasn't ANY recovery materials in the kit. All that I had to figure out on my own. I had to decide what sort of AV bay end caps to use and how many tie rods to hold it all together. As was already stated, the only thing the kit save me was slotting the tube and cutting out the fins. Sure my rocket is just a 3FNC. But that's how I like them (well, most of the time I like four fins...). Once I thought five fins would be better, but I talked some fool into building that one for me for him to use as HIS L3 (success!). Oops didn't see that Erik already posted... :wink:

Adrian
Indubitably. No simple task working around five fins for everything....... But damn it looks good!
 

MClark

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Can't respond, I am mining sand to draw into fiberglass.

The TRA TAP committee and BoD hashed over this years ago.
Kits are OK.

M
 

Cl(VII)

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I scratch built my L1 and L2, and I am scratch building my L3. That is how I chose to go, but I don't think it should be required. In fact, I kinda wish I would have went with a kit for the L3. Certainly would have been much faster.

Scratch building itself also has a great span...some folks may not even consider my builds true scratch building.
 

KilroySmith

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The current rules are what they are. Flyers should be held to the rules, but not more. I built a kit rocket (Madcow Torrent) for my L1, and used a DMS I280DM for my first HPR flight. I stuffed a DMS J270 into it for my second HPR flight and L2 attempt, and was successful. Within the rules, I could build an L3-capable kit as my second HPR rocket, and certify L3 on my third HPR flight. Those are the rules. I understand the original sentiment - a L3 is the highest certification the sport provides. You're assumed competent enough to buy any motor that's available, and to build and fly any weight rocket you wish, and that you've developed both the knowledge and the wisdom necessary to do that. Would that apply to me if I went down the path I described - never having designed a rocket, built a motor, or appeared at more than two rocketry events? Unfortunately, I don't know how you create a build requirement that demonstrates "knowledge and wisdom". No Kits? OK, then L3 candidates will modify a kit - extra fins, an Avbay, shorten a tube, whatever's necessary to surpass the "no kit" requirement. Perhaps you decide "No Kits, and nothing based on a kit" - well then L3 candidates will simply google 3FNC plans for OpenRocket and order the parts. "Gotta come up with your own design" is great - but impossible to police. Some organizations try to solve this problem by specifying a number of hours of experience, or number of flights, or simply calendar time that must occur between certification levels. NAR has chosen not do that; it means that the minimum work required to get the highest certification is pretty danged small. The real question is, has this been a problem? To me, it seems like an L3 should demonstrate a certain level of experience and expertise. It'd be great if the L3 requirements were something like: 1. The L3 exam includes a candidate L3 rocket design that the L3 candidate would have to critically review - "Would you let this rocket fly". 2. The L3 candidate would have to log some number of HPR flights since L2. 3. The L3 candidate would have to log flights from 3 of 5 different categories - a minimum diameter mach+ flight, a heavy rocket, an HPR cluster, a 2-stage HPR rocket, a declared altitude rocket, a glider, a competition rocket, etc. Note that not all of these need to be HPR rockets. 4. The L3 candidate has to demonstrate knowledgeable building practices. /frank
 

sharkbait

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Splitting off wild man's thread, this discussion came up. To be blunt- It's not required to scratch build, and anyone who says it should be is an elitist jerk.






No. There is nothing wrong with building a kit for your L3. I'm in the process of building a Widman Extreme for mine. Don't like it? Kiss it. With those motors, and the challenges of recovery etc, there is little difference between buying a kit, and grabbing parts. You're talking about cutting fins and slotting the tube. Oh that's so special.
I don't believe it matters if your L3 is a kit or not. Like you said the forces imposed by L3 motors and the challenges of recovering an L3 bird will show clearly during your certification flight if you know how to assemble a rocket according to those demands or not.

But I don't agree that a kit and a scratch are both just a pile of parts, generically speaking yes, but there's definitely more auxiliary skills and planning involved with a scratch build. There are varying levels of what we label as "scratch" also. Some are basically just custom kits where the builder orders pre-slotted tubes, pre-cut & beveled fins, pre-cut airframes, a NC, CR's, and a coupler. Then on the opposite end of the scale the builder is rolling his own tubes, laminating his own fins, fabricating his own NC, ect ect. Plus a bunch of combined variations between the two extremes.
 

mpitfield

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I try to get different things out of each cert and up the challenge with each level. That being said I am in the process of designing a scratch L3, but this is a personal choice and I wouldn't think twice about anyone doing a kit, kit bash, scratch or anything in between for their L3...love the diversity.

Now my definition of a scratch in this case is my own unique design, but the tubes I purchased along with the nosecone, fin plate, etc. I recognize that to some a scratch is a roll your own, which I am leading up to but not likely for this kit, that is unless the tubes I acquired turn out to be inappropriate, which is unlikely. However in such a case I would still use the nosecone and plates.
 

DavidMcCann

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Another factor brought up was going 1-2-3 on one rocket. It's basically a no-go in NAR as I understand it, but can be done in TRA. This freaks out tons of people for some reason, but If a TAP passes it, that throws out most of the arguments against it. Now it's not my style, but if someone wants to... and they are capable, why not?
 

DavidMcCann

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Is it really again NAR rules to use same rocket? I would have no problem with it.

Not being NAR I obvious don't know, but every time it's brought up people claim that you must be L2 before starting L3, and have to submit paperwork before starting construction.

Much much of that is true I don't know, and I've never pursued it further as it doesn't apply to me, but seems to be an accepted requirement in the people I've read here.
 

les

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Most (agreed, not all) of L3 rockets are 3FNC, especially those used for a cert flight - generally with the thought of keeping things simple.

This may be a bit controversial, but in the long run, most 3FNC are the same....
yet different

They may be longer/shorter and have different diameters
The nose may be longer/shorter/conical/rounded.
There may be 3/4/5 fins with different chord/spans/sweeps
But in the basic grouping they are the same - kinda like why we classify them as 3FNC vs scifi/fantasy/oddroc/boost glider/etc.

And whether you get the parts as a kit or buy the parts separate I don't feel makes a difference...
But - my opinion + $1.00 is only good to get a coffee on sale from McDonald's.....
 

dixontj93060

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I feel less concerned about scratch, kit or modified kit versus a L3 candidate being able to do basic analysis of the flight and the math/physics impacting each segment of the flight plan. I have argued for some standards in these areas with no success so I will shut up now.
 

Aksrockets

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The amount of complexity between "L3 size" rockets varies wildly. There is almost no comparison between A: going out, slapping together a LOC Bruiser, then flying it on an M1297 and B: constructing an experimental 2 stage EX O-N and flying it to 115,000 feet. The two might as well be entirely different hobbies. Although the basic physics are still essentially the same, the mindset, the construction materials and problem solving between the two couldn't be more different. Although both fliers might have the same certification, their experiences are very different. A certification is a demonstration of skill in building an "L3 sized" rocket, and I believe it's demonstration not only for the mentors and peers, but for the flier. If your goal in attaining a L3 certification is to fly that O-N 2 stage, what are you doing proving you can fly a LOC Bruiser? The two are hardly comparable. Fly something where you actually challenge yourself and that you actually want to build. Toss out the Loc Bruiser and build a MD M2245.
Same thing with kit building vs scratch building. If you know all you're going to do is build wildman kits all day, by all means get an L3 on a wildman kit! If you're really into those builds where you lay up your own nosecone made with fiberglass from the sand you and Mark mined, then by all means stick to your style for your cert.

I personally don't have my L3, but in about a month I'm going to try a 3in N3500 to 48k and M3.5 (it's technically a group project). Do you guys think flying a 3FNC kit on a baby M to 4k is somehow an accurate assessment of my ability to do so? I've had quite a few people tell me it is.
Sorry for the slightly off topic post, but this issue has been on my mind. Im not implying the need for any more regulation, just sharing my mentality on L3s in general.

Alex
 

cbrarick

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Do what you want to do, as long as it fits in the rules. I used a kit, but they're just a collection of parts that conveniently fit together. Besides, I have no interest in slotting tube - especially fiberglass.
 

DavidMcCann

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The amount of complexity between "L3 size" rockets varies wildly. There is almost no comparison between A: going out, slapping together a LOC Bruiser, then flying it on an M1297 and B: constructing an experimental 2 stage EX O-N and flying it to 115,000 feet.

I personally don't have my L3, but in about a month I'm going to try a 3in N3500 to 48k and M3.5 (it's technically a group project). Do you guys think flying a 3FNC kit on a baby M to 4k is somehow an accurate assessment of my ability to do so? I've had quite a few people tell me it is.
Sorry for the slightly off topic post, but this issue has been on my mind. Im not implying the need for any more regulation, just sharing my mentality on L3s in general.
Here's a shift- whats harder, a Bruiser on an M1297, or a 38mm MD J1000LW?

The important thing to remember is getting an L3 card with an M1297 doesn't let you just walk an O-N out onto the pad. It's still going to get reviewed. The 1/2/3 cert process just acts as a speed bump to keep for lack of a better word - dumbasses walking out with piles of bad rockets. It's not perfect, but it cuts down on volume of stupid.
 

K'Tesh

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Can't respond, I am mining sand to draw into fiberglass.

The TRA TAP committee and BoD hashed over this years ago.
Kits are OK.

M
Wimp... I've already planted the trees that I'm going to cut down (with a herring) for the CR's and fins, and have already begun crushing the bolders into gravel so I can get the sand I need. I'm not looking forward to boiling the horse hooves for the glues (but I'm in China, so a man has to do what a man has to do). :wink:
 
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thequick

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How to make an apple pie (L3 Cert?) from scratch - the Carl Sagan way.

The pace of TV has changed. Wait for it! (Awesome way to start a show... This was real TV back then.)

[video=youtube;6PHO2DZN30k]https://www.youtube.com/watch?v=6PHO2DZN30k[/video]
 
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thomas

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There is no reason a L3 rocket should be scratch build, since it has no safety implications.
You should have all the freedom you want as long as the rocket is safe.

There are much greater problems in the certification process than using a kit for L3.
For example it is pretty much nonsense that you can certify L1 and L2 without a backup recovery system.
Or that you can try as many times as you want, even on the same day with the same rocket.
 

kzimmerman

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You should have all the freedom you want as long as the rocket is safe.
Here, Here! I think scratch building should be encouraged, but the flier should ultimately have the freedom to choose one way or the other. The important part is building a solid rocket, a good recovery system, and evaluation of stability and motor size. Scratch vs kit is irrelevant to those goals, but I feel a certification flight is more to demonstrate a working knowledge of those components rather than a knowledge of advanced building techniques. I scratch build a lot. I have a rocket that I may use for an L3 attempt one day, built totally from salvaged parts. I bought some hardware, the recovery harness and parachute (I don't like the chute, surplus, not very good for rockets) and some fiberglass cloth. Tubes, epoxy all the wood, foam for the nosecone etc. were all salvaged from construction companies and sites. I would not want to see some of the rocketeers I've seen do this, I don't think their skills are up to snuff. I think they should be able to fly kits if they want, and I think I ought to be able to scratch. I think scratching ought to be encouraged because I'm particularly fond of that, and I wish to see more non 3fnc! But, personal choice.
 

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I used a kit, but the build was modified greatly.

I personally think it is up to the builder.
 

neond7

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Can't respond, I am mining sand to draw into fiberglass.
That's the spirit! I planted my own trees from seed to acquire the wood I used to make my own fins. Even forged my own stainless u-bolts from the steel I acquired from meteorites I dug up in the Nambian desert......
 
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