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Richard

Richard

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Eric,

"Materials. I will use only lightweight materials such as paper, wood, rubber, plastic, fiberglass, or when necessary ductile metal, for the construction of my rocket." From the NAR safety code.

This is a fine rocket built with significant skill and attention to detail. However, this rocket is also pushing the limit of what "when necessary" means with respect to the use of "ductile metal" in the construction. Safety is also an important design consideration. The Defender MkII might be able to fly again after taking a core sample out of a soccer field or a child's head but I do not think that to be the optimal engineering compromise between safety and strength.

That said, with honest sincerity, I applaud your efforts to bring fresh ideas to the hobby.

I would be proud to design and construct such a rocket for my own use where I have complete control over the circumstances under which it would be flow so that I could mitigate risks. I don't think I would ever kit a rocket like this where the judgment and skill of the builders will necessarily be an important and uncontrollable variable. It is not just an issue of legal liability, I pray for tort reform, it is a matter of conscience.

Regards,
Richard
 
Richard said:
Eric,

"Materials. I will use only lightweight materials such as paper, wood, rubber, plastic, fiberglass, or when necessary ductile metal, for the construction of my rocket." From the NAR safety code.

This is a fine rocket built with significant skill and attention to detail. However, this rocket is also pushing the limit of what "when necessary" means with respect to the use of "ductile metal" in the construction. Safety is also an important design consideration. The Defender MkII might be able to fly again after taking a core sample out of a soccer field or a child's head but I do not think that to be the optimal engineering compromise between safety and strength.

That said, with honest sincerity, I applaud your efforts to bring fresh ideas to the hobby.

I would be proud to design and construct such a rocket for my own use where I have complete control over the circumstances under which it would be flow so that I could mitigate risks. I don't think I would ever kit a rocket like this where the judgment and skill of the builders will necessarily be an important and uncontrollable variable. It is not just an issue of legal liability, I pray for tort reform, it is a matter of conscience.

Regards,
Richard
Click to expand...

I can fly a dual deploy rocket on G motors all day long at an NAR launch, without any questions. Typically this type of rocket would have steel rods in the electronics bay a few inches down from the nose cone. I'm not seeing much difference from an unsafe perspective compared to an aluminum bulkhead in the nosecone base.

This rocket is ... badd azz:)
 
Richard said:
Eric,

"Materials. I will use only lightweight materials such as paper, wood, rubber, plastic, fiberglass, or when necessary ductile metal, for the construction of my rocket." From the NAR safety code.

This is a fine rocket built with significant skill and attention to detail. However, this rocket is also pushing the limit of what "when necessary" means with respect to the use of "ductile metal" in the construction. Safety is also an important design consideration. The Defender MkII might be able to fly again after taking a core sample out of a soccer field or a child's head but I do not think that to be the optimal engineering compromise between safety and strength.

That said, with honest sincerity, I applaud your efforts to bring fresh ideas to the hobby.

I would be proud to design and construct such a rocket for my own use where I have complete control over the circumstances under which it would be flow so that I could mitigate risks. I don't think I would ever kit a rocket like this where the judgment and skill of the builders will necessarily be an important and uncontrollable variable. It is not just an issue of legal liability, I pray for tort reform, it is a matter of conscience.

Regards,
Richard
Click to expand...

where is excesive use of metal... the only two places i see it is in the nosecone(inside of it for a bulkhead.) and the tail cone...
the rest i think is G10 and pvc...??
this is pretty standard as i have seen in rockets.

This isn't any more metal than otherwise seen in other rockets, (need we talk a bout a manufacturer that puts aluminum tips on thier nose cones...)

I dont see anything that is any more dangerous than any other rocket?
 
Richard said:
Eric,

"Materials. I will use only lightweight materials such as paper, wood, rubber, plastic, fiberglass, or when necessary ductile metal, for the construction of my rocket." From the NAR safety code.

This is a fine rocket built with significant skill and attention to detail. However, this rocket is also pushing the limit of what "when necessary" means with respect to the use of "ductile metal" in the construction. Safety is also an important design consideration. The Defender MkII might be able to fly again after taking a core sample out of a soccer field or a child's head but I do not think that to be the optimal engineering compromise between safety and strength.

That said, with honest sincerity, I applaud your efforts to bring fresh ideas to the hobby.

I would be proud to design and construct such a rocket for my own use where I have complete control over the circumstances under which it would be flow so that I could mitigate risks. I don't think I would ever kit a rocket like this where the judgment and skill of the builders will necessarily be an important and uncontrollable variable. It is not just an issue of legal liability, I pray for tort reform, it is a matter of conscience.

Regards,
Richard
Click to expand...

If it bothers you that much, don't buy one!

I, for one, am impressed with this out of the box consideration for all parts of the traditional mid-power rocket kit. The next kit I buy will be one of Eric's.

G.D.
 
I have two other kits in line waiting to be built but this one is for sure going on that list. Nice job, looks like a fun build and a nice little rocket. I have a CTI 24mm case all ready for one!
 
Richard,
Don't sugar coat an attempted slam with pleasantries like "I applaud your efforts" then in the next sentence talk about a rocket going through a childs head! WTF you seem like one of those people who detest anything other than Estes 1oz cardboard kits, please...the kit is legal innovative and unique....
Ever heard of public missiles? PVC hello?
Ever heard of Aeropack? Aluminum retainers hello?
What about FG? Or carbon? Ever heard of oh I don't know...every rocket manufacturer out there? Get a grip....

Eric your kits are awesome rock on!
 
MarkH said:
I can fly a dual deploy rocket on G motors all day long at an NAR launch, without any questions. Typically this type of rocket would have steel rods in the electronics bay a few inches down from the nose cone. I'm not seeing much difference from an unsafe perspective compared to an aluminum bulkhead in the nosecone base.

This rocket is ... badd azz:)
Click to expand...

Mark,

I happily agree that the Defender MkII is "... badd azz". I even think that the aluminum bulkhead in the nosecone base is rather cool and impressive. How exactly is it necessary?

Some years ago, at a DARS launch, a member flew a large and heavily fiberglassed HP pyramid that failed to deploy recovery. It came in fast and landed point first in the prep area about twenty feet from my children. The racketeer proudly proclaimed "no damage". Admittedly, this is an anecdotal example, but it is also illustrative and the event informed my perspective on the engineering. An amateur rocket should be designed to safely perform for the intended flight profile and the flight profile should omit surviving a crash landing. I would respectfully submit that a rocket that survives such a landing without significant damage is poorly designed from a safety perspective.

Ideally, when one of my rockets crashes, I want it to look like an Indy car impacting a wall at speed and for the same obvious safety considerations. I can build another rocket and, fortuitously, I just happen to enjoy building rockets.

I don't comprehend how an aluminum bulkhead in the nosecone base of a small midpower rocket is a "necessary" use of "ductile metal". I would, however, gladly submit to your tutelage.

Regards,
Richard
 
Highpowerrocketyahoo said:
Richard,
Don't sugar coat an attempted slam with pleasantries like "I applaud your efforts" then in the next sentence talk about a rocket going through a childs head! WTF you seem like one of those people who detest anything other than Estes 1oz cardboard kits, please...the kit is legal innovative and unique....
Ever heard of public missiles? PVC hello?
Ever heard of Aeropack? Aluminum retainers hello?
What about FG? Or carbon? Ever heard of oh I don't know...every rocket manufacturer out there? Get a grip....

Eric your kits are awesome rock on!
Click to expand...
That was a rather caustic response, but I will take it at face value and not assume that I understand your views without bothering to inquire. I will, however, assume that there was no ill intent when you reversed the order of my statements.

I would agree that the "kit is legal innovative and unique". I have heard of public missiles, PVC, and I own and use Aeropack aluminum retainers. I have also used fiberglass, carbon fiber and other materials in, what I hope, are appropriate places for appropriate reasons. A cogent argument can be made for the use of aluminum retaining rings as a substitute for multiple blind nuts, screws and clips. Much of what constitutes "necessary" is going to involve subjective judgments about the merits of available alternatives. As an example, I prefer using rail buttons over rod guides even if the rail buttons involve adding metal screws because I think that largely eliminating rod whip is a good trade off against adding the machine screws to the rocket. Some might disagree with my evaluation.

I understand that the machined aluminum parts of the MkII are "cool", I experience the appeal, but I don't understand how the use of the aluminum centering ring or the aluminum nose cone base are "necessary" or even a good trade off compared to the many conventional alternatives. Please provide a good dispositive argument for the necessity of these parts and I will be pleased to amend my views to conform to yours.

Lots of things are cool but not necessarily safe or wise and many people exercise poor judgment which is likely why the NAR has a safety code.

Regards,
Richard
 
Last edited:
"I understand that the machined aluminum parts of the MkII are "cool", I experience the appeal, but I don't understand how the use of the aluminum centering ring or the aluminum nose cone base are "necessary" or even a good trade off compared to the many conventional alternatives. Please provide a good dispositive argument for the necessity of these parts and I will be pleased to amend my views to conform to yours.

Lots of things are cool but not necessarily safe or wise and many people exercise poor judgment which is likely why the NAR has a safety code.

Regards,
Richard "

Hi Richard,

Thanks for your input. Yes I can offer you a conformal 1010 rail guide at additional cost.
The aluminum bulk plate for the nose cone weighs less than the Chunk of hardwood used in the Mk1. Less weight= less transfer of energy which equals Less more damage to a kids head. BASIC Physics.

Same applies to centering ring. It weighs less than wood, screw and Epoxy.
We just had a gentleman fly a 10lb stubby rocket for L1. He needed a 50" chute. The kit should have been about 2.5lbs max.
Did they stop him? Heck no.
Would NAR approve hell yes!
Dude you can't fix stupidity!!

Really what will do more damage 10 or 20 grams of 6061 or 1lb of epoxy??
Really not that important when you consider the motor tube,Forward bulkhead
Thrust ring, etc are all 6061. I don't think my Centering Ring and nosecone bulkhead are adding to that picture.

My argument is simple if you want to use a Wooden Plug and an eye screw feel free to do so. I'm just not compelled to kit it for the sake of a code being taken out of context.

NAR was dragged Kicking and Screaming into MID/HP rocketry, You and I both know that. I'm a Proud member of Tripoli, I would not accept a free life time membership to NAR. All they really want flown are Paper Rockets. They do great work with the Kiddies though I will give them that! I'm after innovation and you can't honestly tell me My product is unsafe. I also make Propellant, My own Motors, nozzles etc. I know what I am doing.

I refuse to comply because some Lawer/Politico says It's the Law.
When they outlaw smokes I'll roll my own.
When they oulaw Guns I'll make amy own
Freedom is almost gone in the USA!

Seriously, If you fear the welfare of your children at a rocket launch, Why would you bring them?
At the Least have them wear football Helmets.

I'm not trying to be a smartAzz, Really I'm not. I'm trying to reason with you and have you think this through logically.


Peace, Love and Happiness



PS Let me know if you want the rail guide when you order.
 
Last edited:
I do agree that the aluminum CRs, nose block, etc are completely overkill. but hey, it wouldnt be Badazz if it wasnt.
 
Aksrockets said:
I do agree that the aluminum CRs, nose block, etc are completely overkill. but hey, it wouldnt be Badazz if it wasnt.
Click to expand...

On the Centering ring it provideds a much needed anchor point for the screws to lock the boby in place.

I machine metals everyday so the 6061 Nose Bloc was a natural fit.
It is light and stronger than a woody!:D
 
Eric,

If the choice was truly between "10 or 20 grams of 6061 or 1lb of epoxy", a false bifurcation, then even the most obtuse would applaud your selection or 6061. Happily 3/16" or even 1/8" plywood is more than sufficient for centering rings, bulkheads and base plates in mid power rockets with the density of the plywood being about 500 to 700 kg/m3 compared to about 2800 kg/m3 for 6061. Less mass equals less kinetic energy which equals less damage to a kids head. Basic physics.

"My argument is simple if you want to use a Wooden Plug and an eye screw feel free to do so. I'm just not compelled to kit it for the sake of a code being taken out of context."

Your simple argument is not an argument at all for why aluminum is the better choice for the nose cone block or the centering rings, it is simple a granting of permission for people to kit bash your rocket. You then continue on into an irrelevant rant about the NAR, lawyers, politicians, guns and freedom, none of which are germane to the consideration of what materials are best, from an engineering standpoint, to be used in a mid power rocket. Also, as I quoted the entire section of the NAR safety code concerning "Materials", I will gladly submit to the judgment of the forum as to weather or not I have taken the code out of context.

From one of your subsequent post; "... I machine metals everyday so the 6061 Nose Bloc was a natural fit. ...". I think this is likely the core of the issue. I think it likely that you don't really have an engineering reason why 6061 was a "necessary" use of ductile metal, it is simply your preference because you are comfortable machining parts out of 6061.

I do not want to jump to conclusions but I am beginning to understand that you don't really take the safety code seriously and that you have some level of emotional hostility towards the NAR as an organization. What I had earnestly hopped is that you actually had a good and sound engineering reason for your use of aluminum in places such as the nose block for then I would have learned something of utility from you but I can certainly live with this minor disappointment.

"... and you can't honestly tell me My product is unsafe." To be fair, this is a true statement. What is safe or unsafe necessarily involves a subjective evaluation of risks and how well those risks are mitigated by the design of a product. Safety is a continuum and not quantized into two easily distinguishable states of safe and unsafe. What I can say is that your product could easily be safer but even this is also true of many products and all products can be incrementally safer but at what cost? What is also true is that many people, perhaps even most, lack the requisite skills to adequately make these subjective evaluation about safety. "Dude you can't fix stupidity!!" This is why we have all witnessed "... a gentleman fly a 10lb stubby rocket for L1." and why, I would argue, that a safety code, such as the one promulgated by the NAR, is a good idea even if it is poorly implemented by range safety officers. Many people purchase kit rockets with the expectation that the designers of kits have the requisite skills to make sound judgments concerning safety even if the customer does not.

Furthermore, unless we fly privately, the judgments we make concerning the safety of our rockets are also imposed on the other participants and spectators at rocket events. As a matter of conscience, the risks I am willing to take for myself are certainly different than the risks I am willing to impose on others.

Overall, I like your designs and I admire your drive to innovate and I think that your kits are priced to be a good value especially considering the quality and workmanship of the parts.

I thank you for taking the time to consider my criticisms and I hope that you will engage in a little honest introspection.

Regards,
Richard
 
Last edited:
One idea overlooked.
What if! cause thats the game played here.
your rocket, with ductile metal was at a sanctioned launch, and the said rocket was involved with 'any' insurance claim.

when at that time, the insurance company says, please explain why this metalic ring/bulkhead, is not a less dense/ductile material.
common ballistcs tell you why you want an impact to fragment, in lieu of being ductile and holdign mass through penetration; in this case.
The insurance denies the claim, and pulls coverage and walks away because you cant prove your rocket 'required' that metalic component.

That has nothing to do with NAR or TRA...
Both have that same code, Eric you should know that. As a fellow TRA member(who doesnt partake in NAR, for the same EX reasons...) think its small to compare the two in difference, when they organizationally collude and help eacher with our commonality. Im TRA, and i fly paper rockets....

Eric has a chance to be selling rockets, that particular clubs may not RSO if they believe the aluminum is 'extruding' this use.

(this comming from a guy with an ALL aluminum avionics bay.)

I think Richard has taken an unpopular position, but i agree with him, and Eric at the same time.
Eric can deffinatlely produce anything that falls outside the code, even if he wants to.. Weather, its a percieved difference, or even an outlandish direct decision to do the contrary.

As flyers, and RSO's we look at it differently when its our insurance, and range safety. (which is why i have a rocket with an aluminum tip, that never flies with the tip... and never will.....since the biggest motor i can cram in only just breaks mach, i would never be able to prove-its structuraly required.)
 
Eric1 said:
Really what will do more damage 10 or 20 grams of 6061 or 1lb of epoxy??
Click to expand...

Really, i would rather get hit by a gallon of epoxy, than 3/16" allthread....

thats like saying... do you want blunt trauma or shot to death....
 
Eric1 said:
NAR was dragged Kicking and Screaming into MID/HP rocketry, You and I both know that. I'm a Proud member of Tripoli, I would not accept a free life time membership to NAR. All they really want flown are Paper Rockets. They do great work with the Kiddies though I will give them that!
Click to expand...

"A high power rocket vehicle intended to be propelled by one or more high power solid propellant rocket motor(s) shall be constructed using lightweight materials such as paper, wood, plastic, fiberglass, or, when necessary, ductile metal so that the rocket conforms to the other requirements of this code."

That's from Tripolis' HPR safety code. Pretty much mirrors the NAR code.

Eric1 said:
I refuse to comply because some Lawer/Politico says It's the Law.
When they outlaw smokes I'll roll my own.
When they oulaw Guns I'll make amy own
Freedom is almost gone in the USA!
Click to expand...

What this tells me is that you really don't care whether the ductile metal is necessary or if your rockets are or are not any less safe than those made with more traditional materials. That's fine, and I respect your political views/beliefs on such things, but that really doesn't answer the question at all. Honestly, I'm inclined to think that the cone block is little different from a safety concern than washers attached to a cone to add nose weight. But I'm no expert and you chose to rant instead of answering the question so I really don't know. In fact, that part of your reply implies that your rockets might be outside the safety codes but you just don't really give a damn. As a potential customer who mostly launches rockets with my "Kiddies", I do give a damn and am curious as to what testing or calculations you've made, if any, in regard to how your innovative and nontraditional materials might affect safety.

Eric1 said:
I'm not trying to be a smartAzz, Really I'm not...

PS Let me know if you want the rail guide when you order.
Click to expand...

Maybe it's just the difficulty of reading intent without the benefit of hearing tone of voice or seeing body language and facial expressions, but that does seem a bit smartAzz. As a potential customer, the most important things to me when making rocket purchases are kit appeal and quality (and yes, safety is part of quality), value, and customer service. And while your rockets are appealing and seem to be an excellent value, I still haven't decided about the safety aspect of the quality. You seem to be refusing to give a respectful answer of any kind. And that lack of respect raises concerns about the kind of costumer service one might receive from your company.



I debated a lot about whether to even get in the middle of this. I really don't know if the metal used in your rocket kits are necessary, or whether there are increased safety issues with the materials. I'm not trying to take sides at all. What it boils down to is that I do like the designs, think their target price is appealing, and would seriously consider purchasing one or more of them. But when I first saw your designs, I had the same questions about the use of metal as Richard does, and looked forward to seeing your responses to alleviate my concerns. But instead of seeing a thought out polite response providing sound reasoning and counter points to Richard's questions, I have been seeing responses one would see on a Jr. High playground.

Seriously, I fly rockets with my kids and most people that launch mid-power rockets such as yours do so at club launches where there are numerous other people, including kiddies, and as such safety has to be considered. In fact, the range safety officer will be considering it. And if I'm going to buy one of your kits, I would like to know that you as the designer put some thought into how the innovative materials might affect safety, if for no other reason than to have a legitimate response if the RSO asks the same questions. If you didn't, that's fine. If you don't care and think your kits should only be flown at Tripoli launches where no kids are allowed (are there such launches?), that's fine too. Just explain that and I'll say thank you and will follow with interest any build threads of your kits and hope folks post videos of launches. But I won't be purchasing any.

If you did give consideration to the safety questions, that's great. Could you then please go through your thought process, any testing or calculations you performed, that took you to the conclusion that there aren't any significant increases in risk with your design. In fact, such a response posted a page or two back would have kept this thread focused on the Defender MkII, which I'm sure would be much better for your business.
 
MrGneissGuy said:
"A high power rocket vehicle intended to be propelled by one or more high power solid propellant rocket motor(s) shall be constructed using lightweight materials such as paper, wood, plastic, fiberglass, or, when necessary, ductile metal so that the rocket conforms to the other requirements of this code."

That's from Tripolis' HPR safety code. Pretty much mirrors the NAR code.
Click to expand...

Both safety codes, are mirrors or direct adoption of NFPA... my favorite association!!:)
 
The idea that making rockets out of light weight materials makes them safe is a fallacy. Any rocket that comes in ballistic is dangerous, we have all seen even estes rockets come in with out a chute, and bury themselves in the ground. Honestly, what do you think they would do to a person? By the time you get to mid power, where rockets weigh over 1 pound, they have more than enough kinetic energy to kill someone, bear in mind that a bullet weighs much less. The laws of physics do not care what a rocket is made of, only how fast it is traveling, or how much it weighs. What makes this a safe hobby, is that most of the people are aware of the dangers. If you believe flying rockets is not dangerous, then you have no business flying rockets, regardless of what they are made of.

Jeremy
 
MrGneissGuy said:
Could you then please go through your thought process, any testing or calculations you performed, that took you to the conclusion that there aren't any significant increases in risk with your design.
Click to expand...
It depends on what you are comparing it to. If you really want an indestructible rocket, get a Blackhawk 24 or 29. I didn't see the safety bitching about them when they were introduced. Yes, I do think the BadAzz kits are way overkill, but so are the Blackhawks. Both just disappear on F motors.
 
FYI.....

earlier this spring at Thunderstruck, I was talking to a fellow rocketeer. We were both leaning on his trailer. You know the U-haul type with aluminum panel sides.

We weren't 3 ft apart when suddenly ........wham....kerblang! IT flew right between us, punched a clean round hole right through the aluminum panel, went partially into the plywood inner liner he had installed, bounced back and landed 10 ft away!

IT was a little ole Alpha with the orange plastic NC & fincan. IT suffered no damage what so ever and flew again later! IT flew on a C motor. Had it hit one of us we certainly would have been hurt. [unless of course it hit me in my HARD head, then the rocket would have been destroyed LOL]

Anyway for some strange reason that flight went unstable, a proven design, a proven kit, probably sold millions of them by now.

It just goes to show when at a launch, it's up to each of us to be aware of the dangers involved with rockets. We have all been lulled into complacency, BUT be it wood, plastic, metal or fiberglass, if it's moving fast enough regardless of size,materials, design..... no rules, regulations or codes will protect us better than plain old common sense!

Rocket Launch... Danger..... enter at your own risk.

Semper Fly,
CJ
 
Ahh, Forums, You gota love em.
Someone earlier said there one in every crowd ( roughly ), I find they travel in packs.


WOW Eric, those were some BIG letters, scared me!:bat:
hahaha
 
dlb said:
Ahh, Forums, You gota love em.
Someone earlier said there one in every crowd ( roughly ), I find they travel in packs.


WOW Eric, those were some BIG letters, scared me!:bat:
hahaha
Click to expand...

Just want the Yahoo to be sure to see the post!:dark:
Seriously, I'd hate think of someone smack talking me at a launch like that.
Thier day would take a turn south Real Quick.

You are right about traveling in packs, most feminine hygene products Do!!!
 
Last edited:
I would have never guessed that this thread would turn this ugly.:(
:pop::pop::pop::pop::pop::pop:
 
Aksrockets said:
I would have never guessed that this thread would turn this ugly.:(
:pop::pop::pop::pop::pop::pop:
Click to expand...

My apologies, I don't like it either. Thier argument is moot. If you don't like a componet in a kit, replace it. Simple.

Any way, I LOVE the H123 Skid Photo on your site!! It's one of the best I've ever seen!

Peace, Love and Happiness
 
Eric1 said:
My apologies, I don't like it either. Thier argument is moot. If you don't like a componet in a kit, replace it. Simple.

Any way, I LOVE the H123 Skid Photo on your site!! It's one of the best I've ever seen!

Peace, Love and Happiness
Click to expand...

:roll: I dont have access to my photos at home so that one is not mine. I dont actually think that it is an H123 either (more like an M). I just looked up "skidmark rocket motor" on google and found the best one. Most people that visit my blog are grandparent / friends so i dont think that they would care about the spefics of the motor. The photo is just an example of a skidmark. I cant find the original owner so i dont know who to credit it to.
Sorry
 

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