38/640 questions

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rockets said:
I have a couple of questions about a 38/640 hardware set.
Can you put AT or CTI motors in it?
Where can you find KBA & Gorllia rocket motors?
I'm trying to figure out where to get motors for that case at a launch in the midwest.





Thanks,
Click to expand...

Andrew,

KBA reloads are available from Lee Berry at Merlin Missiles. He supports our launches, and delivers too. I may have a reload or two i would be willing to part with to a TRA/NAR L2 certified flyer. BTW, no spacers unless you want to fly Research and that is a whole different conversation, not for this forum.
 
Dudes.. Stop chewing up this kid.... He sounds SO much like what I was when I was his age.
When I was about 14 or 15 I bought a HyperLoc 835 rocket kit. The intention was, I could adapt it down to a 38 and maybe even a 29. I flew it with the help of my parents who at the time had their L2 certs. It went off on a I211 for it's first flight. Now, this was my first ever HPR flight, and I had only flown LPR & some MPR rockets.. I flew it some more times on nice little H, I & J motors anyday!
But, one day, I bought a 54/2560 hardware set for $120. I planned to fly it in my HyperLoc 835. It had just been fiberglassed, and I really wanted to use that 54/2560 hardware!
Well, at my club, I started asking around, to see if anyone had reloads for it.. 4 out of 5 people criticized the heck out of me, and said that even under the help of my parents, I shouldn't even dream of flying that 54/2560 hardware!
And do you know what happened next, I right then and there sold my case, sold my rockets, and left the hobby.
And it was all because a bunch of people criticized me, and it made me want to leave the hobby. And I'm afraid that by the comments of some of you, you might make "rockets" want to leave the hobby.


Just some thoughts.......






Ben
 
RocketryBen said:
Dudes.. Stop chewing up this kid.... He sounds SO much like what I was when I was his age.
When I was about 14 or 15 I bought a HyperLoc 835 rocket kit. The intention was, I could adapt it down to a 38 and maybe even a 29. I flew it with the help of my parents who at the time had their L2 certs. It went off on a I211 for it's first flight. Now, this was my first ever HPR flight, and I had only flown LPR & some MPR rockets.. I flew it some more times on nice little H, I & J motors anyday!
But, one day, I bought a 54/2560 hardware set for $120. I planned to fly it in my HyperLoc 835. It had just been fiberglassed, and I really wanted to use that 54/2560 hardware!
Well, at my club, I started asking around, to see if anyone had reloads for it.. 4 out of 5 people criticized the heck out of me, and said that even under the help of my parents, I shouldn't even dream of flying that 54/2560 hardware!
And do you know what happened next, I right then and there sold my case, sold my rockets, and left the hobby.
And it was all because a bunch of people criticized me, and it made me want to leave the hobby. And I'm afraid that by the comments of some of you, you might make "rockets" want to leave the hobby.


Just some thoughts.......






Ben
Click to expand...
AND, I forgot to mention, this young man started this thread because he had some questions. Not to get chewed up by a bunch of people.





Ben
 
rockets said:
Does anyone know if there's spacers for this case?
I could always start small with the case.. If so, I could fly G & small H motors first, and work my way up from there.
The rocket designed for this 38/640 case was mostly built by my brother, who has his L2. Whatever he didn't build, I did it, and he watched me, and helped me! What a helpful brother!! :)
Yesterday I flew 2 sweet G motors, a G75M, and a G106SK. The G106SK spanked my Partizon to nearly mach one, and it held together, so I know I can build rockets well.





Thanks,
Click to expand...

What one is it? You also posted...

"Need to fix up my Estes Partizon, lots of problems.. The retainer is melted, rail buttons are somewhat melted, the paint is burning off, and since it came in ballistic yesterday, I need to replace the shock cord mount as well........I hope it doesn't need to be retired! And, it went nearly supersonic and almost shredded on my CTI G106SK! "

It doesn't sound like it held together well if your thinking about its retirement. Maybe practice a little more with MPR before thinking about L2 flights. There are a lot of DMS L1 motors available, so you can practice procedures and not worry about hardware loss.

Why did your Partizon come in ballistic?
 
Last edited:
RocketryBen said:
AND, I forgot to mention, this young man started this thread because he had some questions. Not to get chewed up by a bunch of people.





Ben
Click to expand...

and telling him that rushing into L2 motors without experience is a bad idea is completely valid advice. His questions indicate a lack of experience. Saying he should go get that experience isn’t a bad thing.

His inital questions were were answered very quickly.
 
I don't care how many rockets this younger guy destroys. That's part of the learning process. I've destroyed three this year to varying levels of destruction as an adult learning the hobby. This isn't an easy hobby to acquire. We don't need another case of RocketryBen were a younger interested talented individual is denied the opportunity to learn by a bunch of spiteful old geezers. Not all people on this planet are able to shrug off bullies well. You know aviation smiled at fourteen year old kids. People in aviation had the respect to treat others with dignity and recognize the next generation of flyers to help expand the community, because its numbers were so small. Why can't rocketry have that same feeling to it? If you are concerned about a fourteen year old flying high power then don't be mean, embrace the opportunity to mentor him and make sure he flies safely. Sadly a lot of people on this planet are rather blunt and rude about things and as an individual with a dream you must learn to shrug off the naysayers comments and try to achieve that dream anyways.

There were fourteen year olds pursuing a mechanical engineering degree at UTC. Guess what? People were freaking mean to that kid. DARPA recently hired him. DARPA... Kid had enough spunk to keep going towards his dream and ignore snarky judgements. Don't give up no matter how mean people are.
 
Eric said:
Why did your Partizon come in ballistic?
Click to expand...

Seen L-3 rockets come in ballistic at Hellfire 22. It's a helluva lot more scarier when an L-3 does it then bores several feet into hardened ground. Those flyers had a lot of L-1/L-2 practice and that still happened.
 
Andrew_ASC said:
Seen L-3 rockets come in ballistic at Hellfire 22. It's a helluva lot more scarier when an L-3 does it then bores several feet into hardened ground. Those flyers had a lot of L-1/L-2 practice and that still happened.
Click to expand...
Was that suppose to answer my question?

I ask to see if the reason was discovered. Was something learned? Is there knowledge that can be past on?

I didn't ask if anyone has seen scarier ballistic rockets come in.

ANY rocket that comes in ballistic near a crowd of people can be scary...

Sent from my VS988 using Tapatalk
 
His age isn’t the issue, nor cause for the advice to slow down. If he had the experience I’d say push hard. He doesn’t yet and shouldn’t be rushing so fast. That’s not mean, that’s honest advice I’d expect from any of you if I was in the same boat
 
The OP shows no indications of flying an L-2 rocket tomorrow. He indicated he could start with G and H motors in a later post and work his way up. The only way for him to get experience is to have actual flights, with HPR motors. And if he doesn't progress rapidly and learns mastery of electronic deploy on L-1 motors I see no issues of him flying L-2 motors eventually. While the OP is flying L-1 motors he can practice the L-2 written exam.
 
Eric said:
Was that suppose to answer my question?

I ask to see if the reason was discovered. Was something learned? Is there knowledge that can be past on?

Sent from my VS988 using Tapatalk
Click to expand...

Yes David, the reason was discovered and something was learned. The nosecone went thru the chute upon deployment. While I did not help him pack the chute, one of our experienced flyers did and as we all know: "chute happens" and sometimes not in the way intended.

I know that Andrew has ‘irritated’ a lot of posters here by his comments; he has done the same with me on occasion. However, I wish that Tripoli Mid-Ohio #31 had a whole bus load of Andrews. Why? His unbridled enthusiasm, curiosity, and desire to push the envelope are things that I am not seeing in young flyers attending our club launches; I am not sure why. In Andrew, I see a young man that will (hopefully) be entering college as a Level 2 flyer working on his Level 3. We will continue to coach him and answer his questions. At our launch on Saturday, we had six of us helping him and answering his questions.

There is a good possibility that I will get flamed for this, so go ahead, PM me, email me, or even call me: it’s okay. :)
 
Your claim to not care how many rockets he destroys goes against your “OMG there are LIVES on the line here” attitude in other posts. This has no bearing on the topic at hand, but is curious.
 
Nothing replaces actual flight experience. You can't open rocket that experience. You have to fly it.
 
pondman said:
Yes David, the reason was discovered and something was learned. The nosecone went thru the chute upon deployment. While I did not help him pack the chute, one of our experienced flyers did and as we all know: "chute happens" and sometimes not in the way intended.

I know that Andrew has ‘irritated’ a lot of posters here by his comments; he has done the same with me on occasion. However, I wish that Tripoli Mid-Ohio #31 had a whole bus load of Andrews. Why? His unbridled enthusiasm, curiosity, and desire to push the envelope are things that I am not seeing in young flyers attending our club launches; I am not sure why. In Andrew, I see a young man that will (hopefully) be entering college as a Level 2 flyer working on his Level 3. We will continue to coach him and answer his questions. At our launch on Saturday, we had six of us helping him and answering his questions.

There is a good possibility that I will get flamed for this, so go ahead, PM me, email me, or even call me: it’s okay. :)
Click to expand...

No flames; I just want to say thank you for this.
 
DavidMcCann said:
Your claim to not care how many rockets he destroys goes against your “OMG there are LIVES on the line here” attitude in other posts. This has no bearing on the topic at hand, but is curious.
Click to expand...

My first HPR was a scratch built and scratch design prototype multistage. With zero experience so a hypercritical view of materials selection was chosen on a conservative reason. It was also supersonic with many unknowns. I personally treated it more as an experimental flight test program would. We only had one chance to launch it. It was a team effort. We did everything we could to ensure the program went safely but under hard deadlines we did not have time to gain experience in increments. We had enough experience from that first madien test flight to successfully launch a second rocket with design improvements and place third nationally at SEDS USRC college HPR competition. Nor did we have the budget to do so. The first rocket was a complete write off. The lessons learned were invaluable dAta wise as we were testing systems no one had invented in HPR yet.
 
If we didn't destroy a nosecone with thin shoulder radius. We wouldn't have known its failure point. There simply wasn't a Mach 1.7 wind tunnel for a custom nosecone to shatter it on ground experimentally. If you don't break it you can't improve it. We had a Mach 1 wind tunnel for a 1" x 1" cube de-rated to Mach 0.8. No amount of Mach 0.8 testing would have solved the problem. No one else had off the shelf supersonic airfoils in geometry we desired. Of course the risks were higher than a normal certification flight. We had an L-3 flyer actually fly our competition rocket at one launch. Not trying to give anyone bad advice. Perhaps we were a tad aggressive on the testing.
 
Rockets, If you have the Silver 640 motor...it's an AMW. If it's gold, Kosden.

AMW case you can fly the "Kosden by AeroTech" loads I-301 white. I550-red or the J-740-green.
These are actually AT propellant. 301 white lightening is virtually identical thrust curve as the I-284

AND you can do L-1 & L-2 with this case..the J-740 is a baby [barely] J .

The Kosden fast load is ONLY for a Kosden case.

Ken Allen of Performance Hobbies & Wildman both usually have them in stock. Might try calling Chris Short also.

Good luck have fun!
 
blackjack2564 said:
Rockets, If you have the Silver 640 motor...it's an AMW. If it's gold, Kosden.

AMW case you can fly the "Kosden by AeroTech" loads I-301 white. I550-red or the J-740-green.
These are actually AT propellant. 301 white lightening is virtually identical thrust curve as the I-284

AND you can do L-1 & L-2 with this case..the J-740 is a baby [barely] J .

The Kosden fast load is ONLY for a Kosden case.

Ken Allen of Performance Hobbies & Wildman both usually have them in stock. Might try calling Chris Short also.

Good luck have fun!
Click to expand...

Now that is the answer to my question! Yeah, mine is silver.
And thank you for the answer!!



Thanks,
 
Aerojet Rocketdyne is offering summer internships on the RS-25 liquid rocket engine with additive manufacturing shared by the space shuttle next summer over this project at university. To the younger Andrew, if you have the opportunity to pursue a college degree in mechanical, aerospace, or electrical engineering do it if you want it. And if the college offers SEDS or IREC competitions with HPR rocketry, if you win you get a awesome job opportunity. If they don't offer it start the club with friends and try it. These internships are a paid training program with usual later hire on status. Mechanicals will deal with spacecraft propulsion systems.
 
Excitement and enthusiasm are great things. And it’s awesome he has a supportive club.
 
rockets said:
Now that is the answer to my question! Yeah, mine is silver.
And thank you for the answer!!

Thanks,
Click to expand...

A small addition to CJ's note: the Kosdon and AMW cases are functionally equivalent...IE the ID of the case and the internal snap ring-to-snap ring length is the same. The AMW case has the external thrust ring.

Internals are definitely where it gets wonky. The Kos 640 and AMW 640 nozzles have the same throat size, but different lengths, AMW has a liner step, etc. The forward bulkheads use the same size O-rings and may use the same delays, but that's where the similarities end.

While the 38-640 hardware is a really great size (can do L1 and L2 as CJ mentioned), it's likely the most difficult hardware with current load availability to make work as certified by NAR/TRA. (To further complicate, Gorilla loads fit but use a different bulkhead).
 
Andrew_ASC said:
I don't care how many rockets this younger guy destroys. That's part of the learning process. I've destroyed three this year to varying levels of destruction as an adult learning the hobby. This isn't an easy hobby to acquire. We don't need another case of RocketryBen were a younger interested talented individual is denied the opportunity to learn by a bunch of spiteful old geezers. Not all people on this planet are able to shrug off bullies well. You know aviation smiled at fourteen year old kids. People in aviation had the respect to treat others with dignity and recognize the next generation of flyers to help expand the community, because its numbers were so small. Why can't rocketry have that same feeling to it? If you are concerned about a fourteen year old flying high power then don't be mean, embrace the opportunity to mentor him and make sure he flies safely. Sadly a lot of people on this planet are rather blunt and rude about things and as an individual with a dream you must learn to shrug off the naysayers comments and try to achieve that dream anyways.

There were fourteen year olds pursuing a mechanical engineering degree at UTC. Guess what? People were freaking mean to that kid. DARPA recently hired him. DARPA... Kid had enough spunk to keep going towards his dream and ignore snarky judgements. Don't give up no matter how mean people are.
Click to expand...

So, you have had three rocket destroyed this year? That is proof that someone needs a mentor to walk them through prepping and flying their rocket.




Sent from my iPhone using Rocketry Forum
 
First off. Two rockets were SEDS USRC 2017 competition rockets. TRA record attempts. Scratch build MD. No experience No mentors. One had an interstage implosion. Nothing to do with the "failure to prep rocket", and the other had a CATO on sustainer stage due to inexperience with HEI. Chattanooga still has no HPR mentors interested in helping the university. If you would like to mentor we would gladly appreciate it. We drove from Tenessee to Utah in three days. Then Virginia months later with a second rocket. Most teams fly once. Then to Florida and placed third by simply exceeding minimum competition requirements to design around. On a single stage when the other stage CATO'd. Sixty Eight other teams did not even finish or fly rocket. Twenty only flew a rocket. Very few recovered anything at all. TTU used the wrong altimeter and was disqualified. SEDS doesn't give a **** if your rocket is a crumpled pile of flaming sh*t at the end of a flight by a point system as long as APRA altimeter is safely recovered. The custom nosecone I designed survived and so did another team member's AV bay along with my design of booster airframe tube. Sustainer went smaller pieces than confetti post CTI Cato. point system is rigged for altitude. And bonus granted for exceeding it. If your altitude is high enough you can write off a stage and you still win by points.

Purdue also attempted 20,000 ft plus on 640 N-s and failed to recover their rocket. They didn't launch a second. You can make fun us some more. UTC USRC is open for mentors. None wanted too. And we nearly up blew sh*t. Imploded stuff. And learned by doing. The best mentors we had were the RSOs. Terry and Bruno walked off without mentoring. So we learned the hard way and it was humbling. Didn't even know one bad hawk existed. My cert rocket shock cord snapped. Got all pieces back in fly able condition. Don't use random paracord. Not all are equal. YES we could use a mentor. Would you like to mentor next year's team? This thread was suppose to be about 38/640 motors. Not SEDS rockets or how college teams suck and destroy stuff from zero experience.
 
Andrew_ASC said:
First off. Two rockets were SEDS USRC 2017 competition rockets. TRA record attempts. Scratch build MD. No experience No mentors. One had an interstage implosion. Nothing to do with the "failure to prep rocket", and the other had a CATO on sustainer stage due to inexperience with HEI. Chattanooga still has no HPR mentors interested in helping the university. If you would like to mentor we would gladly appreciate it. We drove from Tenessee to Utah in three days. Then Virginia months later with a second rocket. Most teams fly once. Then to Florida and placed third by simply exceeding minimum competition requirements to design around. On a single stage when the other stage CATO'd. Sixty Eight other teams did not even finish or fly rocket. Twenty only flew a rocket. Very few recovered anything at all. TTU used the wrong altimeter and was disqualified. SEDS doesn't give a **** if your rocket is a crumpled pile of flaming sh*t at the end of a flight by a point system as long as APRA altimeter is safely recovered. The custom nosecone I designed survived and so did another team member's AV bay along with my design of booster airframe tube. Sustainer went smaller pieces than confetti post CTI Cato. point system is rigged for altitude. And bonus granted for exceeding it. If your altitude is high enough you can write off a stage and you still win by points.

Purdue also attempted 20,000 ft plus on 640 N-s and failed to recover their rocket. They didn't launch a second. You can make fun us some more. UTC USRC is open for mentors. None wanted too. And we nearly up blew sh*t. Imploded stuff. And learned by doing. The best mentors we had were the RSOs. Terry and Bruno walked off without mentoring. So we learned the hard way and it was humbling. Didn't even know one bad hawk existed. My cert rocket shock cord snapped. Got all pieces back in fly able condition. Don't use random paracord. Not all are equal. YES we could use a mentor. Would you like to mentor next year's team? This thread was suppose to be about 38/640 motors. Not SEDS rockets or how college teams suck and destroy stuff from zero experience.
Click to expand...
Have you tried contacting the clubs near Nashville for assistance, mentors may be willing to travel to Chattanooga from that area, maybe not on demand but frequently enough to provide direction since its only a couple of hours each way.

FYI I grew up near Chattanooga attending two area high schools (Rossville which is now gone, and Lakeview-Ft.Oglethorpe, my ladt two years were at Lebanon HS near Nashville) before moving to Nashville area after my Father graduated UTC.
 
The professor had provided two mentors and one supposedly had an L-2 about three months into it. The other seemed obsessed with LPR and R candy. Both walked off the project about a week contact during first semester during design, leaving us to figure it out from scratch as we were already figuring it all out. Everything from design, OR, launchpad, electronic controller, electronics selection, regulations, starting clubs, picking materials, methods, waiver, certifications, tracking, licenses, telemetry, airspace, and actual construction then flying. So it was all on us. I wouldn't doubt if the team as a whole about 1000+ hours or more into it. Next year's team can worry about outreach to a mentor.
 
The team leader went through a phone book and active NAR/TRA members weren't really interested. One of the greatest hurdles was juggling launch sites and dates just to go past 20,000ft. The only prior experience I had was like three C motors as a little kid. Flight experience with Cessnas helped with the airspace. The rest felt foreign. OR wasn't bad. HAm exam was brutal. Getting owned on a interstage design at Mach and half was well humbling when you have had zero prior experience and watched a stable rocket suddenly vaporize due to stage wobble on stage separation.
 
Don't make the interstage motor overhang too short. Don't have an interstage reduce diameters with a hollow connection. There wasn't a book on that.
 
If you were in over your head, why proceed?

your argument is logically flawed. You did not need to fly, you are ignoring the option to not.
 
DavidMcCann said:
If you were in over your head, why proceed?

your argument is logically flawed. You did not need to fly, you are ignoring the option to not.
Click to expand...

Senior interdisciplinary courses must be taken sequentially and passed sequentially. Otherwise students will repeat a YEAR of college. So the saga with the rocket began. And the RSOs cleared our rockets to fly.
 

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