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  1. #781
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    This video is from a while back, but I thought I'd post it in this thread to get some feedback. The rocket is an Estes Sahara. Almost every time I use the JLCR with this rocket, the chute fails to open the way it should. No problems on any other rockets. I have the chute attached to the stock shock cord about a foot aft of the payload section (transition). I've noticed in other videos that the stock shock cord gets pretty wound up during decent. I pack my chute the same as I do any other time with any other rocket. I'm wondering, has anyone else had this issue with the chute failing to inflate on rockets that have transitions when using the JLCR? Would it help if I simply attached the chute to the bottom of the transition, as per instructions? One other reason I'm looking for feedback is because I'm building a LOC Expediter which has the exact same design as the Sahara, only much bigger and more expensive. It has a 20 foot, 1/2" nylon harness with a swivel on one end, so that should at least minimize the harness from getting wound up. Maybe I should attach my JLCR wrapped chute directly to the transition instead of a few feet below it. What say you?
    https://youtu.be/u9GOKCbvmBg

    NAR# 100470
    L1- 10/18/15 LOC IV CTI H163
    L2- 4/16/16 Madcow PAC-3 CTI J285

  2. #782
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    5th June 2010
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    Well done video.
    It looks like something (either shroud lines or shock cord) is wrapped around the chute outside of the band. So after release the chute still has a loop of something around it. Anyone else see that?


  3. #783
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    Thanks John. I think what you're seeing is the yellow Kevlar string I used when I replaced the original tether. Here's an up close video screen shot...
    Click image for larger version. 

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    NAR# 100470
    L1- 10/18/15 LOC IV CTI H163
    L2- 4/16/16 Madcow PAC-3 CTI J285

  4. #784
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    3rd August 2011
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    Reed City, Michigan
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    John, is there a point where there is too much tension for the pin to release the band?

  5. #785
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    13th October 2014
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    Quote Originally Posted by John Beans View Post
    Well done video.
    It looks like something (either shroud lines or shock cord) is wrapped around the chute outside of the band. So after release the chute still has a loop of something around it. Anyone else see that?
    There might be. I got a couple screen captures of the video. At time 1:21 the chute looks clear. But at 1:25 and 1:26 there appears to be something else around the chute. See what you think...

    Click image for larger version. 

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    NAR 98451 L2; MDRA 024; BARC 001 (President)
    L1 - Madcow Honest John 2.6, CTI H163
    L2 - Madcow Level 2, CTI J335
    Mile High Club 5,650 ft (07/16/16)

  6. #786
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    Here's another screenshot of just moments before it landed. Obviously the Chute Release band is no longer wrapped around the chute, so it (Chute Release) didn't fail me. The shroud lines are still nicely tucked and rolled inside the chute, the chute just failed to catch air. It's only THIS rocket. It happened before, with a Fruity Chute. So I thought I'd change chutes. Same thing. I'll post a link to that video as well. In that flight, the chute opened just in time to get the rocket slowed before it landed.
    Click image for larger version. 

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    https://youtu.be/NTH6pVTRw6M
    NAR# 100470
    L1- 10/18/15 LOC IV CTI H163
    L2- 4/16/16 Madcow PAC-3 CTI J285

  7. #787
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    Quote Originally Posted by John Beans View Post
    Well done video.
    It looks like something (either shroud lines or shock cord) is wrapped around the chute outside of the band. So after release the chute still has a loop of something around it. Anyone else see that?
    Yes, Is that the line used to secure the chute release so it stays on the harness and not leave the rocket when the rubber band is released?
    I also take it the venue is someplace where it's not too cold? I'm sure all have witnessed chutes that "just don't fill" because they're too stiff from the cold. Kurt

  8. #788
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    Quote Originally Posted by ksaves2 View Post
    Yes, Is that the line used to secure the chute release so it stays on the harness and not leave the rocket when the rubber band is released?
    I also take it the venue is someplace where it's not too cold? I'm sure all have witnessed chutes that "just don't fill" because they're too stiff from the cold. Kurt
    That's correct. I needed to replace the tether on the CR, and I replaced it with a thicker and slightly longer Kevlar thread. As far as weather, the first video I posted (chute never opened) was on New Years Day. It was above freezing. I know that because my girlfriend refuses to join in a launch if it's below freezing. The video with the Fruity Chute was from last May. So I know that temperature isn't a factor.
    NAR# 100470
    L1- 10/18/15 LOC IV CTI H163
    L2- 4/16/16 Madcow PAC-3 CTI J285

  9. #789
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    It appears that there was still something wrapped around the chute when it was on the ground. It is clearly not the shock cord so if you're sure was not the shroud lines then maybe it was the tether.

    NAR Level 2 #96210

  10. #790
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    Quote Originally Posted by Nathan View Post
    It appears that there was still something wrapped around the chute when it was on the ground. It is clearly not the shock cord so if you're sure was not the shroud lines then maybe it was the tether.

    Yeah, that's the tether. It wasn't tight by any means. I know it doesn't have to be either to keep the chute from opening. I'm just wondering why it only happens with this rocket. I don't know if having the payload section (extra mass) causes the rocket to descend differently than a rocket that just pops the NC.
    NAR# 100470
    L1- 10/18/15 LOC IV CTI H163
    L2- 4/16/16 Madcow PAC-3 CTI J285

  11. #791
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    19th January 2009
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    It seems like the shock cord is so twisted up that it gets shorter and pulls the chute close to the transition and that may be what prevents it from catching air.

    I would move the chute to about 2 ft from the transition and add a ball bearing swivel to the fin can so it can spin without twisting up the shock cord. Then when the JLCR lets go, the chute will be further from the upper section, it should catch air and open without a problem.
    Handeman

    TRA #09903 L3 :D 3/29/2015

    "If you don't use your head, you have to use your feet!" my Dad

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  12. #792
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    26th November 2009
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    Quote Originally Posted by Handeman View Post
    It seems like the shock cord is so twisted up that it gets shorter and pulls the chute close to the transition and that may be what prevents it from catching air.

    I would move the chute to about 2 ft from the transition and add a ball bearing swivel to the fin can so it can spin without twisting up the shock cord. Then when the JLCR lets go, the chute will be further from the upper section, it should catch air and open without a problem.
    Yup, what he said. Change your configuration and I bet the problem will go away. Weirdest chute behavior I've ever seen besides the usual Hail Mary recoveries where the main chute hangs in the tube and pulls out just before the crash to
    save the rocket is a USR Banshee I made into a long neck rocket with an MAWD dual deploy. The configuration was such that with drogue deployment, the rocket glided down aft end first dragging the upper bay and the 12" drogue behind it.
    It would circle down, climb a bit, stall and would repeat the cycle till it hit the main deployment altitude. The main would blow horizontally many times and the whole thing would swing down like a pendulum. The configuration was just so, so it
    flew this way every flight. Had a motor failure that took that rocket down so I built another. I was hoping it would do that same thing but expected it wouldn't. It doesn't.

    A one time event was with the mid power Apogee Rising Star rocket. It was 10 years ago and I used the stock plastic chute. I launched it way up there on I believe an F motor and the apogee event occurred. That thing was coming down fast and I was
    asked if the rocket was "dual deploy"? It looked like the chute had streamered but it didn't appear to have torn lines. Rocket body was below the chute. As it got lower, it appeared the body of the chute was puffed out a bit but the open end was constricted. I did not use a reefing ring as I didn't know what that was back then. The chute then gently billowed open perhaps around 500 feet and I didn't have much of a walk to recover it. When I inspected it, nothing. No burn holes, torn lines
    (remember it was a stock plastic chute) or any damage whatsoever. It was sweatshirt weather too so it wasn't unduly cold.

    Only thing I could figure is the conditions were just right that the end of the chute was "held" closed a bit by the airflow going up and around the canopy. The canopy lines were stretched with the sustainer underneath. I noted as it got lower, the canopy quivered and then opened up the rest of the way gently.

    I'll take it. It was a "natural" dual event process that was interesting to witness. Now that behavior was never seen again with that rocket. I suspect that perhaps a gentle horizontal gust of wind pertabated the the system that disrupted the canopy to open.

    Stupidhead here suggest not to put the chute release AROUND the chute protector. Do something like duct tape to hold the protector in more or less one place once threaded on the harness. or knot the protector on the harness so once it's blown out into the breeze, the JLCRchute pack is totally clear from the protector. Heck, once the charge goes off, you don't need the protector anymore. Why do it this way? If you wrap the band around the
    chute protector, a lot of the nomex protectors are stiff. I tried it once and the chute never made it out of the crinkled, stiff protector even though the band was released.

    I used to "attach" a length of kevlar thread to a chute protector and put a loop on the end of the thread and then thread that on the harness.
    I stopped that a long time ago, even before the JLCR 'cause the only thing that kevlar thread leader did was wrap around and tangle everything else. Just open up the button hole on the "store" bought protectors and thread them on
    your harness.

    Look at Mr. Bean's video at his store, you can't go wrong with his method. Kurt

  13. #793
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    5th June 2010
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    Have to guess at this point.

    1. Maybe too long of a tether?

    2. Maybe try rolling your chute into a smoother, tighter (and less fluffy and catchy) bundle? What you've got is pretty good, but it could be tighter.
    While it might seem like a fluffy bundle will catch the air better, those flaps of loose fabric tend to flop and drape over and clamp down on lines in unpredictable ways. They are like a variable you can't control. My favorite ground tests are when the chute "pops apart" upon release. Shrouds inside, and a roll or a z-fold (or some of both).

    3. Also consider trying a "skirt reef," where you let the length of the chute flap like a drogue, and just band around the base of the chute. Needs to be tight, and pass the shake test prior to flight. Especially useful for small diameter rockets.

  14. #794
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    25th July 2015
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    Some great insight and input here guys. Thanks! I'll try a few different suggestions and see what works best.
    NAR# 100470
    L1- 10/18/15 LOC IV CTI H163
    L2- 4/16/16 Madcow PAC-3 CTI J285

  15. #795
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    Quote Originally Posted by Woody's Workshop View Post
    John, is there a point where there is too much tension for the pin to release the band?
    Not if you use the elastic bands provided. If you were to use plastic zip ties you could bind it, or even break the pins.

  16. #796
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    I've never used anything but the bands provided. And I've stretched a couple pretty tight. Never had a problem with one not getting released properly. Using my CR along with my Altimeter 3 is no doubt my favorite way to launch a rocket.
    NAR# 100470
    L1- 10/18/15 LOC IV CTI H163
    L2- 4/16/16 Madcow PAC-3 CTI J285

  17. #797
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    17th January 2011
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    Question has anyone else had problems with the rubber bands breaking in cold weather flights. Today in WI temp was about 30 when I flew and the rubber band broke a friend of mine had his second flight with his JLCR and both of his flight the band broke. I myself have had about 6 flights all in warm weather with no problems until today. Should the rubber band be replaced each flight?
    TRA 2225
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  18. #798
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    I don't think replacement after each flight is necessary, but as I commented earlier in this thread somewhere, I have been noticing that the bands eventually get damaged and break. I've inspected them carefully before flights, and won't use the band after it has a couple of nicks or cuts in it. So far, I've seen them break during setup or testing, but not on an actual flight.
    Rick
    URRG, MARS
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    http://www.rocketreviews.com/rick-barness-page.html

    There is a theory that states that if anyone figures out why the universe is for or why it is here, it will suddenly disappear and be replaced by something even more bizarrely inexplicable.
    There is another theory that says this may have already happened...



  19. #799
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    Quote Originally Posted by EXPjawa View Post
    I don't think replacement after each flight is necessary, but as I commented earlier in this thread somewhere, I have been noticing that the bands eventually get damaged and break. I've inspected them carefully before flights, and won't use the band after it has a couple of nicks or cuts in it. So far, I've seen them break during setup or testing, but not on an actual flight.
    I was about to say exactly this. Treat it as a maintenance item. If you find they are too small for larger chutes, don't forget you have larger bands under the tray in the product box.

  20. #800
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    Also, I'd be happy to drop bands in the mail if you run out. Just email me at Jolly Logic.
    As I mentioned at NARCON, I'm also going to be working on a bag accessory to complement Chute Release.

  21. #801
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    17th January 2011
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    John
    I have always used the larger bands. But for what ever reason the chute opened at about 2800' like it should after motor ejection. when I got to the rocket the band was broke at the servo end and pin was gone. So I am think the band broke sometime before deployment or at deployment. and when JLCR servo did its job the pin fell out of device. I sure like the Jolly Logic 2 it shows a lot of fun info.
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  22. #802
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    17th January 2011
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    Hi all
    I ordered some replacement bands and servo pins a couple of days ago. Well there here today. Thanks John for the very fast service. Great products and fast service what more could we ask for.
    TRA 2225
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  23. #803
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    I would suspect if you are breaking bands they are too small for the chute. All bands break if you they are stressed to far.


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  24. #804
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    Quote Originally Posted by redleder View Post
    I would suspect if you are breaking bands they are too small for the chute. All bands break if you they are stressed to far. Sent from my iPhone using Tapatalk Pro
    To be fair, there's a fairly large difference in size between them. In my experience, the larger one is only snug enough on chutes starting at about 36"; below that I have to use the smaller band. Obviously, some of it depends on how I've folded the chute for the specific rocket in question, though most of my chutes are thin-mil nylon. So, I only use the larger band on a few rockets, and use the smaller one a lot. On 24 or 30" thin mil chutes, it might be stretched a bit, but the larger one isn't tight enough. There are only so many options...
    Rick
    URRG, MARS
    Tripoli #15706
    http://www.rocketreviews.com/rick-barness-page.html

    There is a theory that states that if anyone figures out why the universe is for or why it is here, it will suddenly disappear and be replaced by something even more bizarrely inexplicable.
    There is another theory that says this may have already happened...



  25. #805
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    Quote Originally Posted by EXPjawa View Post
    To be fair, there's a fairly large difference in size between them. In my experience, the larger one is only snug enough on chutes starting at about 36"; below that I have to use the smaller band. Obviously, some of it depends on how I've folded the chute for the specific rocket in question, though most of my chutes are thin-mil nylon. So, I only use the larger band on a few rockets, and use the smaller one a lot. On 24 or 30" thin mil chutes, it might be stretched a bit, but the larger one isn't tight enough. There are only so many options...
    I use a wad of wadding (hah) or insulation to provide the extra stretch for small chutes.

    "I'm at least 70% confident about whatever I say (90% of the time)"- college me

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