Jolly Logic Chute Release

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rcktnut

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A few more things here, after cutting the bungee to size I melt the cut ends. Bungee frays a little and melting the ends will keep it nice and neat. I also like to get my bigger chutes packed at home so after packing I use a strip of Velcro to wrap around the packed chutes. It keeps them ready to go and you can also adjust the CR with the Velcro on.
 

o1d_dude

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A few more things here, after cutting the bungee to size I melt the cut ends. Bungee frays a little and melting the ends will keep it nice and neat. I also like to get my bigger chutes packed at home so after packing I use a strip of Velcro to wrap around the packed chutes. It keeps them ready to go and you can also adjust the CR with the Velcro on.
Great idea!
 

ZEDL1

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Yes, it was the braided elastic that I was referring to in my question. Thank you both for your help. Very much appreciated.
Jim
 

Winston

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Maybe this has been discussed elsewhere, but when HPR nylon 'chutes are laid out with gores stacked on top of each other and then grabbed between thumb and index finger just above the base of the 'chute, the base is considerably larger in diameter than the grabbed section because of the folded hemline and the shroud line attachment points. This would, I'd think, keep the JLSR from slipping off during descent and would allow the upper section of the 'chute (most of the 'chute) to unfurl and act a bit like a drogue 'chute during the descent.

Is there a reason why this method of 'chute reefing isn't used?
 

Mach_Seven

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I too have experienced the Chute Release “failure” of not turning it on before walking away from the pad.

Talk about feeling stupid when you find the chute bundle neatly tied up next to the remains of your rocket...and your JLCR is NOT turned on...”Go Fever” strikes again.
"Go Fever" for me was fatigue, dehydration, and sunburn. My Iris fell from 3700' with nothing but a streamer deployed due to the band digging into the chute too much. I also didn't powder it with corn starch between flights and felt that tackiness coming back. But I was by myself with no help and no shelter and it's like "I gotta get this thing in the air before I die from exposure out here..."

The Iris is fine, by the way. Zero damage. I think the tailcone retainer saved it's life at impact.
 
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Mike Haberer

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Most AT motors' delay charges can be drilled out to shorten the delay timing.
Not exactly. There are 20 Single Use motors that are not delay-drillable, 3 LMS motors that you can pick a set delay and 35 DMS motors that are delay-drillable. 23 out of 58 are not drillable - 40%.
 

Mike Haberer

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I orient the pin at a tangent to the bundle.
If the pin isn't at nearly a tangent, the band isn't tight enough. Always pack, ground test and repack the same way if the CR opened. If not. repeat with a tighter pack or shorter band.
 

dhbarr

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EDIT: Ignore my untimely response to an old post.
 

TomBroad

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Amidst this long discussion about rigging the Jolly Logic, the one item I have not seen mentioned is the knot used to secure the tether. With deference to @John Beans — I have been climbing and caving for many years, and the simple overhand knot on the tether (as shipped) is NOT secure in such a stiff and slippery cord (see first photo). You paid big $$$ for your JL so don’t lose it because the tether came untied.
My recommendation is to re-tie the tether using a “Grapevine” (aka: “Double Fisherman’s”) knot (second photo). This is a self-locking knot - the harder you pull it, the more secure it gets. It also avoids sharp bights which are a problem with Kevlar. It’s a PITA to tie in this cord, but worth the piece of mind. To learn how to tie this, just Google “grapevine knot.”
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BB7841A9-1743-4E90-B0B8-27BAF2E650A5.jpeg
 
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Handeman

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Amidst this long discussion about rigging the Jolly Logic, the one item I have not seen mentioned is the knot used to secure the tether. With deference to @John Beans — I have been climbing and caving for many years, and the simple overhand knot on the tether (as shipped) is NOT secure in such a stiff and slippery cord (see first photo). You paid big $$$ for your JL so don’t lose it because the tether came untied.
My recommendation is to re-tie the tether using a “Grapevine” (aka: “Double Fisherman’s”) knot (second photo). This is a self-locking knot - the harder you pull it, the more secure it gets. It also avoids sharp bights which are a problem with Kevlar. It’s a PITA to tie in this cord, but worth the piece of mind. To learn how to tie this, just Google “grapevine knot.”
I lost my first JL on the 4th flight. Since then, I've replaced the included tether with a 1/8" Kevlar tether tied with a much better knot. Haven't lost one since. You're grapevine knot would have probably solved the problem, but I just feel better with the larger and stronger Kevlar.
 
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