rtroup 1 #1 July 14, 2004 Why don't we use microline for closing loops. Is it just over kill?(insert philosophical quote here) Quote Share this post Link to post Share on other sites
FrogNog 1 #2 July 14, 2004 I don't think it would do what we want it to. Peak and average tension on the main closing loop is pretty low, so a super-duper-strong line isn't necessary. We want to keep the container closed as securely as possible until deployment time, then open the container as reliably as possible. [From here on, I'm in 100% guess land.] That suggests a line that interfaces properly with the short pin we use on throw-out and pull-out systems to produce a consistent grip with a medium pull force. I guess Type 2 A cord does this well because it's fat (so more yarns lay against the pin). Stretchiness may also have some effect. I don't know anything about the coatings various lines are treated with, and how they might affect required pin withdrawal forces. -=-=-=-=- Pull. Quote Share this post Link to post Share on other sites
AggieDave 6 #3 July 14, 2004 Nevermind that microline would tear up faster due to friction from a pullup chord, sort of like the closing loop for a Sigma tandem.--"When I die, may I be surrounded by scattered chrome and burning gasoline." Quote Share this post Link to post Share on other sites
diablopilot 2 #4 July 14, 2004 QuoteNevermind that microline would tear up faster due to friction from a pullup chord, sort of like the closing loop for a Sigma tandem. I find just the opposite. I use used Spectra from old linesets for mine. The last for ever and are not too slick as the coating has worn. Type 2A cord is not resistant to abrasion and fails easily I find.---------------------------------------------- You're not as good as you think you are. Seriously. Quote Share this post Link to post Share on other sites
PhreeZone 20 #5 July 14, 2004 Mike from Jumpshack made me a 1000 lb dacron closing loop last year at WFFC. 200+ jumps latter I'm yet to see the first fiber fray on it.Yesterday is history And tomorrow is a mystery Parachutemanuals.com Quote Share this post Link to post Share on other sites
mjosparky 4 #6 July 15, 2004 What you make a main closing loop out of is not as important as how long you make it. I would say at least 50% of the rigs on a drop zone have the loops to long to make closing easier. SparkyMy idea of a fair fight is clubbing baby seals Quote Share this post Link to post Share on other sites
AggieDave 6 #7 July 15, 2004 QuoteI find just the opposite. I use used Spectra from old linesets for mine. The last for ever and are not too slick as the coating has worn. Huh. And I've seen Sigma closing loops last 15 jumps because a packer couldn't find his packing tool and was using a pull-up chord. Compared to a few hundred jumps when packed using a packing tool.--"When I die, may I be surrounded by scattered chrome and burning gasoline." Quote Share this post Link to post Share on other sites
riggerrob 643 #8 July 15, 2004 QuoteQuoteI find just the opposite. I use used Spectra from old linesets for mine. The last for ever and are not too slick as the coating has worn. Huh. And I've seen Sigma closing loops last 15 jumps because a packer couldn't find his packing tool and was using a pull-up chord. Compared to a few hundred jumps when packed using a packing tool. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> 400 pound Spectra (aka Cypres cord) is standard on reserve loops, while 1500 pound Spectra is standard for Strong tandem closing loops. Sport rigs can use something in between, typically old 700 or 800 pound Spectra suspension lines. I think the main reason we used to use Type IIA was tradition. Back in the good-old-days, we always had miles of 550 cord (from military surplus round canopies) laying around and it was s simple matter to "gut" it and get a hundred free closing loops. In comparison, switching to a Spectra closing loop automatically lowers pull force by 5 pounds, but I have to agree with Sparky, that the majority of closing loops - in service - are the wrong length. Quote Share this post Link to post Share on other sites
darkwing 5 #9 July 15, 2004 Lowering the pull force by 5 pounds is something I think you should generally avoid on a main loop... -- Jeff My Skydiving History Quote Share this post Link to post Share on other sites
riggerrob 643 #10 July 15, 2004 QuoteLowering the pull force by 5 pounds is something I think you should generally avoid on a main loop... >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> I was primarily referring to lowering reserve ripcord pull forces by installing Cypres loops (400 pound Spectra). The quickest - and most reliable way - to increase main pull force is to shorten the closing loop. Choice of line type is insignificant if the loop is too long. Far too many sport jumpers use main closing loops that are WAY too long/too loose. Their excuse is that the long loop is easier to close. Few of them realize how close they are to a premature deployment. Quote Share this post Link to post Share on other sites
masterrig 1 #11 July 15, 2004 I've got to agree with you and Sparky, about loop lengths. When I can see the bagged parachute oozing out between the flaps or spring-loaded pilot chutes 'peeking' their caps between the flaps on student rigs. I have gotten the same 'excuse'; "It's easier to close!" Good grief! Reaching a hand in under the side flaps, while keeping a bit of tension on the pull-up cord and pushing the bagged parachute material out, toward the sides of the container helps make closing easier. It's also 'easier' on the flaps and grommets. There are all kinds of little 'tricks' to make packing easier and closing loops the 'proper' length. Chuck Quote Share this post Link to post Share on other sites
usskydiver 0 #12 July 15, 2004 I jump a POP and I prefer to use Spectra for my closing loops. I also ensure my loop is tight enough for our packers to make the occasional snide remark. Tim T. Team Paraclete Quote Share this post Link to post Share on other sites
FrogNog 1 #13 July 15, 2004 OK, looks like I was totally wrong. I'll experiment with spectra closing loops shortly.* (The Cypres reserve loop material looks like a fine place to start.) * Why? I don't know. I'm just compelled to do these things. -=-=-=-=- Pull. Quote Share this post Link to post Share on other sites
payback462 0 #14 July 16, 2004 i use 1500lb spectra for my closing loop. i make it double sided so that when one side wears out i just take it out and turn it around! and if both brake i can just quickly grab one of the loops for a strong tandem. plus you dont need a washer on the loop then Quote Share this post Link to post Share on other sites
riggerrob 643 #15 July 16, 2004 QuoteOK, looks like I was totally wrong. I'll experiment with spectra closing loops shortly.* (The Cypres reserve loop material looks like a fine place to start.) >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Cypres reserve loop material works great for closing reserves, but is not nearly tough enough for mains. Few riggers expect a Cypres reserve closing loop to last more than two pack jobs and many fanatical riggers replace Cypres loops at every reserve repack. * Why? I don't know. I'm just compelled to do these things. Quote Share this post Link to post Share on other sites
mjosparky 4 #16 July 16, 2004 QuoteFew riggers expect a Cypres reserve closing loop to last more than two pack jobs and many fanatical riggers replace Cypres loops at every reserve repack. Who are you calling fanatical? SparkyMy idea of a fair fight is clubbing baby seals Quote Share this post Link to post Share on other sites
alan 1 #17 July 22, 2004 I questioned Sandy Reid of RI about this several years ago. They cost more. They will far outlast the gutted 550 Type II if used properly. They will be dangerous if not used properly. Basically the packer has to put a finger over the loop when removing the pullup chord and should not feel any heat from friction when the pullup chord is removed. If heat is felt, there may be hidden damage to the Spectra between the pin and the loop, even when care is taken to pull it under the pin. I have one made of 800# Spectra that has 500 or more jumps on it. I'm careful with the pullup chord and I treat it with a little silicone every now and then. I keep the loop pretty tight and have had no pin slipping issues. The old reserve loops before the CYPRES loops became the norm were just Spectra and the same loops will work just fine on the main...........just don't burn them with a careless zip of the pullup chord.alan Quote Share this post Link to post Share on other sites
riggerrob 643 #18 July 22, 2004 QuoteI questioned Sandy Reid of RI about this several years ago. They cost more. They will far outlast the gutted 550 Type II if used properly. They will be dangerous if not used properly. Basically the packer has to put a finger over the loop when removing the pullup chord and should not feel any heat from friction when the pullup chord is removed. If heat is felt, there may be hidden damage to the Spectra between the pin and the loop, even when care is taken to pull it under the pin. I have one made of 800# Spectra that has 500 or more jumps on it. I'm careful with the pullup chord and I treat it with a little silicone every now and then. I keep the loop pretty tight and have had no pin slipping issues. The old reserve loops before the CYPRES loops became the norm were just Spectra and the same loops will work just fine on the main...........just don't burn them with a careless zip of the pullup chord. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> You can burn any closing loop - made of any material - by removing your pull up cord too quickly. sloppy workmanship Quote Share this post Link to post Share on other sites
cybervagrant 0 #19 July 25, 2004 My friend, who just showed me how to pro pack her stilleto, told me to move the pull cord under the pin before removing it to lessen the wear on the closing loop. Cheers, Cyber Whoops, is my ignorance showing again? Quote Share this post Link to post Share on other sites
masher 1 #20 July 27, 2004 Doesn't everybody do that? . That's how I was taught...-- Arching is overrated - Marlies Quote Share this post Link to post Share on other sites
Chrisky 0 #21 July 27, 2004 Nope, not everybody. I was taught to put my finger on and to pull the chord out gently, as it used to be damn hard to get that chord under the loop on that student canopy. Now i use a power tool with a sleek chord and put it under the pin before extraction. But if you look around, you will find some people ripping out the pullup chords like they intentionally want to rip the loop. (It actually is a handy method to remove those hard-knotted broken rubber bands from the dbag).The mind is like a parachute - it only works once it's open. From the edge you just see more. ... Not every Swooper hooks & not every Hooker swoops ... Quote Share this post Link to post Share on other sites
masher 1 #22 July 28, 2004 QuoteNope, not everybody. I was taught to put my finger on and to pull the chord out gently, as it used to be damn hard to get that chord under the loop on that student canopy. I never had a problem doing that on student canopies, or an canopy for that matter... oh well...-- Arching is overrated - Marlies Quote Share this post Link to post Share on other sites
Chrisky 0 #23 July 28, 2004 Well, you know, when you learn how to pack, packjobs tend to be a bit uneven and bulgy... Makes a well-fitting loop seem a bit tight... I just got reminded of that when i got my new rig with my new canopy... These first few packjobs made me question my packing abilities... Now it's all back to routine again.The mind is like a parachute - it only works once it's open. From the edge you just see more. ... Not every Swooper hooks & not every Hooker swoops ... Quote Share this post Link to post Share on other sites
