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Rope/knot/splice load testing


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#1601 allen

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Posted 06 August 2014 - 08:20 PM

^^ you probably know but you have to get an IR gun pretty close to read the temp of what you want.  The one I have is not very good and has an 8:1 spot size meaning if you want to measure a 1/4  inch spot, you can be 2 inches away.  I saw a guy on Youtube try and show that the tip of a knife heated with a belt sander didn't get hot with the same IR gun I have about a foot away.  I repeated the experiment and basically melted the metal on the knife red hot.



#1602 Estar

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Posted 06 August 2014 - 08:48 PM

^^ yes, thanks, I knew it needed to be close but have never seen any specs on how close (its one of the better fluke guns) - I also have 'measured' the temp of the pieces by simply pinching the piece with my finger, and gotten 'results' at least roughly consistent with my IR gun. I have also closely/microscopically inspected the slip surface after the tests and not seen any obvious signs of melting.

 

In my above post I was really trying to say that (1) I had measured tried to measure temps, (2) my measurements were very very crude, (3) I don't think I am getting much of the piece very hot (not near melting point) but I don't know (and cannot know with my equipment) about temps right at the slip surface.



#1603 allen

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Posted 06 August 2014 - 08:54 PM

^^ I never tried to measure the temperature but I did get smoke and where there is smoke...



#1604 NHRC

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Posted 06 August 2014 - 09:31 PM

I have done a lot of break testing for super yacht running rigging. Up to 46mm sk90 cores. We noticed huge temperature differences thoughout the line at load points and around the ends of tapers.

As you say the surface physically feels warm, but we noticed that the inner core had heat damage/melting, so we can presume that inside is a lot hotter.

I am just a humble rope pusher but I guess when a line takes load it has to expell energy in some direction and heat would be an obvious transfer.

I have seen broken mainsheets from large 180ft super yachts where at the most used point, the prefeeder from the captive winch, the rope looks brown and scorched and the core is glass like.

We also noticed that the part of the rope that went through a prefeeder or fairlead on a sheet was at only 30% of its original break load. Where as the spliced end was still capable of taking full load.

We were testing a variety of ropes at a commercial hydraulic test centre in Southampton uk.

Our results were very consistent and overseen by the manufacturers.

#1605 Estar

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Posted 06 August 2014 - 10:05 PM

^^ interesting. Thanks. I wonder if this is one area where things get worse with scale. . . . More heat at a thin surface boundary and more rope mass insulating that heat from dissipating?

I never saw any smoke, nor any discoloration in my test pieces. Some of this would also depend on how fast you pulled. Because of Brion's comments early in the thread I always pulled moderately slowly, keeping within the official test spec, but in the "real world" loads often come on much faster than this.

I am aware of the heat issues related to smoking a highly loaded line around a drum, and the rope MFG's have developed special covers for those applications. I guess your pre-feeder location heat is also from external friction? Some of which apparently bleeds into the core? The bend radius results suggest you could also be getting internal fiber on fiber friction even in a 20 degree deflection. Would water cooling help?

This is an area which would require significant lab gear to test/measure properly/carefully. My personal judgement is that while it is obviously relevant to super yachts and the powerful end of racing yachts, it is probably not a major factor for most of us. Unless anyone has a clever suggestion it seems beyond my capability to make internal measurements in a highly loaded piece.

#1606 olaf hart

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Posted 06 August 2014 - 10:17 PM

The larger the diameter, the less surface area per unit of volume, so the size argument makes sense.

Except that the material is a poor conductor of heat, so it might not be operating with sudden loading.

#1607 allen

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Posted 06 August 2014 - 11:40 PM

^^ My testing was with 7/64 line but I pulled fast.  I would get a puff of smoke as the knot failed. If I pulled slowly, the knot would hold.  Pull speed is a very significant variable.  That is where I took issue with the Water Bowline testing on youtube. They pulled very slowly and it held.  In my testing it slipped and the extra tuck I took kept it from slipping.

 

There are many variables here and different modes of failure.  The way you test can determine if you excite some of these failure modes or not.

 

I have another sub topic and will post it shortly.

 

Allen



#1608 allen

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Posted 06 August 2014 - 11:47 PM

I installed some dynamic climbing rope on my traveler with great success.  Shortly after installing it, I handed the tiller to a mate and we soon after did an accidental gybe.  The last one I did split the boom (wood) but this one did no damage.  Now I can gybe faster without worry. It is a wonderful change.

 

But in the last race this orange line shed many parts of its cover and I had orange bits all over the deck.  Some of the line is down to the core.  I race once a week so this is likely the 11th race. Each race is just a tad over an hour.  The word on this when the idea was posted was that Stan Honey used this on a race to Hawaii.  Either he didn't adjust the traveler much or there is a lot of variation in the cover of these dynamic lines.

 

I still have a lot of new orange line as I bought way more than I needed due to the shorter line needs of a traveler vs a mountain climber.  When I run out of my orange line, I hope someone can help with what I should be looking for in a replacement.  @thinwater, are you listening?



#1609 Essington

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Posted 07 August 2014 - 01:37 AM

Estar, I'm also curious about the NER testing as they are using NER product, so that likely means Endura (the stuff I've been using), or maybe STS HSR (NER's version of dynex dux, the stuff I'd like to be using ... If I could get some).

Ego, none of my shackles actually move against their metal counterpart in use, so there is no chafe on the shackle, and no wear on the beckets. In the major load areas, the soft shackles have a much higher breaking strength than the metal does, so I'm comfortable with my safety factors even over the square corners. I could probably radius those edges, but I've not felt a need to yet.

#1610 Estar

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Posted 07 August 2014 - 01:58 PM

A, I have been using dynamic line a decade in both my traveler and anchor snubber. My trav line has the equiv of 10's of transpacific on it. The only time I have suffered any cover damage is chafe on the snubber in a hurricane (Lenny). So, I would suggest either the stuff you got has a particularily vulnerable cover or your trav set up is particularily hard on it. Unfortunately I got the line so long ago I don't remember specifically what it is, but it is Beal brand.

Ess, brion and NER were testing the STS line. Part of the objective was to answer some questions raised by an odd colligo dux failure, but (of course) NER preferred to test their own heat treated line rather than dux.

#1611 allen

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Posted 07 August 2014 - 02:42 PM

A, I have been using dynamic line a decade in both my traveler and anchor snubber. My trav line has the equiv of 10's of transpacific on it. The only time I have suffered any cover damage is chafe on the snubber in a hurricane (Lenny). So, I would suggest either the stuff you got has a particularily vulnerable cover or your trav set up is particularily hard on it. Unfortunately I got the line so long ago I don't remember specifically what it is, but it is Beal brand.
 

That is good to hear. I think the damage was likely done by the cam cleat.  It is a Harken 150.

 

The rope is Sterling Rope Evolution Duetto Dry Rope 8.4mm.  The damage was building but was minimally noticeable until this last race.

dynamic_rope.jpg

 

This next picture was taken before the dynamic line was installed.  The traveler is 5:1 with the block on the rail making the first turn.  There is teflon "million dollar" tape over the screws on the bronze half round.

 

traveler.jpg



#1612 Estar

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Posted 07 August 2014 - 04:15 PM

^^I agree probably the cam cleat. I have a line driver in my system, which may be a more gentle hold (but my trav loads have to be much higher), rather than cam cleats. The rest is much like yours.

Did you have no problem with cover wear before the climbing line? I had always understood climbing line had tightly woven very durable covers compared to sailing line . . . . But I could be wrong.

If I were you I would talk to both harken and beal about suggestions.

#1613 allen

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Posted 07 August 2014 - 04:30 PM

^^ I had no problem with the traveler line before switching over to climbing line.  I used some old line I had around that was probably 50 years old and yet no issues.  I have enough of the climbing line to make a couple more control lines but when that is gone I am sure not going to use the same line.  The cover is tightly woven, much tighter than yacht braid.

 

Allen



#1614 Estar

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Posted 07 August 2014 - 04:39 PM

Interesting. Beal will probably be able to give you some insight into cover durability, as that is important for climbing line. I will be curious what you learn. The stuff I have has worn like iron . . . More abrasion resistant in the snubber application than "yachting" line.

I wonder what sterling would say if you showed them your pic of their product. It's not an application they design for, but I still expect they would be surprised it shredded like that so quickly.

#1615 allen

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Posted 07 August 2014 - 09:36 PM

^^ Sterling said they had never seen a line shred like that.  They suggested a different one of their ropes, Marathon, and also suggested using single rope instead of half rope.  I had picked half rope as it would give me almost twice the stretch for a given impact load.  

 

Half rope has 31% stretch for 110kg shock load

Full or single rope has 36% stretch for 220kg shock load

 

Harken had nothing to add.  Thinks the cam cleats are pretty easy on the line.

 

Sterling might be sending me a sample.  He offered 10 meters and I need 12 so we will see.

 

I need to check that the teflon tape didn't come off.  That would be an easy explanation.  Especially given your 10 year use without issue.  I will check Saturday.

 

Allen



#1616 allen

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Posted 10 August 2014 - 02:37 AM

^^ The million dollar tape was gone and there were some edges that might have caused some problems but nothing obvious.  I spent a couple of hours cleaning things up, did some filing and sanding and reapplied the teflon tape.  Hopefully this new line will last as long as it has for @Estar.

 

Sterling is sending me a couple of different samples. I will test them and write up what I find.

 

Allen



#1617 Estar

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Posted 12 August 2014 - 12:08 PM

By the way . . . . several people have asked me about the durability/chafe resistance of the soft shackles in 'chain hook replacement mode'.  Here is a photo of one I used all this year, including in some decent strength wind up in Labrador and Greenland.  It's dirty but pretty much no chafe or wear.  This is one of my earlier 'simple stronger' designs.

 

Attached File  photo.JPG   147K   45 downloads

 

 



#1618 Essington

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Posted 23 August 2014 - 05:09 PM

I would be interested in your dimensions/calculations.


My technique for making the strong soft shackle goes something like this:

1) cut your line to the required length: (shackle length + tail length) * 2
2) create the noose crossover so that the noose is just the right size when the bitter ends are even with each other
3) with the bitter ends even with each other, measure back from the bitter ends to the "tail length" and tie a constrictor around both legs.
4) tie your button knot, and carefully tighten it down while keeping the tails the same length.
5) pre-tension the knot and remove the constrictor.
6) for shorter soft shackles, trim the tail length down to about 24 diameters.
7) taper 1/2 of the strands starting about 16 diameters from the ends (leave about 8 diameters for the final taper)
8) carefully run the tails into the legs and exit far enough down that you can complete the bury
9) taper the remaining 6 strands of the tails over 8 diameters and milk the legs down to complete the bury
10) slowly pre tension the completed shackle to your working load limit.

I've found that the following tail lengths give me sufficient length to tie the button knot without leaving excess tail to cut off (tail bury minimum 24 diameters):
1/8" - 9" tail
5/23" - 10" tail
3/16" - 12" tail
1/4" - 15" tail

Example: for a 1/8" x 6" soft shackle you would need: (6 + 9) * 2 = 30"

Note: you'll want to practice tying the button knot with longer lines before attempting it with these shorter tail lengths.

Based on NER's MBS numbers for Endura 12 and Estar's pull testing, these shackles would have the following theoretical breaking strengths:
1/8" - 6,440 lbs
5/32" - 9,890 lbs
3/16" - 14,030 lbs
1/4" - 22,310 lbs

I use a 6:1 safety factor for my WLL in my slackline rig, but am fine with a 3:1 or 4:1 on the boat.

Shackles made from Amsteel would have slightly lower theoretical breaking strengths, as Samson's MBS numbers are lower.

#1619 allen

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Posted 23 August 2014 - 05:52 PM

^^ Sterling said they had never seen a line shred like that.  They suggested a different one of their ropes, Marathon, and also suggested using single rope instead of half rope.  I had picked half rope as it would give me almost twice the stretch for a given impact load.  

 

Half rope has 31% stretch for 110kg shock load

Full or single rope has 36% stretch for 220kg shock load

 

Harken had nothing to add.  Thinks the cam cleats are pretty easy on the line.

 

Sterling might be sending me a sample.  He offered 10 meters and I need 12 so we will see.

 

I need to check that the teflon tape didn't come off.  That would be an easy explanation.  Especially given your 10 year use without issue.  I will check Saturday.

 

Allen

 

I have the Sterling rope samples and will try and run some tests today.  He sent two static lines and one dynamic.  I was using half rope so I think it unlikely I will use the full rope he sent as I want the added stretch of the half rope.  I had told them that I was not interested in static line but he asked that I try them.  I don't think he understood that actually using them and finding they unacceptable means my boom broke.  

 

I noticed that the cam cleats I have are not Harken but rather Ronstan.  Does anyone know if Ronstan cam cleats are harder on line than Harken.  I could change them but would only want to if it would help.

 

The numbers for the rope I have been using is 33% stretch for 6.1kN drop.  The full rope is 30% stretch for 8.7kN drop.  The half rope has about 60% more shock protection.  It doesn't have too much static stretch for my application so if I can solve the abrasion issue, I would be happy with it.

 

Allen



#1620 Essington

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Posted 24 August 2014 - 08:37 AM

I noticed that the cam cleats I have are not Harken but rather Ronstan.  Does anyone know if Ronstan cam cleats are harder on line than Harken.  I could change them but would only want to if it would help.


I have replaced older ronstan cam cleats for just that reason, they weren't as smooth (in operation) as harken, and seemed harder on the lines. But, recently ronstan has changed the design of their cams, and they now seem at least as good as harken at about half the price.

#1621 allen

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Posted 24 August 2014 - 01:59 PM

I noticed that the cam cleats I have are not Harken but rather Ronstan.  Does anyone know if Ronstan cam cleats are harder on line than Harken.  I could change them but would only want to if it would help.


I have replaced older ronstan cam cleats for just that reason, they weren't as smooth (in operation) as harken, and seemed harder on the lines. But, recently ronstan has changed the design of their cams, and they now seem at least as good as harken at about half the price.

How long ago was the design of the ronstan cams changed?  Mine are probably 5 years old.  Perhaps I should just change them out to be sure...



#1622 Chacal

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Posted 24 August 2014 - 02:13 PM

Just went through the whole thread.. Whoah! Nice work guys!

 

While reading, I bumped into this topic by allen, but it seemed to have gotten buried under all other stuff.

 

Semi new topic. A Brummel eye splice can be made using just one end with the McDonald Brummel. There is another method that is not "correct" that is a lot easier. Take the working and and pass it through the standing end. That makes a loop. Make a hole in the working end and away from the loop. Pass the loop through that hole. Pull it out. That will look like a Brummel but some of the fibers are twisted. Now bury the working and and taper normally. Is it as strong? Does it matter that the fibers are twisted?

Allen

 

As this technique of making an eye splice without "fixing" the brummel is quite often referred in Google results (e.g. http://www.cofc.co.n...cing-manual.pdf), it would be really nice to know how this compares strength wise to the "correct" one shown e.g. at Allen's site: http://l-36.com/brummel2.php

 

Has anyone done any tests on this?



#1623 thinwater

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Posted 24 August 2014 - 02:57 PM

^^ interesting. Thanks. I wonder if this is one area where things get worse with scale. . . . More heat at a thin surface boundary and more rope mass insulating that heat from dissipating?...

 

I did a few calculations regarding sea anchor lines (nylon) and it seemed probable that somewhere around 5/8"working heat becomes very important. But there are MANY variables. Dyneema works less but is more temperature sensitive. And then there is the whole matter of core/cover slipage around a drum.

 

http://sail-delmarva...-melt-myth.html

 

I think it is clear that anytime you are woking at high load factors things can fall apart. You are challenging the structure and heat is  part of that.



#1624 haligonian winterr

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Posted 24 August 2014 - 02:57 PM

No load tests, but Allen's is my standard eye splice and I've yet to have one fail during normal use. From the people I've talked to and the info I've read; they even caution against twisting the bury inside the outer, to retain full strength. From that, I'd be hesitant to have that much twist in such a high load area.

 

I'm building a breaking bench in a few months, so I can start breaking things at (very) approximate loads.

 

HW

 

Just went through the whole thread.. Whoah! Nice work guys!

 

While reading, I bumped into this topic by allen, but it seemed to have gotten buried under all other stuff.

 

Semi new topic. A Brummel eye splice can be made using just one end with the McDonald Brummel. There is another method that is not "correct" that is a lot easier. Take the working and and pass it through the standing end. That makes a loop. Make a hole in the working end and away from the loop. Pass the loop through that hole. Pull it out. That will look like a Brummel but some of the fibers are twisted. Now bury the working and and taper normally. Is it as strong? Does it matter that the fibers are twisted?

Allen

 

As this technique of making an eye splice without "fixing" the brummel is quite often referred in Google results (e.g. http://www.cofc.co.n...cing-manual.pdf), it would be really nice to know how this compares strength wise to the "correct" one shown e.g. at Allen's site: http://l-36.com/brummel2.php

 

Has anyone done any tests on this?



#1625 thinwater

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Posted 24 August 2014 - 03:17 PM

Dynamic Travellers

 

I've been using 8mm line for ~ 1 year and have zero wear. I could be more careful in my jibes, I certainly sail in a less windy area. But I do have a few thoughts.

 

  • Climbing rope sheaths are generally very tight but thin. They are tight to reduce snagging on rock crysals, but this results in very difficult splicing. The cover is thin (most sailing ropes are 50% core while climbing ropes are 80% core) to maximize the core, where the energy absorption happens.
  • UV. Climbing ropes are not very UV tolerant because they are not outside that much. A climbing rope is not expected to see more than ~ 500-1000 hours of sun before retirement (2-3 months). I suspect your cover may have been in very weak shape when you got it. Climbing ropes generally do not show their real state of wear in the same way as sailing ropes, because they are babied. My rope is an ice climbing line and saw very little UV or pysical wear.
  • Buying only what you need. MEC sells both single and double rope by the foot.
  • Size. In my mind, regardless of the size of the boat, the traveller line should see similar loads so long as the line is hand-tensioned (tackel and boom possition make up the difference). But there is certainly some variation. How hard do you have to pull on the traveller line when hard on the wind, full load? for me that would be ~40-50 pounds.
  • Catamaran. My traveler is long, thus there is more line in the system to tak the jolts. Also, though my rigging is similar, the cleats are located several blocks and 20 feet of line further away.

You might try nylon dockline as a more abration and UV resistant compromize; the stretch will be less, but still far more than polyester or Dyneema. Climbing rope is really not optomized for this purpose, not for all boats. I've sceen acsenders (similar to cam cleats) do that sort of damage to climbing ropes (old rope, falling on ascender).

 This is not unheard of. You have given the rope the worst case abuse:

  • old rope. With a thin sheath and all-over external wear, we have shown that single braid is much weaker than it looks. The cover was toast before you started.
  • short rigging
  • hard jibes
  • possibly sharp cam cleats

The energy has to go somewhere, and flying jibes pack a lot of energy.



#1626 Essington

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Posted 28 August 2014 - 02:45 PM

Estar, Throughout your pull testing, have you tested Dyneema grommets (spliced loops)?

 

Brion Toss describes 2 styles in his Working Rope book, one with a 72 diameter bury and an "overlapping" style where the grommet's circumference is too small to complete full 72 diameter buries.

 

I would guess the style with full the 72 diameter bury to approach 200% of line strength as the load is shared between 2 legs with a locking brummel splice that should approach 100% efficiency.

 

However the overlapping style must be somewhat less efficient due to the shorter bury.

 

If dyneema grommets aren't something you have tested, but would like to, I could throw some together for testing when you return from your sailing adventures.



#1627 Essington

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Posted 28 August 2014 - 02:50 PM

How long ago was the design of the ronstan cams changed?  Mine are probably 5 years old.  Perhaps I should just change them out to be sure...

 

If the cams can be easily mistaken for harken, then they are the new design. If they are silver and sharp as hell, then they are the old design.



#1628 allen

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Posted 28 August 2014 - 02:59 PM

Dynamic Travellers

 

I've been using 8mm line for ~ 1 year and have zero wear. I could be more careful in my jibes, I certainly sail in a less windy area. But I do have a few thoughts.

 

  • Climbing rope sheaths are generally very tight but thin. They are tight to reduce snagging on rock crysals, but this results in very difficult splicing. The cover is thin (most sailing ropes are 50% core while climbing ropes are 80% core) to maximize the core, where the energy absorption happens.
  • UV. Climbing ropes are not very UV tolerant because they are not outside that much. A climbing rope is not expected to see more than ~ 500-1000 hours of sun before retirement (2-3 months). I suspect your cover may have been in very weak shape when you got it. Climbing ropes generally do not show their real state of wear in the same way as sailing ropes, because they are babied. My rope is an ice climbing line and saw very little UV or pysical wear.
  • Buying only what you need. MEC sells both single and double rope by the foot.
  • Size. In my mind, regardless of the size of the boat, the traveller line should see similar loads so long as the line is hand-tensioned (tackel and boom possition make up the difference). But there is certainly some variation. How hard do you have to pull on the traveller line when hard on the wind, full load? for me that would be ~40-50 pounds.
  • Catamaran. My traveler is long, thus there is more line in the system to tak the jolts. Also, though my rigging is similar, the cleats are located several blocks and 20 feet of line further away.

You might try nylon dockline as a more abration and UV resistant compromize; the stretch will be less, but still far more than polyester or Dyneema. Climbing rope is really not optomized for this purpose, not for all boats. I've sceen acsenders (similar to cam cleats) do that sort of damage to climbing ropes (old rope, falling on ascender).

 This is not unheard of. You have given the rope the worst case abuse:

  • old rope. With a thin sheath and all-over external wear, we have shown that single braid is much weaker than it looks. The cover was toast before you started.
  • short rigging
  • hard jibes
  • possibly sharp cam cleats

The energy has to go somewhere, and flying jibes pack a lot of energy.

The rope I used was new at the beginning of the season.  Estar said he has used climbing rope on his traveler for a decade.  Was it exposed to UV?  Mine sure was.  I will remove so it doesn't sit there through the winter.  I am also replacing the Ronstan cam cleats with Harken.

 

Allen



#1629 thinwater

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Posted 28 August 2014 - 08:01 PM

It could well be the cleats. I recall some of those ate rope. You should get at least a few seasons.

I also mark the line so I always have a few inches cushion for the jibe.

#1630 allen

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Posted 29 August 2014 - 01:27 AM

I removed the traveler control line today and installed a short section to keep things in place. It is 1:1 now instead of its normal 5:1.  I had that short section left over from the same line I jsed for the two 5:1 lines.  I had installed the new 5:1 piece three weeks ago after the initial one shredded.  Today I noticed that the color was significantly faded from the 3 weeks in the sun.  I am suspicious of UV damage as being the cause.



#1631 Estar

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Posted 29 August 2014 - 01:41 AM

Estar, Throughout your pull testing, have you tested Dyneema grommets (spliced loops)?

 

.

I did not test grommets, but I did test a lot of different splice lengths and the splice strength does not change a lot even down to quite a short splice (28 diameters).  You loose some few percent because the taper becomes more abrupt.  You might also loose some ability to hold in load load cyclic situations but you can fix that with either some stitching or a Brummel.

 

So if you want to send me some,I would be happy to test some grommets, but I would not expect to see a big difference between the two variants you mention.  I am not pull testing right now, but may be in about a month or so.  

 

The rope I used was new at the beginning of the season.  Estar said he has used climbing rope on his traveler for a decade.  Was it exposed to UV?  M

Yes, my trav line is full time in the elements . . . .but I had been spending a lot of time in cold wet foggy areas so the UV intensity may not have been so high. I have a long piece in my sail locker that has been 'protected' and its color and feel is not much different than the piece that's been outside.



#1632 allen

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Posted 29 August 2014 - 01:55 AM

The rope I used was new at the beginning of the season.  Estar said he has used climbing rope on his traveler for a decade.  Was it exposed to UV?  M

Yes, my trav line is full time in the elements . . . .but I had been spending a lot of time in cold wet foggy areas so the UV intensity may not have been so high. I have a long piece in my sail locker that has been 'protected' and its color and feel is not much different than the piece that's been outside.

Do you know the brand and model of the rope you used?  Mine has faded a lot in three weeks.  I probably need a different model.



#1633 Estar

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Posted 29 August 2014 - 11:46 AM

Unfortunately no - I will post a photo when I am next down on the boat (she is hauled right now for a prop rebuild) and see if anyone can identify it . . . But I do know it is 10mm ish - bigger than what you tried .

#1634 allen

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Posted 29 August 2014 - 09:30 PM

Here is a picture of three samples, each twice.  The failed one is the one with 26 weeks indicated.  But notice that even 3 weeks shows quite some fading compared with the one that has only 1 day shown as 90 weeks.

IMG_20140829_103955.jpg



#1635 bruno

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Posted 31 August 2014 - 04:21 PM

I would be very interested to learn more about rigging standing with NER sts-hsr and max 90, neither seem readily available but potentially cheaper and stronger than dux, any product outreach?

#1636 thinwater

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Posted 31 August 2014 - 10:41 PM

 

The rope I used was new at the beginning of the season.  Estar said he has used climbing rope on his traveler for a decade.  Was it exposed to UV?  M

Yes, my trav line is full time in the elements . . . .but I had been spending a lot of time in cold wet foggy areas so the UV intensity may not have been so high. I have a long piece in my sail locker that has been 'protected' and its color and feel is not much different than the piece that's been outside.

Do you know the brand and model of the rope you used?  Mine has faded a lot in three weeks.  I probably need a different model.

 

Mamut Genesis 8.5mm. Not sayin' that your don't need a larger size (they make others). But it has been in the sun 2 years and is pristine with minimal fading.

 

Gym rope is sold by the foot, is burly for daily use, and has more cover, as shck absorption is less important than traditional climbing.



#1637 Zonker

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Posted Yesterday, 11:32 AM

We also use climbing rope for an anchor snubber on our catamaran. It's a bridle that is always in the sun (tied to the bows).  After about 5 years (2-1/2 in Brisbane, Australia with probably highish UV) I'm going to replace it. It's seen some very high loads but the cover is still in good shape.  I also used climbing rope for dock lines and it held up pretty well but abrasion of the cover was the weak spot as well.



#1638 Estar

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Posted Yesterday, 05:31 PM

Question: when you all use soft shackles, can/do you operate them single handed or do you need two hands? Are some of the designs easier to use single handed than others?

The question has come up related to both anchor snubbers and halyard shackles use - that design for easiest single handed operation would be useful.

#1639 allen

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Posted Yesterday, 05:37 PM

I have a design I call a double soft shackle that was designed for single hand attachment. It has less strengh but more than half if you use larger line for the knot. I used for a bit to attach a line to the clew of a flying sail. Removing it would take two hands.

#1640 JumpingJax

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Posted Yesterday, 07:13 PM

Question: when you all use soft shackles, can/do you operate them single handed or do you need two hands? Are some of the designs easier to use single handed than others?

The question has come up related to both anchor snubbers and halyard shackles use - that design for easiest single handed operation would be useful.

 

We run our long snubbers through the bow roller and back on deck to attach them to the chain so we don't need to avoid two handed attachment.  We've tried playing with single hand use, and sometimes can succeed, but it's a slower and less reliable process so we don't rely on it. 

 

If we tried opening the loop before threading through the link of anchor chain, it was hard to feed through accurately and quickly.  When we fed through and then tried opening the loop with one hand, it was awkward and slow.  In either case, feeding the stopper through the loop with one hand was often the worst part, with the shackle too floppy to make the effort simple and direct.  It generally could be done, but took far too long to get the knot through and get a good closure. 

 

For forward halyards, too, we make sure of a stable position on deck, use two hands for the shackle and move on.  With roller furling headsails, we're not doing a lot of sail changes and rarely find two handed use a difficulty. 

 

We could really appreciate a good one-handed technique for our main halyard.  Our gooseneck is so high, and our luff slide stack so much more, that attaching the main halyard to the headboard is often our "Everest of the day."  (Sorry, I was reading that other thread last night, and I tried to resist, but I couldn't help myself.)  It's either a climb on the winches or a bos'ns chair (for m'Lady) however the halyard is attached.  And whatever shackle we use, it demands two hands. 



#1641 allen

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Posted Yesterday, 07:53 PM

We could really appreciate a good one-handed technique for our main halyard.  Our gooseneck is so high, and our luff slide stack so much more, that attaching the main halyard to the headboard is often our "Everest of the day."  (Sorry, I was reading that other thread last night, and I tried to resist, but I couldn't help myself.)  It's either a climb on the winches or a bos'ns chair (for m'Lady) however the halyard is attached.  And whatever shackle we use, it demands two hands. 

Secure a stopper knot to the headboard and use a line shackle on the halyard.  This assumes you have Amsteel or equivalent in the halyard.  Pretend the ring is your headboard:

shackle_and_stopper_2.jpg



#1642 JumpingJax

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Posted Today, 03:08 AM

Nice, Allen.  I'll try that one.  Won't eliminate the climb, but looks like a good, quick attachment. 



#1643 Merit 25

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Posted Today, 07:05 PM

I'm rigging an i550 with NER sts-hsr now.  I'm also a NER dealer, what additional information are you looking for?  And readily available is 3 weeks away for just about anything they carry. And yes, it is cheaper and stronger than dux. Let me know if I can help.

 

I would be very interested to learn more about rigging standing with NER sts-hsr and max 90, neither seem readily available but potentially cheaper and stronger than dux, any product outreach?

 






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