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Rope/knot/splice load testing


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#1501 Zonker

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Posted 09 May 2014 - 06:15 AM

I'm not a fan of soft handholds.  Sometimes the boat lurches the other way and the soft handhold does nothing to stop you moving in that direction and banging your knuckles.  They are OK if you are an ape and are happy swinging back and forth.



#1502 pelorus32

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Posted 09 May 2014 - 07:37 AM

This should be a larger version of the picture in question.

13430193923_1a3bb334d7_b.jpg

  • The sail has an attached loop at the clew
  • That loop has two yellow, endless loops
  • Each sheet has a green/blue soft shackle with a carbon dog bone which goes through one of the yellow lows on the sail
  • Each sheet has a spliced eye with over braid.

Can't tell anything else ;)

 

Now on to the really interesting thing...those boots :-)



#1503 allen

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Posted 09 May 2014 - 06:52 PM

A friend from Google+ when down to the SCA boat and took a look for me.  He said it looked just like the one in the photo below, which is RigPro. 

 

Here is what he said:

 

"I just had a look at the boat. All the "shackles", halyards & sheets are nothing more than loops and a dogbone. The loops are made by the rigger and the dogbones are both SS and alum. There's a little wrap of Velcro keeping it all together. All very simple....  It's like the RigPro. But I'm not entirely sure it's RigPro's work as any rigger can make them."

 

Allen

 

 

dogbone1-1024x768.jpg



#1504 Estar

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Posted 09 May 2014 - 07:23 PM

Ah, so the photo must have caught her just as she was inserting the dogbone thru the other loop. Thanks.

What are the advantages/disadvantages of the metal dogbone vs soft shackles? I have made/broken a couple (very strong) but have never used them on the boat.

#1505 thinwater

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Posted 09 May 2014 - 07:36 PM

The biggest problem with softshackles, in my personal opinion, is that doing what she is doing can be trouble in difficult conditions. It can be hard to the get the eye to stay open when things are bouncing about. Fixed eye shackles, including those with dogbones, are less fiddly. Even though the Velcro adds a step, I bet it is more practical for the racer.

 

What is the line construction? Notice how it has flattened out under no load, like the cover-only shackles I use. I like that character because it gives them a more positive bite, but I don't know if that is their reasoning.

 

I'm willing to bet that for smaller sizes the SS core is not needed, though it is a simple matter. Since 1/2" Al would do for many boats, they could be easily turned on any drill press.

 

But now we have added a bit on metal flogging around with the clew. I think I'll stick with all-line shackles.

 

---

 

My challenge is switching sheets underway, since i use inner and outer sheets (shrouds in the way). I'm thinking of adding a loop for one pair, since the eye gets rather crowded. It would also make getting that critical bit of slack easier, since the loop is unloaded.



#1506 Christian

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Posted 09 May 2014 - 08:52 PM

Ah, so the photo must have caught her just as she was inserting the dogbone thru the other loop. Thanks.

What are the advantages/disadvantages of the metal dogbone vs soft shackles? I have made/broken a couple (very strong) but have never used them on the boat.

The advantages of dogbones are ease of attaching/detaching and breaking strength - and if you have a stack of dogbones and loops - much faster to put together



#1507 Christian

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Posted 09 May 2014 - 08:54 PM

Ah, so the photo must have caught her just as she was inserting the dogbone thru the other loop. Thanks.

What are the advantages/disadvantages of the metal dogbone vs soft shackles? I have made/broken a couple (very strong) but have never used them on the boat.

The advantages of dogbones are ease of attaching/detaching and breaking strength - and if you have a stack of dogbones and loops - much faster to put together

BTW - climbing strops and dogbones make excellent loop shackles - if used in an application with potential flogging you just add a bit of tape or double-sided velcro



#1508 pelorus32

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Posted 09 May 2014 - 11:42 PM

[snip]

What is the line construction? Notice how it has flattened out under no load, like the cover-only shackles I use. I like that character because it gives them a more positive bite, but I don't know if that is their reasoning.

 

[snip]

 

But now we have added a bit on metal flogging around with the clew. I think I'll stick with all-line shackles.

 

---

 

My challenge is switching sheets underway, since i use inner and outer sheets (shrouds in the way). I'm thinking of adding a loop for one pair, since the eye gets rather crowded. It would also make getting that critical bit of slack easier, since the loop is unloaded.

 

I'm fairly certain that the "line" is in fact a multi-strand Dyneema "loop". You take a piece of chafe sleeve, and make a series of Dyneema loops which punch through the wall of the chafe sleeve at key places. It's finished by feeding the chafe sleeve around the "eyes" and burying the "end tags" of the chafe sleeve back into the body.

 

My thoughts entirely on why you wouldn't use a dog bone. I've worked really hard to get rid of hardware which damages wooden spars. I don't want to put it back again!!



#1509 allen

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Posted 10 May 2014 - 01:52 AM

I looked at the strength and diameter of this stuff and do not see a strength advantage although it is difficult to compare without holding one in my hand.



#1510 Merit Therapy

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Posted 11 May 2014 - 02:08 AM

This is such a great thread; thanks! I've skimmed every post and also read through http://www.bethandevans.com/load.htm but I didn't notice any break test of the tenex to amsteel splice described as splice 2 of http://l-36.com/halyard_splice.php I'm looking for a double-check of my intuition on the strength of this splice. My expectation is that worst case the splice will derate the amsteel by 80% because the six strands of tenex jammed in to would be similarly bad to an amsteel tail sticking out of a bury? I'm thinking of replacing a reefing line with such a spliced line. Even derating by 80% it should have a >10 factor of safety for the expected loads on my 25' sloop. I would consider downsizing to 5/32nds but I already have a supply of 3/16ths.

#1511 allen

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Posted 11 May 2014 - 02:29 AM

^^ The link you gave it to my StaSet to Amsteel splice which has been discussed in this thread and several people are using it.  The Tenex to Amsteel splice is variation #2 on this page:

http://L-36.com/halyard.php



#1512 Merit Therapy

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Posted 11 May 2014 - 02:47 AM

Oops, yeah good catch, I had both tabs open. I meant the http://L-36.com/halyard.php Tenex to Amsteel one.

#1513 Merit Therapy

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Posted 11 May 2014 - 04:39 AM

After making the splice I can see why it might be 100% of line strength. The line is doubled at the part where the amsteel is weakened by having the six strands of tenex enter. Though since the lines stretch differently the section with doubled line is likely not the sum of the two lines strength.

#1514 allen

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Posted 11 May 2014 - 05:12 AM

^^ The real unknown on this splice is how it reacts at high loads given the differential stretch.   The StaSet to Amsteel tends to get hernias.  They don't seem to hurt the strength but there the Amsteel is so much stronger than the StaSet that it is a different story.  Here the Tenex and the Amsteel are very similar in strength.  I have used this splice but never at high loads.  I used it for a tack line on a jib that we kind of used in a unique way.



#1515 scaredsheep

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Posted 12 May 2014 - 03:41 PM

thanks for all this sorry I haven't read most of it

I have to splice eyes in 12 strand dyneema
9/16ths
I would rather not use a brummell splice

tuck splice appropriate with stitching?

taper 72 diameters ?

thank ewe

#1516 allen

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Posted 12 May 2014 - 03:55 PM

^^ that is fine.  Use thick stitching line, about the same diameter as one of the strands of the rope.  Link



#1517 rule69

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Posted 12 May 2014 - 06:13 PM

^^^

 

 

I've taken to using my bent wire splicing tool for this stitching rather than a sail needle.



#1518 pelorus32

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Posted 12 May 2014 - 09:17 PM

^^^

 

 

I've taken to using my bent wire splicing tool for this stitching rather than a sail needle.

 

My recent discovery - thanks to my bike mechanic son - 1mm bicycle spokes are quite happy to be bent tightly in half. They make excellent splicing wands for small stuff like 2.5mm Dynex. I just wrap some 1.7mm Dynex around the two ends - one of which has the bit that connects to the hub. It forms a workable handle. The best thing is they are cheap.



#1519 rule69

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Posted 12 May 2014 - 09:35 PM

^^^

 

Cool. FWIW, I'm using 0.041" annealed SS locking wire. Works for me and I keep it in my tool kit anyway. I don't seem to need a handle for single braid splicing but I sometimes bend the back end over so it doesn't slip into the line.



#1520 Alex W

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Posted 12 May 2014 - 10:05 PM

Standard bicycle spokes are 1.8mm or 2.0mm.  Are the 1mm spokes that you are using flattened aero spokes?

 

I use old spokes with a bullet nose as a fid on small dyneema (like Lash-It), but I tape the line to the fid so there is no bending involved.

 

You can also get piano wire in almost any size that you'd want at most Ace Hardware stores cheaply.



#1521 pelorus32

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Posted 13 May 2014 - 02:39 AM

Standard bicycle spokes are 1.8mm or 2.0mm.  Are the 1mm spokes that you are using flattened aero spokes?
 
I use old spokes with a bullet nose as a fid on small dyneema (like Lash-It), but I tape the line to the fid so there is no bending involved.
 
You can also get piano wire in almost any size that you'd want at most Ace Hardware stores cheaply.


Oops they are apparently 1.5mm and no they're not flattened aero.

Thanks for the Ace Hardware tip but I don't think they made it down under ;)

#1522 Robc

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Posted 13 May 2014 - 05:48 AM

With regards to dogbone loops,
You do gain strength as there is no knot to reduce strength, you end up with a much stronger set up, as long as the dogbone can take it.


Two other reasons to use them, apart from ease if use with cold hands;
They are much more slimline when you start using bigger diameter rope. A button knot can be a great thing to catch halyards on when prepping for a spin hoist for example.

Also when it has been heavily loaded, a big button knot hitting you in the head hurts just as much as a carbon dogbone in my experience

Just my 2 cents

#1523 scaredsheep

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Posted 14 May 2014 - 10:25 AM

thank ewe Alllen

Butt the strands aré 1/4 inch. perhaps six strands of
hvy waxed handsewing thread?

#1524 allen

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Posted 14 May 2014 - 01:18 PM

thank ewe Alllen

Butt the strands aré 1/4 inch. perhaps six strands of
hvy waxed handsewing thread?

I see from their video that they didn't follow that recommendation themselves.  Just get some of the thick stuff at the marine store.



#1525 Brion Toss

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Posted 19 May 2014 - 01:39 AM

Robc, on 12 May 2014 - 22:55, said:
With regards to dogbone loops,
You do gain strength as there is no knot to reduce strength, you end up with a much stronger set up, as long as the dogbone can take it.

Strength numbers for these aren't all that impressive, actually. For instance, a Harken Loupe, 10mm, has a working load of 5,645lbs. Much weaker than what we've seen in tests here, assuming a 2:1 safety factor. Granted, that 10mm includes the cover, but then you have to have the cover -- and the dogbone -- to make the thing work.

Quote
Two other reasons to use them, apart from ease if use with cold hands;
They are much more slimline when you start using bigger diameter rope. A button knot can be a great thing to catch halyards on when prepping for a spin hoist for example.

We have differing experiences here. At least the self-closing shackles seem as easy as dogbones, cold hands or no. And it might be that oversize shackles will be more likely to snag things...

Quote
Also when it has been heavily loaded, a big button knot hitting you in the head hurts just as much as a carbon dogbone in my experience

Actually, anything can have a damaging or fatal impact if it hits you at sufficient speed. Limbs and necks have been broken by flogging ropes, and we usually think of that as soft. The difference with a soft shackle is how unlikely it is to cause damage if it hits you at relatively low speeds (which are more typical, I think).

#1526 Robc

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Posted 20 May 2014 - 07:23 AM

Brion, that Mwl isn't for a set up with a dogbone?

I was suggesting a 10mm loop in dogbone setup is stronger than the same diameter rope made into a soft shackle.
Obviously both in basket but the soft shackle breaks at the knot well before the loop would break on the dogbone?

Mentioned the cold hands from someone's earlier post, but I'd really suggest the slimline point is of more concern to me,
I'm a big fan of soft shackles and hardly use dog bones which have their own issues! A well made soft shackle is great! But large, (14mm+) diameter soft shackles, the knots do tend to catch halyards pretty easily.

Just suggesting, when making soft connections for higher load applications, a dogbone may be a better way to achieve the higher break loads without ending up with a massive button knot...


I agree a soft shackle is less likely to hurt at low speed.m a large button knot once it's been loaded just becomes like a piece of rock though...

#1527 allen

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Posted 20 May 2014 - 02:57 PM

 But large, (14mm+) diameter soft shackles, the knots do tend to catch halyards pretty easily.

 

I have not tried using line that large but here is how I keep my soft shackles from hanging up on the rigging.

soft_shackles_vel.jpg

 

And when Brion mentioned a self closing soft shackle I assume he was talking about my better soft shackle.  Self closing is really a lot of the "better".  http://L-36.com/soft_shackle_9.php  The one in the picture above is the old style, although you can't really tell from the picture.

 

Brion's point on strength is that 14mm Amsteel is stronger than the 14mm line that a dogbone would be made of because the dogbone line gets its strength from the core which is less than the overall diameter because of the cover.  When I looked at the strength I also found them about the same for a given size line.  I don't recall what assumptions I had to make if any to reach that conclusion tough.

 

Allen

L-36.com



#1528 JumpingJax

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Posted 20 May 2014 - 03:16 PM

Brion, that Mwl isn't for a set up with a dogbone?

I was suggesting a 10mm loop in dogbone setup is stronger than the same diameter rope made into a soft shackle.
Obviously both in basket but the soft shackle breaks at the knot well before the loop would break on the dogbone?

Mentioned the cold hands from someone's earlier post, but I'd really suggest the slimline point is of more concern to me,
I'm a big fan of soft shackles and hardly use dog bones which have their own issues! A well made soft shackle is great! But large, (14mm+) diameter soft shackles, the knots do tend to catch halyards pretty easily.

Just suggesting, when making soft connections for higher load applications, a dogbone may be a better way to achieve the higher break loads without ending up with a massive button knot...


I agree a soft shackle is less likely to hurt at low speed.m a large button knot once it's been loaded just becomes like a piece of rock though...

 

A 14mm Amsteel soft shackle will have a breaking strength of ~68,000 lb. if I understand correctly what these guys have achieved.  At 30%, that yields a SWL of ~20,000 lb.  What the hell are you rigging with that size load?  Or did you miss the fact that the best of the work done produces a (properly made and loaded) soft shackle with a breaking strength of ~200% of line strength?  That makes a 14 mm Amsteel soft shackle suitable for a sheet much larger than 14 mm; try 22 mm or even 24 mm for an equivalent safe working load as the soft shackle.  Not very many of us are using sheets that stout. 



#1529 Robc

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Posted 20 May 2014 - 09:13 PM

Allen, I like your idea there, I've tried making the knot sit in the inside of the loop rather than outside, but haven't tried loading it like that, we use webbing clews though so don't think I could sit the knot like that.

We actually use soft shackles, rather than dogbones, but have been looking into this quite extensively for that reason.

Sorry I do appear to have missed your works showing you achieved 200% of line strength with a soft shackle! I've not seen that anywhere else before and had always believed you were hitting about 100% of line strength when you factor in the loss from the knot.

Apologies if I'm wrong here, can you point me to where you discovered this ?


Allen, I was going on the basis of two loops of the same construction, say for arguments sake, 10mm line, one is a continuous loop (with correct buries) joined with a dogbone, one is made into a soft shackle arrangement.
In this case, both are technically in basket, so you get 200% line strength but you lose more from the knot which is where a soft shackle always breaks, rather than a dog one set up with no knot...

I may well be wrong in this, would love to discuss further...


Jumping jax, your calcs are correct and we do, but my point was more than when you get to highly loaded, bigger lines, you may find slight advantages in dogbones, hence the use on Volvo boats, larger boats, etc.

#1530 allen

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Posted 20 May 2014 - 11:49 PM

The strength numbers come from the testing estar did in this thread. I have always said more than line strength. I think his test came in at 170% of line strength. I still say more than line strength :-)

The strength numbers come from the testing estar did in this thread. I have always said more than line strength. I think his test came in at 170% of line strength. I still say more than line strength :-)

#1531 Estar

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Posted 21 May 2014 - 12:57 AM

Standard soft shackles = "about 160%", the test range is 130-180%
Stronger soft shackle design = "about 240%", test range 210 - 250% (the weaker ones in that range had obvious construction deficiencies)

I have not tested loops with dogbones, but I presume they break at the dogbone bend radius. So their breaking strength will depend on the diameter of the bone vs the diameter of the line. Can anyone tell me what that typical D/d is for a dogbone? If we have that we can calculate their strength pretty accurately.

#1532 Robc

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Posted 22 May 2014 - 07:43 AM

I don't have a typical but will try and find out. You couldn't point out the page in this forum where you posted those numbers before?

#1533 Robc

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Posted 22 May 2014 - 07:52 AM

Just reading through your own site Estar. Good stuff

#1534 JumpingJax

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Posted 22 May 2014 - 05:59 PM

I don't have a typical but will try and find out. You couldn't point out the page in this forum where you posted those numbers before?

 

If you haven't read through the whole thread, you've missed a LOT of great ideas and useful information.  It's worth your time.  And polite, too. 



#1535 Reht

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Posted 22 May 2014 - 07:09 PM

I don't have a typical but will try and find out. You couldn't point out the page in this forum where you posted those numbers before?

 

If you haven't read through the whole thread, you've missed a LOT of great ideas and useful information.  It's worth your time.  And polite, too. 

To be fair it is an impressive read. Many of the major contributors have summarized the most important things on their personal sites (check their signatures). Robc, take the time, read a page or two every day and you'll be through it in no time and may even want to go back to review different parts as the subject matter has changed with time.

 

If (when?) somebody has a lot of time on their hands to write a complete report on all the findings I'm sure it'll be a fun read.



#1536 Estar

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Posted 22 May 2014 - 08:52 PM

Btw . . . I am now on my boat, slowly cruising my way north for the summer (in block island waiting out some easterlies right now). I will have internet thru Nova Scotia, but then loose everything except text email.

I have had a couple people ask if I will break things, and I will be happy to continue doing that in the fall when I get back home. I have a couple ideas and questions I want to test myself. So, keep notes when you have ideas, and let me know in the fall of anything worth testing and breaking.

I hope thinwater will also continue his pendulum chafe testing. There were some very interesting results there.

#1537 rule69

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Posted 22 May 2014 - 11:00 PM

Thanks for the great work Evans.



#1538 Robc

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Posted 23 May 2014 - 06:19 AM

Apologies, I have read a lot of this forum but hadn't come across those break numbers, have found it on the website and will of course keep reading when I get the chance

#1539 Robc

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Posted 23 May 2014 - 06:33 AM

It is possible/easy to replace the diamond knot weak point with a spliced on aluminum toggle (3/8" rod x 2"). This will increase the strength by about 30% vs. the diamond knot, and the soft shackle will then break at the small bend radius where the 'noose' goes around the line just below the toggle.


Estar on your site you mention the above, is that versus the standard soft shackle design but coming out weaker than the improved soft shackle?

#1540 Robc

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Posted 23 May 2014 - 07:03 AM

And what I was trying to get at with dogbones is what Estar has said nicely here....

As expected, the diamond breaks at 46% (of line strength), which is exactly consistent with tested 170-180% soft shackle strength (400% double loop strength x .46 = 184%, with perhaps 10% additional loss in the locking and bury and construction imperfections).


If you remove the diamond knot, you are heading nearer 400% line strength dependant on dogbone strength, and, mainly, bending radius....
Obviously unlikely to achieve 400% but if you gain significantly over a soft shackle surely it's a good reason to use them, minus the bit of metal in the middle.

#1541 Estar

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Posted 23 May 2014 - 09:14 AM

^^ yes, but you need a D/d bigger than 2 to start getting a strength improvement (over the stronger design), and 5 to get a really big bump. I am pretty sure none of the bones are 5 times the line diameter. I don't know, and would be interested to know, if they are typically even 2x line diameter?

#1542 allen

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Posted 23 May 2014 - 01:22 PM

@Robc. Just to emphasize Estar's point.  The diamond knot is the weak point but if you replace the diamond knot with one of the hybrid knots, for example THIS ONE, or the improved soft shackle HERE, the weak point quickly becomes the eye.  If the eye were a 1:1 bend radius, the bend would be about  50% of line strength and the overall shackle would be 4x 50% = 200% of line strength.  The bend radius is a little more than 1:1 so the shackle is a little stronger than 200%.  To get 400%, you would need an infinite bend radius which why Estar is suggesting a 5x bend radius to really make a difference.  Bend radius and strength loss are also discussed in this thread.

 

Allen

L-36.com



#1543 Robc

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Posted 23 May 2014 - 08:00 PM

I agree, and see what you are saying...

Minus bury length this is maybe the other advantage of making the loops out of multiple passes of smaller rope in a covered loop?


Typically I think it's safe to say I've never come across dogbones much more than 1.5 times overall line diameter...
But they have been made as I mention above...

I'd never considered that as part of the reason though

#1544 JumpingJax

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Posted 24 May 2014 - 05:42 AM

Looks like some dog bones will have to be pulled in the fall to validate the superiority of your works. 

 

And I think you guys (three or four) should combine to write and (self) publish a book on this work.  You might make a few dollars, but far more importantly, it would make the work more accessible to the sailing community more broadly than this thread and your individual web sites.  I think it's too much material for a magazine article.  And the collective voice of all of you together could be an important contribution to the perceptions of the work away from the dubious provenance of SA.  (Sad to say, there are quite a few sailors who will never see this thread because it's on SA.  And, even with the notice the thread has gotten all over SA, including the "mythical Front Page," there are a lot of Anarchists who won't take the trouble to digest the whole thread.) 



#1545 Robc

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Posted 24 May 2014 - 10:01 AM

Never claimed superiority just discussing the theory behind it.... But more than willing to break some!
What do we want to test exactly, 1 x dia, 2 x dia and 5 x dia would give a good indication?

#1546 Estar

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Posted 24 May 2014 - 01:16 PM

^^

There are in fact two "bends" to consider in a typical dogbone loop.

One is around the bone. That is pretty easy and streight forward.

But in most bone/loop designs I have seen, when it is closed/loaded, there is also another loop bend around the line itself (just under snugged up against the bone). In strength that is going to be very similar to the noose on a soft shackle, and depending on construction, perhaps weaker than the "stronger soft shackles" with their reinforced tails creating 4 strands for the noose to crunch on.

#1547 haligonian winterr

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Posted 24 May 2014 - 09:07 PM

Put me on pre-order for that!

 

As much as I love the internet, delving through this thread every time I need to find something is a pain. I'd love to have this in a hard copy! Would go right next to the Ashley and the Rigger's Apprentice.

 

HW

 

Looks like some dog bones will have to be pulled in the fall to validate the superiority of your works. 

 

And I think you guys (three or four) should combine to write and (self) publish a book on this work.  You might make a few dollars, but far more importantly, it would make the work more accessible to the sailing community more broadly than this thread and your individual web sites.  I think it's too much material for a magazine article.  And the collective voice of all of you together could be an important contribution to the perceptions of the work away from the dubious provenance of SA.  (Sad to say, there are quite a few sailors who will never see this thread because it's on SA.  And, even with the notice the thread has gotten all over SA, including the "mythical Front Page," there are a lot of Anarchists who won't take the trouble to digest the whole thread.) 



#1548 Reht

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Posted 24 May 2014 - 10:38 PM

Looks like some dog bones will have to be pulled in the fall to validate the superiority of your works. 

 

And I think you guys (three or four) should combine to write and (self) publish a book on this work.  You might make a few dollars, but far more importantly, it would make the work more accessible to the sailing community more broadly than this thread and your individual web sites.  I think it's too much material for a magazine article.  And the collective voice of all of you together could be an important contribution to the perceptions of the work away from the dubious provenance of SA.  (Sad to say, there are quite a few sailors who will never see this thread because it's on SA.  And, even with the notice the thread has gotten all over SA, including the "mythical Front Page," there are a lot of Anarchists who won't take the trouble to digest the whole thread.) 

I support this idea enough that if it were being compiled while I have time, I would be willing to put in time piecing information together from this thread.



#1549 fifo

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Posted 25 May 2014 - 12:15 AM

Page jump

#1550 Ishmael

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Posted 25 May 2014 - 04:12 AM

Page jump

 

Clean that up, right now.



#1551 Robc

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Posted 25 May 2014 - 07:23 AM

Good point Estar regarding bend radius, I guess having mutiple passes of smaller rope helps this again as each strand experiences a Much better bend radius?
But didn't think of that being the main break point!

It'd be hard to match two loops, one loop of larger stuff versus a mutiple pass loop, in order to test this I'd guess? Too many variables involved...

#1552 Estar

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Posted 26 May 2014 - 11:06 PM

^^ to "match" multi-pass little to single-pass big . . . You would need some "efficiency measure" either match BS to $ value of line, or to rated strength.

But, however you look at it, my sense is that the bones had a strength advantage vs the conventional soft shackle design but don't vs the "stronger" designs. The bones may be easier/faster to use - I don't know since I don't have enough experience with them.

For those of you who have used them . . . Is the Velcro essential, on a flogging application like the jib clew? The Velcro obviously adds some operational complexity and probably need to be replaced (once a year?).

#1553 allen

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Posted 28 May 2014 - 07:19 AM

And now for something completely different.  I think it would be informative to test a cleat hitch.  I know of two ways to tie a cleat hitch that I consider "correct."  However, when I see people tie them, I see many ways and I am sure most of you have as well.  The two start the same:

1) Around the far end of the cleat

2) Continue around the base so the line not has gone under each end once

3) Cross over and go round the opposite end

4) Cross over again and go around the first end

 

The difference is at this step.  In one method, the cross over at step 4 is twisted so that you end up with two parallel lines with one line over it.  The second method does not do the twist so the hitch is not locked but instead does one more wrap around the base.  This second method is said to be easier to undo and less subject to jamming.  Good for a high load line that you need to get off such as a cleat holding a jib sheet.

 

Variants I have seen on my boat include not going around the base (step 2), multiple cross overs, and the old locking in the reverse direction on step 4 to that you do not end up with one over two.  Also, step one around the near end instead of the far end.  This is said to jam easily.

 

Is there a difference in strength and jamming between these methods?



#1554 haligonian winterr

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Posted 28 May 2014 - 02:01 PM

This has probably been asked/tested before, but is there any truth to permanent marker (ie Sharpie) ink degrading fibers to the breaking point?

 

I know stores sell specialized "rope markers" but is it really that bad for the fibers/

 

HW



#1555 allen

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Posted 28 May 2014 - 03:20 PM

Why can't I find either of the cleat hitches I described above in Ashley?

 

7571143124_6874892dd6_z.jpg

 

Also, I cannot find a single image of the second variation I described.  The closest I can find is this, which has an extra half turn which I think might cause this to bind up. I don't think this is correct as I think it can bind up with that third half turn under the cleat.

 

big_cleat54296.gif



#1556 Presuming Ed

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Posted 28 May 2014 - 03:53 PM

That last one looks like the OXO method that the RYA teach. Not sure the extent to which an actual standard method is needed - but I suppose it does make it easier when instructing complete novices.

Also unsure how much of a problem the binding up thing is with modern rope. Three strand hemp, yes.

#1557 allen

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Posted 28 May 2014 - 04:02 PM

This comes up on my boat because you need to use the first method to allow for enough space on the cleat to hang the coil the way I want.  I think it is important to have a standard way so that anyone can come up to the coil and drop it on deck and know it will run free.  But trying to accomplish this with experienced sailor is most difficult.  Data would be helpful.



#1558 rule69

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Posted 28 May 2014 - 05:22 PM


Also unsure how much of a problem the binding up thing is with modern rope. Three strand hemp, yes.

 

I think rope type is an interesting point to consider. I noticed that polypro (eg. "Silver line") slips with the usual hitch. It was in use as dock lines, but maybe falling out of favor, when I was in Australia in the early aughts. Folks using it put on a few extra half hitches.



#1559 memopad

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Posted 28 May 2014 - 05:24 PM

I do it in the way your photo shows Allen, the "first" method. That diagram for the second method seems off. Too much rope around the bast of the cleat for my liking, and the wraps around the horns don't tuck under eachother? Am I seeing that correctly? Maybe it's not as important as I think it us, but I can't imagine not doing the tuck on a horn cleat.



#1560 allen

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Posted 28 May 2014 - 05:41 PM

^^ The second method cannot jam and is easy to undo.  There is no lock other than the last turn around the cleat.  My friend, who is a Master Mariner and X-Coast Guard, uses that for his sheets.  He doesn't want to have then jam.  They do not come off but I would not use it for a dock line or halyard.  I use the first method but I also use cam cleats for my sheets so it is not an issue.



#1561 memopad

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Posted 28 May 2014 - 11:36 PM

^^ The second method cannot jam and is easy to undo.  There is no lock other than the last turn around the cleat.  My friend, who is a Master Mariner and X-Coast Guard, uses that for his sheets.  He doesn't want to have then jam.  They do not come off but I would not use it for a dock line or halyard.  I use the first method but I also use cam cleats for my sheets so it is not an issue.

 

I guess I'm only using horn cleats for dock lines and anchor lines. For sheets, sure. I would never walk away from my boat without the lock.



#1562 Estar

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Posted 28 May 2014 - 11:50 PM

I use a tug boat hitch if I don't want it to jam. And/or if I want to be able to release/ease it off under load.

 

But generally, I also only use horn cleats for dock lines (And anchor snubbers) and not for sheets.



#1563 JumpingJax

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Posted 30 May 2014 - 04:20 PM

When sheets are lead to a cleat from a self-tailing winch, as shown in the photo, any load at the cleat is rather slight.  It wouldn't seem too critical what method is used as long as it isn't going to jump off all by itself, Heaven forfend! (and leave the sheet at the mercy of the self-tailer) 

 

A sheet stopper is a bit more trouble to deal with and more prone to slip, so the cleat is - potentially - facing a higher load. 

 

For dock lines, snubbers and maybe a few other cases, the hitch used on the cleat is important enough to warrant testing.  That would seem to indicate that any testing you guys do should give first priority to nylon lines. 



#1564 allen

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Posted 30 May 2014 - 04:43 PM

^^ I had not noticed the winch in the picture was self tailing.  Belt and suspenders.  My winches are manual so the cleat is important.  In my case, they are halyards.  I cleat the halyard, coil the line, and hang it on the cleat.  The cleats are not large enough for people to do the cleat hitch just any which way.

 

The questions of interest are strength and jamming.  There are several methods that are of interest.  There is the 3/4 round then x with and without the lock.  Another round if no lock.  Same but with full turn to begin with.  Then there are what people call the incorrect ways the main one being where the twist lock is backward.  Beyond that there are probably a number of uninteresting incorrect ways.  The other incorrect way of interest is where the initial wrap starts from the near side of the cleat instead of the far side.  This assume a cleat that is installed at an angle.

 

Allen



#1565 Islander Jack

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Posted 30 May 2014 - 06:59 PM

For what it's worth, I always thought that Allen's first method (shown in his photo) was the only acceptable method.

 

A possible addition is to put a bight in the final lock so that uncleating is simply a matter of tugging on the bitter end and unwrapping.  Doesn't work with parallel core, though, because when you tug on the bitter end the bight doesn't close enough to pull easily through the lock.



#1566 rule69

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Posted 30 May 2014 - 07:44 PM

For what it's worth, I always thought that Allen's first method (shown in his photo) was the only acceptable method.

It's the one I was taught half a century ago as "THE ONE TRUE METHOD". I like it. I use it. It is neat, tidy and quick. But, while traveling in a far off land with different traditions, I found it doesn't work well with slippery lines on polished cleats.



#1567 JumpingJax

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Posted 31 May 2014 - 05:17 AM

^^ I had not noticed the winch in the picture was self tailing.  Belt and suspenders.  My winches are manual so the cleat is important.  In my case, they are halyards.  I cleat the halyard, coil the line, and hang it on the cleat.  The cleats are not large enough for people to do the cleat hitch just any which way.

 

The questions of interest are strength and jamming.  There are several methods that are of interest.  There is the 3/4 round then x with and without the lock.  Another round if no lock.  Same but with full turn to begin with.  Then there are what people call the incorrect ways the main one being where the twist lock is backward.  Beyond that there are probably a number of uninteresting incorrect ways.  The other incorrect way of interest is where the initial wrap starts from the near side of the cleat instead of the far side.  This assume a cleat that is installed at an angle.

 

Allen

 

Well, sure, the hitch is far more important if your winches (sheet or halyard) aren't self-tailing.  But even then, the winch still serves (with a proper number of turns of course) to reduce the load on the hitch at the cleat to a modest level, so it's not the "High Test" case.  A dock line goest through a chock and direct to its cleat, and then a thunder storm arrives and hits your beam with 40, 50 knots or even more: that's the test of the hitch. 

 

If you see strength issues or jamming with sheet or halyard cleats with the tail still on a winch, I'd say that a couple more turns on the winch are a lot more important than the "correct" form of hitch.  (Unless we're talking about uncovered Dyneema or other slickery line; then you need to add covers in the way of the winch and cleat.) 

 

A correct hitch is so deeply ingrained that I always examine hitches made by others and correct them without even thinking about it.  It's amazing the varying windings and loopings dock boys can come up with at times. 



#1568 USA190520

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Posted 31 May 2014 - 06:45 AM

If you're good, you can toss in a cleat hitch with one hand and a couple flicks of the wrist-

#1569 nroose

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Posted 31 May 2014 - 05:10 PM

For what it's worth, I always thought that Allen's first method (shown in his photo) was the only acceptable method.

It's the one I was taught half a century ago as "THE ONE TRUE METHOD". I like it. I use it. It is neat, tidy and quick. But, while traveling in a far off land with different traditions, I found it doesn't work well with slippery lines on polished cleats.
+1

Generally these are used for traditional boats and dock lines. Best if the line and cleat are compatible in size. And no bite for sheets that may need to be released quickly under load. And the main beneficial feature is that they look great - very ship-shape. It would be nice to have scientific data that says it's also the strongest. And in many applications, like dock lines, these are subject to yanking over long periods of time, rather than a steady strong pull. Not sure how to test that.

#1570 Brion Toss

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Posted 01 June 2014 - 05:21 PM

Anyone who's had to deal with a foul belay under extreme loads knows how important it is to belay correctly. The trouble is that there is such a plethora of opinions on what "correct" is. Fortunately, this can be quantified. I believe that a belay, by definition, can be applied to hold any magnitude of load, up to the break strength of the rope, can be left unattended, and can be eased and cast off , regardless of load magnitude. This can be done with a variety of belay tools, impromptu and otherwise, but cleats, belaying pins, bollards, etc. are highly-evolved items; it is just up to us to use them correctly. The initial turn, touching the far end of the belay first, is key. So is making a "C" turn first, instead of going straight to figure 8's (or making an "O" turn), in order to avoid binding. And I think that a finishing hitch is important, but only if there are enough figure 8's to generate enough friction that, regardless of the load, the hitch never gets loaded. Obviously this involves skill and judgement on the part of the operator, as different loads, rope consistency and belay point characteristics affect how much friction you need.
It seems likely that the reason there are so many demonstrably lousy belays out there is that sailors seldom encounter the kind of extreme circumstances where a lousy belay can kill you. But if you always take the trouble to belay well in normal circumstances, you will automatically belay well when it matters.
PS,
In case any of you were waiting to hear about the rope tests at New England, the samples have been there for a while, but have been bumped by paying clients. They assure me that they'll be breaking our stuff soon. Stand by.

#1571 thinwater

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Posted 03 June 2014 - 01:17 AM

I thought you would all get a kick out of this. From a 1976 Sail Magazine Article on the Bicentenial tall ship get-together. A 3-strand soft shackle. The idea was old then.

 

76%27+Sail+3-strand+soft+shackle.jpg



#1572 Alcatraz5768

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Posted 05 June 2014 - 06:33 AM

I haven't seen it anywhere in this thread but does anyone have a nice splice for a spectra 12mm line to a spectra 8mm line. Both with poly covers and it has to pass through a block or two, however the strength only really has to be hand pulled. The application is the running section of my running backstays, where it needs 12mm for strength and to work in the self tailers, but it will flow much better with the 8mm. I would have the 12mm be long enough to go around the winch 4times then through the tailer t hen about 2feet extra then 30 feet of 8mm line.

Ant thoughts?

Cheers Dave.

#1573 haligonian winterr

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Posted 05 June 2014 - 12:39 PM

There's a couple of splicing threads running right now, and I swear I saw one with exactly what you're looking for...

 

Samson has this http://www.samsonrop...AUG2012_WEB.pdf that might work for you. 

 

Here we go, I think there's discussion in here http://forums.sailin...howtopic=108311

 

If you're going to use the Samson method, I wouldkeep the 12mm cover real long, then take it over the core-cross by 2' then bury the 8mm cover into it.

 

HW
 

I haven't seen it anywhere in this thread but does anyone have a nice splice for a spectra 12mm line to a spectra 8mm line. Both with poly covers and it has to pass through a block or two, however the strength only really has to be hand pulled. The application is the running section of my running backstays, where it needs 12mm for strength and to work in the self tailers, but it will flow much better with the 8mm. I would have the 12mm be long enough to go around the winch 4times then through the tailer t hen about 2feet extra then 30 feet of 8mm line.

Ant thoughts?

Cheers Dave.



#1574 allen

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Posted 05 June 2014 - 02:43 PM

^^  If I am understanding correctly why not make the entire line 8mm and add a second cover over part to bulk it up?



#1575 Reht

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Posted 05 June 2014 - 03:14 PM

^^  If I am understanding correctly why not make the entire line 8mm and add a second cover over part to bulk it up?

^^ This. If the splice is going to be in the loaded section of the line you'll want all the strength you can get. The best way of managing that is to keep the core a single line. Bulking up where it needs the extra grip is a good thing.



#1576 Brion Toss

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Posted 05 June 2014 - 03:21 PM

The good news is that NER finally broke all the shackle and splice samples that I sent in. The bad news is that there was a serious mixup in the lab, and the results are essentially meaningless. Sigh. They'll be sending more rope, and I'll be assembling more samples.
Still awaiting results on some rope seizings tests, which apparently went better. Will keep in touch.

#1577 Estar

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Posted 05 June 2014 - 07:28 PM

The good news is that NER finally broke all the shackle and splice samples that I sent in. The bad news is that there was a serious mixup in the lab, and the results are essentially meaningless. Sigh. They'll be sending more rope, and I'll be assembling more samples.
Still awaiting results on some rope seizings tests, which apparently went better. Will keep in touch.

out of curiosity, do you know what they did wrong in the testing? I am always interested to learn from other's mistakes.



#1578 JumpingJax

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Posted 16 June 2014 - 05:30 AM

In a moment of idleness - raining buckets, blowing stink - I got to looking at Evan's spreadsheet, http://www.bethandev...rope specs.xlsx , among other things.  Interesting, but it led to some other questions.  What about other diameters?  And what about variation with size of cost in relation to breaking strength?  And for a new measure, what's the cost per unit weight of line?  Does it vary with diameter?  Turned (of course) to the Intertubes:

 

For Amsteel Blue and AS-78, 7/64' to 1/4' diameters, based on physical data reported on the Samson web site and prices for Amsteel Blue from Defender and prices for AS-78 from West Marine, it turns out that the cost per 1,000 psi breaking strength is quite uniform, varying from 17 to 19 cents per 1,000 psi for Amsteel Blue and 18 to 20 cents per 1,000 psi for AS-78. 

 

From the same data, calculating $/lb. also gives a sorta flat price of from $90.00 to $108.00 per pound.   The substantial number of feet per pound and the wide range of values for the different sizes of line make this an unlikely metric of great significance in the commercial realities of product pricing. 

 

Data for STS75 and STS90 are problematic, since fewer on-line vendors carry these lines and those that do seem to have only a few diameters.  Prices are so far more variable.  I decided that an exercise like the above would be unreliable and possibly misleading.  A couple of observations, however.  These lines are "heat set under tension." As a result, these lines have been apparently pre-stretched to the point that constructional stretch is taken out which also results in a small reduction in diameter and a slight increase in weight per 100 ft. for a given end diameter.  The nature of the heat treatment is not disclosed.  These parameters may (or may not) account for (at least some or possibly all of) the higher breaking strength claimed by NE Ropes for their lines at a given diameter. 

 

It would be interesting to design a test to compare Amsteel to the STS line by pre-stretching and heat-setting Amsteel to see if it gives STS-like results when pulled.  We don't know if the heat treat and pre-stretch should be done before application of the protective coating applied at the factory.  That may prevent an effective test on our part.  While Samson probably knows, they aren't like to tell us.  And surely NE Rope knows, but they aren't likely to say either. 

 

We should be able to have a full test program designed for Evans as soon as he gets back from the Frozen North.  :rolleyes:

 



#1579 Reht

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Posted 16 June 2014 - 02:19 PM

Question to the crowd, I put together a clever system last year for some jib cars, pull one line and both cars move in tandem and should be in the same position when you tack. Unfortunately there is a discrepancy in the line lengths for each side to make everything line up, when I built the system everything was nice and even. Now after a bit of sailing it seems that the lines have settled a bit and one car is perpetually a few mm behind the other. Is the easiest/best thing to do just to pull out one splice and re-splice at the now correct length? Is it likely that the difference was caused by the line settling or the splice (ie, should I splice a little short on the new splice hoping that it settles to even)?

 

It seems like an obvious solution, but while I do plenty of splicing I've never had to pull out a splice to adjust lengths.



#1580 allen

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Posted 16 June 2014 - 02:28 PM

You didn't say what kind of line you have.  The solution depends on a lot of things that you didn't say.  If it were me, I would pull real hard on the short side and see if I can make things even again.  I had an issue once with a line that got too long after I spliced it.  There was tons of extra strength in this application so I put a figure of eight knot in the line to shorten it.  My inhauler adjusts both sides at the same time and there I have a ring with a luggage tag hitch that can be adjusted to even out the two sides.  There are lots of potential solutions depending on the details.

 

Allen



#1581 Reht

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Posted 16 June 2014 - 02:38 PM

Single-braid dyneema, think amsteel (effectively the same stuff, different manufacturer), the splices were just straight long buries because of where I was working it was the easiest near-full-strength splice to do.

 

I like the concept of running it through a ring to be able to even out the two sides without messing with the splices, I'll see if I can do something like that.



#1582 Alex W

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Posted 16 June 2014 - 04:39 PM

Reht -- look up a "whoopie sling".  It is basically a buried splice where you then re-expose the tail and can use it to adjust the splice.  You give up some strength, but it should be more than strong enough for that application.

 

I use the same thing on my 5O5 to adjust the tails of the split mainsheet.



#1583 Reht

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Posted 16 June 2014 - 06:20 PM

Alex, I use a whoopie sling on the 49er bridles, and I had considered that, but unfortunately the splice needs to run through some blocks in the deck (the system is under the deck, the cars are outside) and the extra tail of the sling in my experience gets messy around blocks.



#1584 Christian

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Posted 17 June 2014 - 03:17 AM

Question to the crowd, I put together a clever system last year for some jib cars, pull one line and both cars move in tandem and should be in the same position when you tack. Unfortunately there is a discrepancy in the line lengths for each side to make everything line up, when I built the system everything was nice and even. Now after a bit of sailing it seems that the lines have settled a bit and one car is perpetually a few mm behind the other. Is the easiest/best thing to do just to pull out one splice and re-splice at the now correct length? Is it likely that the difference was caused by the line settling or the splice (ie, should I splice a little short on the new splice hoping that it settles to even)?

 

It seems like an obvious solution, but while I do plenty of splicing I've never had to pull out a splice to adjust lengths.

a few mm's?  you need to worry about something else............



#1585 Reht

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Posted 18 June 2014 - 01:17 PM

Question to the crowd, I put together a clever system last year for some jib cars, pull one line and both cars move in tandem and should be in the same position when you tack. Unfortunately there is a discrepancy in the line lengths for each side to make everything line up, when I built the system everything was nice and even. Now after a bit of sailing it seems that the lines have settled a bit and one car is perpetually a few mm behind the other. Is the easiest/best thing to do just to pull out one splice and re-splice at the now correct length? Is it likely that the difference was caused by the line settling or the splice (ie, should I splice a little short on the new splice hoping that it settles to even)?

 

It seems like an obvious solution, but while I do plenty of splicing I've never had to pull out a splice to adjust lengths.

a few mm's?  you need to worry about something else............

A few mm difference between the jib cars on an etchells with the small jib makes rather noticeable differences in the sail's set, never mind that the 7-8mm difference is a significant amount compared to how much you tweek the cars in some conditions. When we're gearing up for major championships you'd better believe we're going to be picking at details like this.

 

Now if this were a cruising boat or a boat I go out on for kicks and giggles then I probably wouldn't even bother noticing it...



#1586 Christian

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Posted 18 June 2014 - 03:33 PM

 

Question to the crowd, I put together a clever system last year for some jib cars, pull one line and both cars move in tandem and should be in the same position when you tack. Unfortunately there is a discrepancy in the line lengths for each side to make everything line up, when I built the system everything was nice and even. Now after a bit of sailing it seems that the lines have settled a bit and one car is perpetually a few mm behind the other. Is the easiest/best thing to do just to pull out one splice and re-splice at the now correct length? Is it likely that the difference was caused by the line settling or the splice (ie, should I splice a little short on the new splice hoping that it settles to even)?

 

It seems like an obvious solution, but while I do plenty of splicing I've never had to pull out a splice to adjust lengths.

a few mm's?  you need to worry about something else............

A few mm difference between the jib cars on an etchells with the small jib makes rather noticeable differences in the sail's set, never mind that the 7-8mm difference is a significant amount compared to how much you tweek the cars in some conditions. When we're gearing up for major championships you'd better believe we're going to be picking at details like this.

 

Now if this were a cruising boat or a boat I go out on for kicks and giggles then I probably wouldn't even bother noticing it...

Bullshit - a few mm difference from side to side is nothing.  As a matter of fact you will most often have a bit of difference from side to side to make up for different twist angle in the breeze from side to side (which kind of makes matched up jib leads more of a PITA than an advantage).  If you really want to optimize you set the jib leads on each board to fit the breeze - not to fit the lead on the other board.



#1587 Reht

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Posted 18 June 2014 - 04:52 PM

 

 

Question to the crowd, I put together a clever system last year for some jib cars, pull one line and both cars move in tandem and should be in the same position when you tack. Unfortunately there is a discrepancy in the line lengths for each side to make everything line up, when I built the system everything was nice and even. Now after a bit of sailing it seems that the lines have settled a bit and one car is perpetually a few mm behind the other. Is the easiest/best thing to do just to pull out one splice and re-splice at the now correct length? Is it likely that the difference was caused by the line settling or the splice (ie, should I splice a little short on the new splice hoping that it settles to even)?

 

It seems like an obvious solution, but while I do plenty of splicing I've never had to pull out a splice to adjust lengths.

a few mm's?  you need to worry about something else............

A few mm difference between the jib cars on an etchells with the small jib makes rather noticeable differences in the sail's set, never mind that the 7-8mm difference is a significant amount compared to how much you tweek the cars in some conditions. When we're gearing up for major championships you'd better believe we're going to be picking at details like this.

 

Now if this were a cruising boat or a boat I go out on for kicks and giggles then I probably wouldn't even bother noticing it...

Bullshit - a few mm difference from side to side is nothing.  As a matter of fact you will most often have a bit of difference from side to side to make up for different twist angle in the breeze from side to side (which kind of makes matched up jib leads more of a PITA than an advantage).  If you really want to optimize you set the jib leads on each board to fit the breeze - not to fit the lead on the other board.

I'd rather have the 2 sides even than an arbitrary difference between them, sure it's faster with with sheer *technically* to have them in differing positions, but the windsheer up a small jib plus the fact that the system under the deck keeps them matched and it would have to be reinvented to have the sides individual. If you're taking sheer into consideration, what if the difference in position is the opposite of what you want? You're going to adjust it even more.

 

Plus, fixing it makes the foredeck guy stop complaining about it, so that's an intangible benefit. I ended up building a system under the deck where (within small margins) I can adjust where the cars are relative to each other, much nicer than re-splicing.

 

Done with this derailment, back to interesting discussion.



#1588 allen

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Posted 18 June 2014 - 05:21 PM

 I ended up building a system under the deck where (within small margins) I can adjust where the cars are relative to each other, much nicer than re-splicing.

 

Done with this derailment, back to interesting discussion.

Interesting discussion would be what does your system look like?  The "tied off" point is a luggage tag with a figure of eight knot to lock it.

 

Here is my inhauler system:

inhauler.png



#1589 Islander Jack

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Posted 18 June 2014 - 05:54 PM

The "tied off" point is a luggage tag with a figure of eight knot to lock it.

 

Not an Alpine butterfly loop?



#1590 allen

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Posted 18 June 2014 - 06:14 PM

^^ Alpine butterfly loops close up over time in Amsteel and would be difficult to get the lengths exact that way in any event.  What I do is form the luggage tag without the figure of eight knot and adjust the two sides to be the correct length.  If you read my web page, you will see that the two sides need to be different lengths because the pad eye turning block is off center to allow the lines to clear the mast.  Once things are adjusted, the figure of eight keeps it that way without changing the relative lengths. 

 

Allen



#1591 Estar

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Posted 27 July 2014 - 10:53 PM

I am working my way back (south) from greenland (todays, in Nova Scotia, gribs shows SWly winds until august 8th - sigh) and just got a spot of wifi.

 

Brion - any update on the NER testing?

 

 

The good news is that NER finally broke all the shackle and splice samples that I sent in. The bad news is that there was a serious mixup in the lab, and the results are essentially meaningless. Sigh. They'll be sending more rope, and I'll be assembling more samples.
Still awaiting results on some rope seizings tests, which apparently went better. Will keep in touch.

 

Jumping . . . . Brion made me some pieces in the NER STS heat set stuff.  In my tests it performed (as a % of rated strength) similarly to amsteel, except (like dux) it was harder to make '100% strength' splices (seems more sensitive to braid distortion).  To test bigger diameter dyneema stuff I would need to build a higher strength bench including getting a more expensive load cell - so far everything I have seen suggests pretty good results scaling thru 'normal yachting' sizes so I have not yet seen a good reason to go to that effort/expense. 






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