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PostPosted: Sun Apr 20, 2014 4:07 pm 
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The Line Guide specifies 3/16" line, but there are no other details.

I'm wondering about the following:

  • What rating (breaking strength)?
  • Braided or twisted?
  • How much stretch is desirable?

Any suggestions for a good brand/type for recreational sailing?


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PostPosted: Sun Apr 20, 2014 5:41 pm 
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Location: Clinton Lake, KS
I just bought 3/16 New England V100.. It is vectran core with a poly cover.. The vectran means in the same size line it has to be more than up to the task.
I have sailed on it once and really like it.. Easy to adjust and simply didn't creep or require any readjustment due to stretch.

The only real problem I had was getting the cover back over the eye splice I made at the lower block.. Just wish class rules would allow me to strip all that extra cover where I don't need it.. :twisted: :)


And no idea what the stock line is these days... But word is it is a bit "slippery" in the Cam cleat setup.. So I didn't even bother with it, and let it go with my old boat.


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PostPosted: Mon Apr 21, 2014 4:53 am 
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Flying Hollander wrote:
The Line Guide specifies 3/16" line, but there are no other details.

I'm wondering about the following:

  • What rating (breaking strength)?
  • Braided or twisted?
  • How much stretch is desirable?

Any suggestions for a good brand/type for recreational sailing?

Last two questions first:
- Twisted line has no place on a Hobie Cat, except maybe as a towline.
- Minimal stretch is most desirable
- Almost any 3/16" synthetic line will have sufficient breaking strength (1500+ lbs)

Which halyard are you using? Wire or Aussie?

For the tail on the wire halyard, almost any braided line will do, but you want something flexible that cleats easily.
New England Ropes Sta-Set is a good choice. It's a polyester double braid.

For an Aussie halyard, things get more complicated and expensive, depending on how much you want to eliminate stretch (very undesirable on the Aussie system).

The stock line is a Dyneema single braid, which as Ron noted, has a waxy/slippery feel to it - and it likes to creep in the cleat. But it's relatively inexpensive and very flexible. Vectran cored line is not as flexible, but the polyester cover grips the cleat well. Both are about $1 / foot. At the other end is New England's Heat Set Dyneema, which is about $2 / foot, but because it's so strong, you could downsize to 1/8" - which still has a 5,200 lb tensile strength.

This page has all the options - http://www.apsltd.com/c-9562-line-by-material.aspx


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PostPosted: Thu May 15, 2014 10:23 am 
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Location: Indianapolis, IN
My question is, does tensile strength equate to stretch? Are they at least proportionate? Higher tensile strength = lower stretch?

I'm looking at getting the 4mm (5/32") FSE Robline Dinghy Control line as an aussie halyard. It's close to half the price if I go down 1mm.

Tensile 5mm v100: 2500lb $0.94
Tensile 5mm dinghy control: 2700lb $0.97
Tensile 4mm dinghy control: 1574lb $0.60

Am I pushing it too much or would I be fine going 4mm?

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PostPosted: Thu May 15, 2014 11:29 am 
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PurdueZach wrote:
My question is, does tensile strength equate to stretch? Are they at least proportionate? Higher tensile strength = lower stretch?

I'm looking at getting the 4mm (5/32") FSE Robline Dinghy Control line as an aussie halyard. It's close to half the price if I go down 1mm.

Tensile 5mm v100: 2500lb $0.94
Tensile 5mm dinghy control: 2700lb $0.97
Tensile 4mm dinghy control: 1574lb $0.60

Am I pushing it too much or would I be fine going 4mm?


I wouldn't just because I placed a priority on low stretch, and 5/32 I thought would be harder to handle. I would think 1574 lb should be enough... but still...

What is going to annoy me is if everyone ends up going to line like this and we can't strip the cover off where we don't need it. :D


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PostPosted: Thu May 15, 2014 11:38 am 
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Ron, you're saying that V100 is lower stretch than this dinghy control line? I believe that but where are the numbers that show how much stretch each line has? Dinghy control has a higher tensile strength....

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PostPosted: Thu May 15, 2014 11:51 am 
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And how much handle do we really need in a aussie jib halyard? To tighten I use mmadge's suggestion in another post:

mmadge wrote:
Easiest to do when going down wind.Need to use Big Boat Halyard technique.What I mean is you jump the halyard on the mast between the blocks and the horn cleat on front of mast.Just pull it out from mast then take up slack on the Halyard line just after the cam cleat.Cleat it on the cam cleat ,repeat if needed and finally cleat it down on the horn


I don't imagine it would be that hard to adjust even with a thin diameter line.

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PostPosted: Thu May 15, 2014 12:40 pm 
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PurdueZach wrote:
Ron, you're saying that V100 is lower stretch than this dinghy control line? I believe that but where are the numbers that show how much stretch each line has? Dinghy control has a higher tensile strength....



It is my understanding that the SK-75 core has a slightly higher breaking strength at the same diameter, but the vectran is slightly less susceptible to creep. I imagine the differences are nearly imperceptible for the purposes of a H16 Jib haylard.. But still.. That was why I went with it.. What exactly the numbers are for percentage of creep at what load levels... I don't know.




I play with my Jib halyard setting all the time on the water. Probably as I 'get better' I will play with it less, but even very small changes in the setting make big differences in how the boat feels and reacts.




I have wondered though.. If you had a line which would reliably and consistently stretch (not creep) if the window of 'proper' adjustment would be a bit wider.. As in you could run a bit more rig tension through a 'wider' window of sail trim. My thought is that it would give a wider range of main sail trim before really cranking on the jib luff....


Something else I was thinking about.. With the mast raked all the way back.. And the jib halyard trimmed so that main sail leach tension is roughly the same at the block to block position.. Wouldn't the boat be carrying less power with the shroud 3-4 holes up than it would be running in the bottom hole? This because the mast would be able to fall off to leeward more? I always hear people talking about 'shortening' the shroud to 'de-power'.... Yet if you are letting enough rig tension off to go block to block, at the point wouldn't you be de-powering' by letting out some shroud? Or would the mast really fall forward enough even sheeted block to block to move the center of effort to far forward to make that effective... (I am going to have to get some quick pins and play around on the water one of these days.)


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PostPosted: Fri May 16, 2014 10:51 am 
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Ron: Please let me (but none of my competitors) know when you figure this out!

I understand that generally you want the mast raked further forward downwind and vice-versa. However, loosening the jib halyard really just loosens the rig so the mast leans further downwind (whichever direction that is), right?

So do you sheet harder to keep the mast from leaning further to leeward when going upwind? (When I run a loose rig, I can't point for anything with the jib luff bending off so much.) What if the conditions are lighter, and you really don't want to sheet hard?

Downwind do you tighten the halyard to force the mast forward?

Sometimes I feel like I know less now than when I started!

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Hobie 16


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PostPosted: Fri May 16, 2014 5:31 pm 
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rattle 'n hum wrote:
Ron: Please let me (but none of my competitors) know when you figure this out!

Sometimes I feel like I know less now than when I started!


Gawd... I know that feeling!!!!!


Quote:
Downwind do you tighten the halyard to force the mast forward?


Even though I might be ranked 36th last year :D :P (the HCANA needs to get their butt in gear given an idiot like me can make that happen :P ) Don't go thinking I know how to seriously kick ass at a regatta just yet. I pretty much have all the pieces, but don't always put them together.. One event I am right on Jim Sohn's rudders the whole day... and the next don't even seem to be playing the same game.. Or even worse beat a bunch of great sailors to A mark only to blow it on the way down and back up again...


But... Downwind I don't usually pull the halyard.. What I like when it is light enough to think about tinkering with the Halyard is the Jim sailing position. Sort of laying down with a foot on the boom to keep mast rotated.. From that position it is pretty easy to simply reach up and grab a handful of jib halyard and just hold it.. But I usually don't.. What I find is that if I want to add rig tension and stand the mast up it really flattens to jib shape. It really feels like there is a narrow window in which one might bother with it. When it is really, really light my priority is being as smooth as possible and not bouncing the boat. Wiggling around playing with something I find is rarely worth the speed you think you might pick up.



Quote:
I understand that generally you want the mast raked further forward downwind and vice-versa. However, loosening the jib halyard really just loosens the rig so the mast leans further downwind (whichever direction that is), right?


Basically.. but my thinking has shifted more towards obtaining what sail shape at what sheet tension with the center of power as far aft as possible rather than concerning myself primarily with mast rake, other than I seem to try and run as much as possible.


The mast is going to fall of further to leeward with less rig tension though... Hence my thinking that if you are going to run a loose rig and sheet block to block I THINK (and could be horribly wrong) that there MIGHT be something to be gain by letting some shroud out. But I really need to play with it on the beach tomorrow and see how far forward the mast might really roll...

Quote:
So do you sheet harder to keep the mast from leaning further to leeward when going upwind? (When I run a loose rig, I can't point for anything with the jib luff bending off so much.) What if the conditions are lighter, and you really don't want to sheet hard?



Trick question! :lol: I am always oversheeted trying to convince myself to sheet out. :lol: No seriously think about the arc the shroud is going to guide the mast through.. As you sheet in and pull rig tension on by sheeting in the mast is pulled aft against the jib halyard. This should also cause the mast to fall to leeward as the 'hounds' come closer to being lined up with the shroud. This is why I think one might really further depower the boat by not dropping holes on the chainplate, but instead going up a couple and loosening the rig when it is really, really honking. This given you can sheet tight enough to flatten the main and the jib. I just caution that if the mast is going forward faster than is it dropping to leeward you wont' be 'depowering' in a way your H16 is going to be happy about even if you are spilling air, the center of power could be moving forward...

Then again most people just stay on the beach in the type of conditions I am taking about tuning for... Not me.. Last week was 24mph gusting to 31mph.. And I was flying solo! Broad reaching in those conditions is unbelievably awesome! I need to put some anti skid something on my rudder castings :twisted:



And yes... When it is light (which I am actually pretty decent in light conditions.) my setup is closer to my heavy air setup.. A looser rig... Sometimes a bit more downhaul to pull the leech in at the top of the sail.... :wink: (seriously play with it... and sometimes do everything 'by the book' and then pull one thing out of whack and look up :) ) Sheet both main and the jib very softly. Leave the sails with nice big fat curves in all the right places and handle them softly to keep air attached. Sheet in to flatten in the puffs and don't forget to let them out on the other side. This is what I am terrible at in medium conditions. A oversheeted stalled sail is MUCH less powerful than a undersheeted sail.... (which FYI is why if you can, when it is honking it helps to be oversheeted sometimes... :) )


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PostPosted: Sat May 17, 2014 5:47 am 
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Sorry about the hijack, OP!

Ron: Thanks for sharing your thoughts. I posed similar questions on the racing forum a while back, and all the rock stars clammed up, so I'm glad to hear from No. 36!!! :lol:

I don't have the adjustable jib halyard setup and have been trying to determine if I could actually benefit from it if I got it. I have come to accept that, while I can daysail and have a blast in the big stuff, I don't race very well in it, and probably never will. And the last thing I need is another string to pull and thing to remember racing around the buoys. However, I do quite a bit of distance racing on the Gulf Coast where one might be on all points of sail in a wide range of wind speed during a given day. One is often on the same tack for long periods of time, too, where fiddling with another string wouldn't be much of a problem.

I already do a lot of the things you suggest for trying to figure things out, but you have given me some others to consider. A big problem with discussing stuff like this on the forum is that there are so many variables and differences of experience regarding how tight is tight, what constitutes light, medium, and heavy air, etc., so I really appreciate your explanations. There just don't seem to be many universal truths with these boats, but I guess that's one reason I like them!

I'm thinking I'll hold off on the adjustable halyard setup up for a while, and maybe put those funds toward a new set of sails. :)

Thanks again!

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Hobie 16


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PostPosted: Sat May 17, 2014 6:28 pm 
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PurdueZach wrote:
My question is, does tensile strength equate to stretch? Are they at least proportionate? Higher tensile strength = lower stretch?
The short answer to your question is, "no".

Stretch depends entirely on the material. Stretch is usually expressed as a percentage of length at a specific tension (usually the working load). This is a pretty good illustration of the various line type's stretch:
Image

Some lines (like Dyneema) creep - they slowly elongate under tension and will never return to their original length when the load is removed.


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