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5mm Hampidjan Dynice Dux

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(@revintage)
Posts: 281
Mate
Topic starter
 

Anyone have experience of this rope?

Bought a few meters to use as forestay on my Nacra.

A little puzzled as the rope is really fat at 6.5mm and when spliced just below 10mm. Haven´t stretched or loaded it though.

Don´t expect the rope to be much thinner as it is extremely hard compared to other Dyneemas. The splice will probably thin out to something like 8mm.

I usually prestrech at ca 4-500kg using my 10:1 mainsheet system and setting up between two trees.

Edited by revintage on Jun 27, 2018 - 05:57 AM.

 
Posted : June 26, 2018 11:56 pm
MN3
 MN3
(@MN3)
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I have sailed a 1/2 dozen times on a f31 tri that had it's shrouds replaced with this line
same size i think
it is pre-stretched and heat treated to reduce creep

Line is "size rated" under load - so 5 mil will be fatter when not under load (being stretched)

MN3

 
Posted : June 27, 2018 1:40 am
Mike Krantz
(@mikekrantz)
Posts: 99
Mate
 

5mm is overkill. You're replacing 5/32 1x19 wire that is rated at 1,493kg with a 5mm product that is rated at 3,810kg

I use Marlow D12 Max SK99 for standing rigging applications. It's manufactured using the same heat treat process as Dux, but comes in smaller diameters.

You should be using 3mm D12 Max SK99 that is rated at 1,790kg. I replaced all of the standing rigging on an Nacra 20 and reduced the weight of the standing rigging by 75%.

 
Posted : June 27, 2018 4:37 am
(@revintage)
Posts: 281
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Topic starter
 

MN3,

Wonder under what load this sturdy rope is down to 5mm 😉 .

Mike,

It wasn´t about rating needed, it was about the delivered 5mm being 6.5mm without load. Expected it to be a 5mm line going down to 4mm when loaded like the other Dyneemas I have tried. Hampidjan probably did it the other way specifying diameter under load.

The rest I am aware of.

I use a std Liros SK78 4mm on my 16sqm dinghy, the rope is quite loose without load(unlike the Dux), going down to 3mm with 100kg load. Doesn´t loose tension when stretched. Creep has been no object as the rig is without tension when on land.

If I wanted a smaller diameter, Liros D-Pro Static would be my choice.
https://www.liros.com/en/products/productfinder/details/detail/liros-d-pro-static.html

Edited by revintage on Jun 27, 2018 - 01:17 PM.

 
Posted : June 27, 2018 6:13 am
MN3
 MN3
(@MN3)
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revintage wrote: MN3,
Wonder under what load this sturdy rope is down to 5mm 😉 .

this much - thats dux on a 45' rotating mast (all colligo lines and fittings)

Actually Mike K knows. He has a pull machine to test these kind of things - he knows real numbers

Edited by MN3 on Jun 27, 2018 - 07:49 PM.

MN3

 
Posted : June 27, 2018 1:42 pm
(@revintage)
Posts: 281
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Topic starter
 

Will soon know ballpark numbers, testing at 100kg and 400kg 😉 .Edit:

Was out and tested an hour ago. Used my 10:1 mainsheet system and pulled as hard as I could:
Rope 5.5mm
Splice 9mm

Still to fat for me, as I want 4mm when stretched. Will order 5mm Liros D-pro Static. The answer lies in the weight Dux 5mm is 27gr/m Static is

Edited by revintage on Jun 28, 2018 - 10:30 AM.

 
Posted : June 27, 2018 11:55 pm
MN3
 MN3
(@MN3)
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Was out and tested an hour ago. Used my 10:1 mainsheet system and pulled as hard as I could:
Rope 5.5mm
Splice 9mm

Did the trees move? 🙂

5mm Liros D-pro : sounds like nice line ..

I use a turnbuckle in my rig so creep isn't really an issue for me...

hmmmm
maybe i will splice my next forestay

MN3

 
Posted : June 28, 2018 12:11 pm
Philip
(@p-m)
Posts: 916
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mikekrantz wrote: I replaced all of the standing rigging on an Nacra 20 and reduced the weight of the standing rigging by 75%.

I think that this might be my boat. I think the weight savings was even more. I will look for pics. Mike is expert on this and highly recommended.

I will say performance gain was incredible. The rig is stiffer, boat accelerates faster, and less helm due to the elimination of weight up high near the hounds. I don't know why anyone wants wire anymore. This is the schit . . .

Philip

 
Posted : June 29, 2018 4:54 am
MN3
 MN3
(@MN3)
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I don't know why anyone wants wire anymore. This is the schit . . .

my hesitation would be line chafe aloft (i know you said you use a jacket up there) and vandalism by some douche with a sharp knife on the beach when parked overnight

MN3

 
Posted : June 29, 2018 6:52 am
Philip
(@p-m)
Posts: 916
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MN3 wrote:

I don't know why anyone wants wire anymore. This is the schit . . .

my hesitation would be line chafe aloft (i know you said you use a jacket up there) and vandalism by some douche with a sharp knife on the beach when parked overnight

Good point regarding overnight on the beach. Chafe is not a problem. If it is the party is doing something wrong.

I use a sacrificial braided cover and even it's not chafing. Might not use the cover next go around.

Philip

 
Posted : June 29, 2018 8:28 am
MN3
 MN3
(@MN3)
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cat sailing porn: http://www.colligomarine.com/beach-cats/

MN3

 
Posted : June 29, 2018 9:35 am
(@martin_langhoff)
Posts: 235
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How about creep? I have a foiling beachcat that's very finnicky with rig tension; I'm a lazybum that doesn't want to be re-checking with the loos gauge on each outing...

 
Posted : June 30, 2018 8:02 am
MN3
 MN3
(@MN3)
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Creep sizing.

Our creep target is less than 0.1” per year of creep. We use the static load or pre-tension that a rig sees as the load number to use for creep. Most sailboats sit upwards of 95% of their time so Dynamic loads are ignored, most of the time. This has proved successful as we have rigged more than 750 boats around the world at this time. If you have a boat that you feel will have more use and dynamic loads will be more significant, simply oversize the line to accommodate that usage. Use the printable creep table here for determining your creep loads and thus the line size you need based on creep. Contact us here for help in sizing for creep.

http://www.colligomarine.com/fundamentals/

on the tri - they hand tighten each shroud with a load spreader
i do it with my forestay/Portuguese turnbuckle ... (but i'm not racing nor foiling)

this isn't my friend's boat: but that sam load spreader with some 3mm dux

MN3

 
Posted : June 30, 2018 8:48 am
(@revintage)
Posts: 281
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Topic starter
 

With a beachcat creep shouldn’ t be an issue, as the rig is ”untensioned”after each raceday. With a creep of 0.1” a year under constant tension it should be unmeasurable on the typical beachcat.

 
Posted : June 30, 2018 9:14 am
(@revintage)
Posts: 281
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Topic starter
 

Still to fat for me, as I want 4mm when stretched. Will order 5mm Liros D-pro Static. The answer lies in the weight Dux 5mm is 27gr/m Static is

Missed the last of the sentence, should be: Static is 13gr/m with a breaking load of ca 2400kg.

 
Posted : July 1, 2018 5:11 am
(@martin_langhoff)
Posts: 235
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Is there a way to measure tension? Say, some specific wire lines need to be in the 18-20 range in loos gauge. I check periodically that the rig has that the right tension. How would I do this with dyneema based rigging?

 
Posted : July 1, 2018 11:53 pm
(@revintage)
Posts: 281
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Topic starter
 

Replace one of the Dyneema shrouds with 19x1 stainless steel and compare with the other, to get a reference for your tensiometer.

Also Colligo has conversion a table for Dux/Loos: https://static1.squarespace.com/static/556621c8e4b02628a8d3bde8/t/55c110bde4b056e19ca78068/1438716093298/LoosGaugeCals.pdf

Another way could be to hang a Dyneema line from high up in a tree and load with different weights hanging at the lower end, to calibrate the Loos or RigSense.

Edited by revintage on Jul 03, 2018 - 02:10 AM.

 
Posted : July 2, 2018 8:21 am
samc99us
(@samc99us)
Posts: 574
Chief
 

Dyneema rigging is fine on a race boat where you are trying to save every ounce aloft and checking it regularly.

I would not advise using this on a recreational boat, or one that is kept mast up 95%+ of the time and you don't want to tip for regular inspections. Why? Chafe aloft is a real concern, sure it can be mitigated but do you really want to worry about it? Then you add the creep issues mentioned and its just not worth it on a recreational ride.

If you want to save weight and avoid the complications of dyneema, look into dyform. We still use this on A-Cat diamond wires and I have a set of dyform shrouds that are nice, relatively light and don't change tension over a day of sailing or a week of sailing for that matter.

 
Posted : July 3, 2018 3:26 am
(@revintage)
Posts: 281
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Hi Sam,
No need to worry about chafing aloft if you take the right precautions with a rotating mast. Either add shrink tube or rope cover the first 20cm. Also Dyneema takes a lot of abuse before anything gets dangerous. But for me the big win is you don’t have to go to a rigging shop if you want to change anything, just alter a splice! Win-win with lower weight and lower cost 😉 . About creep, tell me more about the issues, actually I don’t follow you there? Could it be some recreational beachcat sailors are stupid enough to untension their rigs after the occational ride?

 
Posted : July 3, 2018 11:57 am
samc99us
(@samc99us)
Posts: 574
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revintage,

Chafe is certainly manageable but can appear where you may not think; for example it shows up on dyneema trap lines where the traps cross the shrouds (think long double wire spinnaker runs).

While your statement is partially accurate regarding avoiding a rigging shop, its not 100% true. In order to build a correct set of shrouds/forestay for a beach cat, you really need to load the finished product with a thousand or more pounds of force (at least 50% of the rated breaking strength of the line) to set the splices. Otherwise you will be constantly adjusting the rigging for the first few outings and can end up in a situation where the shrouds are too long and you need to completely re-splice. Most folks don't have a hydraulic press available. You can use a mainsheet system as an alternative but need a spot to rig it.

Creep can occur over time as well and most shroud systems are prone to changes in temperature (wire length increasing/decreasing). Point is you may show up to the boat one day and its okay, and a week later its no longer tensioned properly. Most rec sailors don't throw a loos gauge on the boat before they go sailing (heck many club racers don't either!). That's my point; with dyneema rigging you are more prone to error across the first few sails than with wire, which generally sets on the first outing and you are good for the life of the rigging.

 
Posted : July 5, 2018 6:32 am
(@revintage)
Posts: 281
Mate
Topic starter
 

Hi Sam,

I agree completely on both your latest posts, but any person should avoid doing things they don´t fix. We shall not assume people don´t use their brains. If you are thinking of me, I am doing this of curiosity and to learn. The idea of not using Dyneema on a recreational funboat is a really good advice.

1 If one don´t forget to put on the thinking cap it will be solved, even if this could be considered to be a nobrainer.

2 Same as 1. One could also do like Nacra did earlier and use NICO-pressings. But to press a 4mm 19part is not so easy. Lots of swearing before they´re done.

3 Same as 1. I am surprised people don´t "unstretch"(don´t know the english word for it) their rigs after racing/sailing, though. Even in my Tornado-racing days in the 80´s this was common practice. I also expected people had invested in a tensiometer. I am now upgrading my 7:1 "boatbreaker" for the forestay to 10:1, to make things easier.

Synthetic rigging is quite new to the market, so everyone will surely learn and the material will also get better and better.

Will keep a close eye on what happens to the Dux "Fatty". Have also ordered 5mm Liros D-Pro Static to evaluate. Will also try to do a conversion table for my Rig Sense for static tension of the types I use. I have two smaller dinghys and the catamaran to deal with, all with different types of Dyneema rigging. The 49er I am rebuilding will keep its 3mm Dyform shrouds but will be tried with the 5mm Liros as forestay as this anyway needs to be replaced.

Edited by revintage on Jul 06, 2018 - 05:14 AM.

 
Posted : July 5, 2018 11:29 am
MN3
 MN3
(@MN3)
Posts: 7090
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I also expected people had invested in a tensiometer

Most people on this site are recreational sailors whom have 20 year-old legacy boats whom don’t care own a loos gauge, nor know how to splice – nor interested in having to resplice their rigging after creep/stretch come into play

“No Brainers” = your knowledge base – not everyone here is an engineer
Your desire to optimize to the fullest extent isn’t shared by everyone on here – many recreational sailors sail less than a dozen times a year

MN3

 
Posted : July 6, 2018 7:48 am
(@revintage)
Posts: 281
Mate
Topic starter
 

Hey MN3,

Then, those who are not interested, will not care about my posts. What about those who want to learn more, like me, should we be excluded?

Thought this forum was for everyone, like Sam, Mike, you and others, for those who are more technically interested?

Sorry if this is not to your liking, maybe subtle language problems?

Edited by revintage on Jul 06, 2018 - 02:34 PM.

 
Posted : July 6, 2018 8:25 am
MN3
 MN3
(@MN3)
Posts: 7090
One Star Admiral
 

my statement was mostly to emphasize that many people here do not optimize to the level you do

your input is valuable and appreciated
NO ONE is excluded

MN3

 
Posted : July 6, 2018 8:40 am
(@revintage)
Posts: 281
Mate
Topic starter
 

Thanks MN3,
Doing what I can to have a new, nice beachcat journey.I love this new material world, since I left the cat world and now returned more than 30 years later, as retired from boring daytime work. Still curious, though!

Edited by revintage on Jul 06, 2018 - 04:31 PM.

 
Posted : July 6, 2018 10:28 am
(@cholley12)
Posts: 148
Mate
 

For fear of bringing up a dead topic, I actually use this stuff on my boat. Ill have to go out tomorrow morning and do some pictures as my boat is at the fiberglass doctor getting a bottom job done and i have the mast in the backyard, so you will have to bear with that aspect. However, I love the stuff, it took one day sailing in high wind to settle the little settling that it need to seat, since then it hasnt stretched one bit. It also has allowed me to set the boat up quicker and with less hassle.

 
Posted : January 23, 2019 6:01 pm
samc99us
(@samc99us)
Posts: 574
Chief
 

Lars,

You are the exception rather than the rule I would say. Otherwise Hobie wouldn't have developed the comp-tip back in the early 80's and the General Aviation Manufacturers wouldn't have been taken to the ringer by the families of loved ones lost in airplane accidents that in most cases were their owners faults. Hence we have diminishing sales of new beach cats and new four place airplanes that cost >$500k rather than~3x the cost of a standard SUV like they did back in the 60's.

Anyway, back to dux, I am certainly interested in what you determine during sailing. I agree that taking rig tension off overnight is prudent (even carbon isn't happy in compression) but also not the easiest thing to do all the time. Our biggest issue with the stuff at present is it sings at higher speeds which is really annoying when trying to think about tactics etc.

 
Posted : January 25, 2019 4:11 am