Synthetic rigging properties?

Discussion in 'Sailboats' started by Gashmore, Sep 2, 2008.

  1. RHough
    Joined: Nov 2005
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    Location: BC Summers / Nayarit Winters

    RHough Retro Dude

    LOL! Yep ... those are the ones.

    Mama sees the yellowing cover and the rust stains and since all the crap on the boat has rust stains no thought and no budget is given to it ...

    Show Mama a threadbare pair of pants and she can equate the "fuzzy" lifelines with "worn out, time for new ones". Hell Mama can even do the splices and lashing herself ... have you seen the manual crimps that Papa did in the last set? :D That is damn scary!

    Not a Panacea by any means, but a more viable option now that there is at least some data to evaluate.

    R
     
  2. mojounwin
    Joined: Dec 2004
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    Location: Queensland, Australia

    mojounwin Junior Member

    Any updates on the use of Dynex Dux for standing rigging?

    Cheers
    Mojo
     
  3. jfranta
    Joined: Sep 2008
    Posts: 16
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    Location: Mesa AZ

    jfranta Junior Member

    Colligo Dux Standing rigging

    Hi Mojo, we have continued to rig boats, monohulls and multihulls. 65' MacGregor just completed in the Caribbean. Many large cats as they are just crying out for a synthetic solution, for both function and cost. In addition we have rigged the diamond stays on a number of boats now and that application is working great and a validation of our sizing process for creep as the static loads are generally high on diamonds. Spreader ends are turning out to not be as big of a challenge as previously thought, most can be modified and some need to be retrofitted. We are also doing alot of boats now with turnbuckles as we can splice to a specified length with very little variation and good accuracy. We are rigging an Open 60 now with a mast ram that has extremely high pretension requirements and this has really presented a challenge for us to design around the creep. In addition, it is an offshore boat, so the dynamic loads will have quite a time value to them so we have to factor those in also. The designer has provided us with all the loads and that certainly makes it easier.
    We are continuing to learn more about dyneema and its wonderful properties but, more importantly, how to design around its limitations. Its a great material but it certainly puts more responsibility in the hands of the sailor, especially for chafe inspections. For sizing standing rigging with Dux we are using a template of properties in decending order of priority.

    1. Stretch
    2. Creep
    3. Chafe
    4. UV resistance

    As data comes in, the UV concern is becoming smaller and smaller. Initially some UV damage is experienced but then the material becomes relatively opaque to UV so the rate of damage slows down considerably. We have seen first year damage as high as 15% of Mean Breaking Load. But, couple this with the fact that when we size for stretch and creep the line is 2-5 times stronger than the steel equivalent so the factor of safety is high. Based on UV limitations, we think that we will probably end up with a recommended 8 year replacement interval (in the tropics) which is similar to steel. Covered Colligo Dux Rigging is an option also and makes for an even longer replacement interval than steel.
    For Chafe, IMO, Dux is the toughest synthetic line you can get. For example, we are using ceramic knifes to cut the line and can ussually do about 10 splices on 9 mm line before they need to be sharpened. These are knifes that the manufacturers say never need to be sharpened! Having said that, Dux is certainly not as tough as steel. We see this as the biggest pardigm shift that is needed when going to synthetic standing rigging, it needs to be inspected regularly. When sized correctly (2-5 times stronger than steel) you certainly have a relatively large window of opportunity to see chafe issues and address them. The good news is our style of synthetic is easily inspected and chafe issues are highly visible.
    Stretch and Creep are issues that need to be specifically addressed in the design (sizing) phase but can easily be designed around.
    The other really important fact here is the the end terminations need to be sized such that you can get the most from the line to keep the safety factor up (for reasons stated above). A minimum 5/1 bending ratio is needed on all dyneema products to retain minimum 80% of break strength. Most of our products are 7/1 or higher. I was in St Malo for the start of the Route Du Rhum and it just made me cringe to see how dyneema was abused. It was spliced to all sorts of things, rings, padeyes, etc. that were mostly really too small, this is fine for race boats (especially running rigging) that rerig before every race and inspect often but to transition this material into the cruising world the high factor of safety is crucial, especially in standing rigging. In my mind the high factor of safety is the big enabler of this material as it buys you time to deal with the chafe and UV issues, and gives you a big warm and fuzzy when moving to a new technology. I tell customers all the time "your rig is not going to fall down, if we don't size it correctly you might have some performance issues like stretch or creep but it won't fall down".

    Notice, also, that breaking strength is not on our list. This is generally a box that we check off when sizing the line (is it strong enough?) but it is never the driver. We do not size Dux or any Dyneema for breaking strength as the other parameters are the limiting ones.
    One other issue that we have run into is discontinuous rigging. The best way to take advantage of synthetic rigging is to have a continuous rig. In fact, discontinuous rigging leads to so many end fittings that the amount of complications in the rig, windage issues, tensioning, etc start to overcome the weight savings factors of going to synthetic.

    Sorry about the long windedness here. I hope this helps and I certainly hope this does not lead to any caustic replies. I don't mind professional feedback, I even welcome constructive criticism as this is a new technology, but lets keep it professional.

    John Franta, Colligo Marine
     
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  4. RHough
    Joined: Nov 2005
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    Location: BC Summers / Nayarit Winters

    RHough Retro Dude

    I don't make a habit of quoting an entire post, but this one is an exception. As a very vocal and caustic doubter, I was very hard on John and Colligo. This post shows that he is truly a professional and is taking the right approach (IMO).

    His integrity has me looking for an application to use his products. The W17 trimaran I'm planning to build will use his product.

    His comments about race rigs and the abuse of the material are exactly correct and I find his efforts to develop sound cruising guidelines and good hardware are admirable.

    I would not hesitate to use or recommend John and Colligo for standing rigging.

    Randy Hough
    retired rigger
     
  5. Gashmore
    Joined: Feb 2008
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    Location: Macon, GA

    Gashmore Junior Member

    WOAH! Been to busy working on the boat so haven't kept up with this for a while but if we can convince RHough there may be hope for peace in the middle east! :D
     
  6. RHough
    Joined: Nov 2005
    Posts: 1,792
    Likes: 61, Points: 0, Legacy Rep: 793
    Location: BC Summers / Nayarit Winters

    RHough Retro Dude

    LOL!

    Well, after watching this evolve since this thread was started the whole thing has gone from marketing hype to believable numbers and reasonable expectations. I'm damn impressed.

    When I'm vocal about doubts and the questions I raised have been dealt with I have to stand up and say so.

    Every time I look at the site there are new goodies available to make the system work. These are earmarks of someone working hard to improve. One of challenges Colligo faces is solutions to make direct replacement of SS wire easy. Fittings that allow that make the packages viable.

    The emphasis on comparable stretch rather than strength is great. The material is so strong that when is is sized to have the same stretch as 1x19 wire or Nitronic Rod, the safety margins go up and creep becomes much less of an issue.

    Most wire rigs have eyes and pins or T-balls at the mast. I don't think it will be long before Colligo will be able to ask not just for pin to pin lengths but also ask for pin sizes and provide truly plug and play rigging replacements.

    Colligo seems to be progressing and expanding during trying times. That says a lot.

    R
     
  7. Strawberry
    Joined: Jan 2011
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    Location: London

    Strawberry New Member

    So how about the release of SK78 and SK90, both stiffer and stronger than the SK75 Dyna Dux is made from.
     
  8. brian eiland
    Joined: Jun 2002
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    Location: St Augustine Fl, Thailand

    brian eiland Senior Member

    Dyneema Recruiting Worldwide

    DSM Dyneema, producer of Dyneema®, the world’s strongest fiber™, is recruiting the globe for 40 ‘Skippers’. They can test running-rigging made with Dyneema® fiber and share their experiences through social media.

    If you are selected to join the 2011 Dyneema® Experience Team, we will re-rig your boat completely free of charge with ropes made with Dyneema®. All we ask of you is that you test and experience rigging with Dyneema® and share this with us, your friends, family and other sailors worldwide,

    http://www.dyneemaexperience.com/home.htm
     
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  9. mojounwin
    Joined: Dec 2004
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    Location: Queensland, Australia

    mojounwin Junior Member

    I've been trying to find info about sk90 for use in rigging, but the websites selling it seem to only suggest it for running rigging or other things. Would ove to hear anyones experience with it.

    Cheers
    Mojo
     
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