Dynex Dux for lifelines (and standing rigging)

[Zanshin]

Two days ago I toured a Catana 58 and, apart from the size and configuration of the massive boat, was very impressed with their new standing rigging and lifelines made out of high-tech line.

My lifelines are standard 1x19 strand but unfortunately covered wire which is already staining a bit and I've already debated replacing it with uncovered wire. But the Dynex Dux material is stronger and simpler to install and weighs less (plus it is now approved by the ISAF Offshore racing rules, which gives it some legitimacy in my eyes) so I am seriously contemplating making the switch.

The other standing rigging on the big Catana was also replaced with Dynex and looked very impressive, but I am not quite ready to go that far. For a boat that size the weight savings were high, but for a cat the lower weight plays more of a role than in my monohull.

Has anyone here switched from wire lifelines and is willing to comment on their experiences?

[zz4gta]

I made the change. Didn't have the balls to change out the standing rigging 2 years ago, so I'm slowly changing that w/ new stainless.

The lifelines were dirt cheap. Fittings? There are none. It took me maybe 30 minutes to measure, cut, and splice the ends on. No chafe yet after one season, but not a lot of hard hiking either.

I could change out lifelines w/ hi-tech line 3 or 4 times before I could justify spending the money on stainless. I went with 1/4" and brummel splices. Best to put a lashing at the cockpit end to adjust sag if you race.

[Zanshin]

zz4 - I didn't realize that, for lifelines, the dynex dux was cheaper than stainless; I've been working on the assumption that it would cost more. I suppose that not having to use fittings is the big cost advantage.

Right now what is keeping me from even thinking about replacing the standing rigging is that the projected lifespan for this new material is about 5 years as opposed to stainless steel's 8 years. I'll wait another year or three and see if ISAF or RORC make recommendations. I suppose it will be an extension of the life cycle, just as what happened to fiberglass airframes with gliders - started off with 500 hours, then 1000 then 2000 then unlimited.

The modified brummel splice recommended by Caligo Marine at http://www.colligomarine.com/docs/mi...eb_rev_1_2.pdf looks pretty straightforward and simple to implement. Did you find it easy to do?

[flatracker]

What size Dynex was used for the rigging. Is it the same size as would be used with stainless, or is it bigger.

[Zanshin]

I think that the same size was used for the lifelines on the Catana and somewhat smaller on the shrouds - but at that dimension the permissable loads were higher and the stretch and creep smaller than the original steel.
The shrouds on the Catana had a bit of chafe where the dyneema genoa lines rubbed against them, but it was hardly noticeable and the lines were already one year old and had a lot of bluewater miles on them.
I've searched the internet a bit on this fiber and am surprised that it is being used for trawling lines from 2km to 10km long! With little stretch they won't hold energy and whip back like wire will.

[zz4gta]

I used Dyneema for mine, not sure if that will make a difference in price for you. Also went larger w/ 1/4" for comfort, but was still cheaper. Got it through Defender.

The Splicing is pretty easy, just practice the day before and you'll be golden. Remember though, using the brummel splice you can only luggage tag one end to attach it directly to the railing. The other end will need a lashing or alternative splice. Eye splice w/ lock stitching and whipping always looks nice.

[tommays]

ISAF Offshore Special Regulations 2010 - 2011

3.14.6 Lifeline Minimum Diameters, Required Materials, Specifications
a) Lifelines shall be of :
- stranded stainless steel wire or
- single-braided Dyneema® rope

Question:

Does the term “wire” in RRS 49.2 include Dyneema® ropes as defined by OSR 3.14.6
a)?

Answer:

No. Rope of any description can not be considered as wire. Boats wishing to use the
provisions of the second sentence of rule 49.2 will need to continue to be equipped
with upper and lower lifelines of wire unless rule 49.2 has been changed by the sailing
instructions or class rules to allow the use of other materials.

THATS REAL CLEAR

[A320G4]

I"ll be replacing my upper and lower cap shrouds with Dux from Calligo this off season on my Contour 34 Tri. I think Dux has a higher safety factor then wire.

Colligo does make fittings for lifelines, have a look on there web site. The Dux is sensitive bending radius, that's why the terminator are sized to the dimension of the line.

[Paul_L]

Why use Dynex Dux over just Amsteel (Dyneema)? It is more expensive and its advantages, such as less creep, are not needed in lifelines. Dux is great for stays, but the extra cost is not needed for lifelines.

Paul L

[RobertKWFL]

I just finished installing 1/4" Amsteel Blue lifelines using the CS Johnson line of lifeline hardware made for synthetic rope. The splices (eye with lock stitching) were very easy. I went this route because I don't like how plastic coated wire promotes and conceals corrosion, and I don't like the hard look and feel of uncoated wire. The dyneema lines are lightweight and comfortable. It's easy to keep extra rope on board in case you ever need to do an emergency repair/replacement.