Boatworks

Dynex Dux Across the Atlantic

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On August 23, 2011, our 35-foot Allied Seabreeze yawl Arcturus (vintage 1966) became—we believe—the first monohull to cross an ocean sporting Colligo Dynex Dux synthetic fiber standing rigging. This after a 3,000-mile passage from Annapolis, Maryland, to Crookhaven, Ireland (“A Long Way to Europe,” June 2012). 

The decision to fit the unproven rigging on the boat came after a handful of serendipitous meetings. I first saw Dux at the 2009 Annapolis Sailboat Show as we were just starting in earnest to prepare the boat for the trip. I had already placed an order for some quarter-inch wire, but at the show we discovered an old Westsail 32, which was being re-rigged with Dux shrouds spliced around solid thimbles and tensioned with deadeyes and lashings. The traditional style fit the boat, and I liked what I saw.

I then chatted at length with Mike Meer of Southbound Cruising Services, the brains behind the operation, and John Franta of Colligo Marine, who was also onhand. Brion Toss, one of the foremost experts on traditional and modern rigging, also happened to be there. I was intrigued by the Westsail’s rigging, but I was not swayed until I spoke with Toss. After attending his seminar on rigging, I cornered him. Was this for real, or just a gimmick? His answer—“Wire rope will be a 150-year anomaly in the history of yacht rigging”—convinced me to give Dux a try. 

Redesigning our Rig

After the show, my girlfriend (now wife) Mia and I ordered a spool of Dux from Colligo with the required fittings to replace the rig on our mainmast. En route to Florida down the ICW, I learned to work with it and taught myself how to make a splice so that I could create the thimble terminals on my own. 

Where wire is sized according to its breaking strength—taking into account a boat’s righting moment and the forces exerted on its rig, plus a safety factor—Dux is sized according to how much it creeps. Creep (unlike stretch, which is elastic) refers to the permanent elongation of the plastic fibers under load and over time. Although Dux actually stretches less than wire and its breaking strength at a given diameter is 2 to 5 times greater, it will creep when loaded past a certain percentage of its breaking strength. (For more on the technical aspects of Dynex Dux see “The Return of Rope Rigging,” May 2012.)

To prevent creep, our new shrouds were slighter larger (9mm) than the wire shrouds they replaced (7mm) and thus much, much stronger. A rig is only as strong as its weakest link, and in our case we realized the bolts holding the chainplates to the hull would sheer long before the Dux broke. 

The Seabreeze also has an inherent design flaw in that its chainplates, which are attached to bulkheads and emerge through the deck near the toerail, do not match the shroud angles. Specifically, the fore and aft lower chainplates are aligned vertically, while the shrouds are offset several degrees fore or aft and inboard. This causes undue stress on the chainplates.

To take advantage of the strength of our new shrouds, we therefore mounted new chainplates externally on the hull, added a fourth fastener hole to each one, and upsized the bolts securing them. Now each chainplate on Arcturus is perfectly in line fore and aft with the shrouds and is bent inboard at the toerail to match their athwartships angles. We also strengthened the geometry of the rig, adding a second set of spreaders and an additional intermediate shroud, plus an inner forestay with runners. 

Across the North Atlantic

We left Annapolis on July 4 and headed north for Nova Scotia before turning east toward Ireland. One of the quirks of Dux is that it does not expand and contract at the same rate as aluminum. Therefore, as the weather got colder, we found our mast contracted more quickly than the shrouds, and as a result the rig went slack.

Offshore in the Gulf of Maine, Mia and I attempted to tune the rig one foggy, chilly morning. We now had eight athwartships shrouds supporting our mainmast, plus the backstay and forestay, which is 5/16in wire, to accommodate our hanked-on headsails. The Dux shrouds were tensioned with deadeyes and lashings—standard 1/4in Dyneema line, rove through a 7:1 purchase. After untying all the lashing knots and sweating through tension on all eight shrouds using a halyard winch, then re-tying all the lashings, my hands were wet, cold and raw. In all, it took us two hours to tighten the shrouds, and I swore I would not leave Canada without first installing turnbuckles.

In Lunenburg, I managed to find 1/2in galvanized turnbuckles at a hardware store (which definitely helped Arcturus look more like a workboat). After fitting the new turnbuckles in Baddeck, on the Bras d’or Lakes, and retuning the rig-—this time in a matter of minutes, with greater precision and more pre-tension—I did not have to touch it again all the way across the Pond. 

Which isn’t to say I did not worry about it. We set out on a rare sunny afternoon on July 31, and it took about a week at sea before my anxiety finally dissipated. From St. Pierre it’s 2,000 miles to Ireland, and as I wrote in the log, I never before felt so exposed. Suddenly I found myself lying awake at night. Did I really tighten all those bolts enough? Did I really have the shroud angles worked out? Did I really remember to bend that cotter pin correctly at the masthead? Fortunately, I had.

What about Next Time?

Arcturus has worn her Dux rig now for a little more than two years. We have sailed her close to 5,000 miles with it, both inshore and off, and north of 50 degrees. Would I put Dux on again? Absolutely. Would I do it differently? Absolutely.

The single biggest advantage to Dux is how light it is, although that is not why we chose it. On big boats, removing weight aloft can make an enormous difference. One large schooner I know of, for example, lost close to 600 pounds from her rig when Dux was installed, making the boat’s helm infinitely lighter. On Arcturus, an older, smaller boat designed to sail on her ear, the effect is less noticeable. Nonetheless, she stands up noticeably better in puffs, is more stable once heeled and rarely buries her rail anymore.  

For me the real attraction of Dux is its ease of use and the way it allows us to take full responsibility for our rig. Mia and I do all the work on our boat and have become experts at handling all her systems. With Dux we can now make up new pieces of rigging all on our own with no help from a professional rigger. So it makes sense for us, and for similar-minded sailors. 

For those thinking of making the switch, be aware that there are real differences from wire. You must, for example, guard against chafe. In St. Pierre we used tarred nylon to serve a portion of the outboard upper shrouds, after noticing the lazy sheets were rubbing here. (I had already done the same thing where the shrouds go around the spreader tips.) Next time around, I’ll be sure to do this in the shop. I’ve also noticed some fuzzies on the lower shrouds where the mainsail presses against them while running. Nothing serious, but again, you need to be aware of it. 

Another big difference: each shroud, when spliced around a terminal in the shop, must be re-tensioned to upwards of 2,000 pounds. This is because as the rope is spliced the braid works loose and must be set back up again. Applying this sort of tension is best accomplished with a huge winch mounted on the shop floor. 

In the end, Dux is like anything new. There is a distinct learning curve, and there will be skeptics and believers. For skeptics, a great introduction is to start by replacing your lifelines with Dux. For those with a new wire rig, Dux makes perfect emergency rigging and will not rust in your bilge. For Mia and me, the marlinspike seamanship we learned, the ability to easily repair our rig at sea and the lighter weight all make Dux the right choice. 

And I must admit, it is cool to have been the first to cross an ocean with it. 

Photos by Andy Schell

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