Sailfeed
February 23rd

Synthetic Lifelines in the Works

Posted by // February 23, 2013 // COMMENT (0 Comments)

Boats and Gear, People, , ,

Photo Credit: The Rigging Company (http://theriggingco.com)

I spent last weekend at the Miami Boatshow where I got to meet a few of the lovely folks from SAIL, critique my father’s seminars and crash a couple of expensive-looking parties. Oh and I even found time for a quick look around the show. The focus was mainly powerboats and megayachts, with a small ‘Strictly Sail’ satellite where I spent most of my time. While there I had a productive chat with John Franta, owner of Colligo Marine and the guy who did my synthetic rigging. I’ve written about my rig a couple times and though it’s about time for another update that can wait. What I’m interested in at the moment, and was talking to John about, are synthetic lifelines.

    Just before the show I finally managed to track down a length of 1” stainless tubing to make my stanchions with so I started thinking hard about what I want to reeve them with. As usual my aim is a low-cost system which is fairly easy to set up and which I can build and maintain myself. I’m also looking for simplicity in order to reduce both the cost and the number of potential failure points.

Wire?
Or fiber?

    My first big choice was material – 1×19 stainless steel wire or high-tech rope? If you’ve read any of my posts on rigging you’ll know I’m pretty keen on this Dyneema stuff. It’s light and strong, which is nice, but mainly I like its do-it-yourself appeal and traditional simplicity. For lifelines this appeal is obvious- it’s possible to make up a set of rope lifelines with just a few simple static fittings and virtually no tools. Compare this to the assortment of toggles, turnbuckles, and attachment tools needed for wire rope. Fiber rope also feels much nicer on the hands and body than wire, and I can’t wait to see how my boat looks with rope lifelines spliced onto traditional deadeyes! At this point you can probably tell that I barely debated the wire vs. fiber question. It’s not that I’m sure that fiber is a better choice but I think the odds are good that it will be and I’m too curious to pass up a chance to find out. After all, I need something to write about!
    There are, of course, a few downsides. The biggest one is obvious- the lifespan of fiber lifelines is much less than stainless. I’m told that uncoated 316 stainless lifelines ought to hold up for twenty years but between UV and chafe I’ll be pleasantly surprised to get more than five out of fiber. The Dynex Dux that I’m using is supposed to hold up longer than that but with such heavy use as lifelines get I’m not holding my breath.
      Still, five years is a good chunk of time and I expect that by the time I need to replace these new line will last half again as long, and only cost half as much. Cost is in my favor anyway as using fiber will be saving me a fair bit of money, at least in the short term. Dynex Dux costs about the same per foot as stainless steel (5mm Dynex Dux vs. 3/16 SS, Colligo Marine vs. Hamilton Marine) and for my four fiber lifelines I plan to buy exactly two fittings! As for the fears people seem to have about this stuff chafing through or getting cut, I’m not worried. I’ve already been running bronze hanks up and down my forestay for months and I can only see a tiny bit of wear, just enough to tell me that a. this stuff is tough and b. it will be obvious when it needs to be replaced. Time will tell whether my lifelines (and rig) hold up well enough to be truly cost-effective, but I’m certainly not worried about sudden failure.

    Having decided on material I started drawing out my lifeline plans. My intent was to get things down to bare bones and so the first bit to go was the gates. Honestly, I just don’t understand lifeline gates on a small boat. With the braces and fittings involved a dedicated lifeline gate adds cost, complexity, and a fair number of potential failure points and yet it is ultimately unnecessary. Nearly the same effect can be had by simply unhooking one end or other of the lifeline and letting the entire line go slack, which actually gives you a gate anywhere on the boat. This is simpler, safer, and  easier to design. Ok maybe it doesn’t look quite as nice as a dedicated gate and it might take a few more moment of fiddling but this seems a small price to pay for an added measure of safety. Anyway, I very rarely bother opening lifeline gates, especially on a small boat with low freeboard. Instead I’m going to make the lifelines continuous and terminate the starboard side with pelican hooks. For the port side I won’t bother with a ‘gate’ at all. Another advantage of fiber lifelines is that even without the pelican hook it would still only take a moment to untie the lanyard and drop the port lifelines.

Here’s a poor illustration. What, your boat has a mast, and a cabintop? Seems like a lot of extra weight… Anyway, you get the idea. This is a lifeline with a lanyard on each end, slacking the aft lanyard. With a pelican hook opening the lifeline is even simpler.

    Incidentally, for simplicity in my drawings I’ve only put a single lifeline but I will be running double lines for added safety.

     Other than the pelican hooks my lifeline installation will only require a spliced eye or thimble on each end of each line, a total of eight eyes and splices. With two pelican hooks that’s a total of ten bits of hardware for an entire double lifeline setup, and eight of those are just solid pieces. About as simple as you can get.

Here’s how it will work:

    Each line begins with a splice over an eye. This is a critical piece of hardware because these new synthetics require a large bending radius. This eye could be as simple as a stainless thimble or as fancy as the anodized aluminum lifeline deadeyes that Colligo sells. For traditional flair I think I’m going to make my own deadeyes out of a piece of Ironwood that has been kicking around my shop. These will be drilled with three holes and through these holes I’ll reeve a lanyard of Dyneema SK-75 which will be tied to the pulpit. Another advantage of synthetics is that I can tie this lanyard to the main body of the pulpit rather than relying on the small welded eye that lifelines are usually attached to.

Here’s the forward end of the lifeline. There’s a reason my sister is the one who went to art school and not me…

Following this will be the length of Dynex Dux lifeline which I will serve with twine at the points where it goes through a stanchion, to minimize chafe. This serving will be fairly loose as John says that Dynex Dux and other Dyneema lines do not like compression loads.  At the aft end of each lifeline will be another splice over an identical eye which will be again tied with a lanyard. This is the lanyard I will use to tension the line, with the deadeye acting as multi-part tackle. On the port side lifelines I will tie the lashings directly to the stern rail while to starboard I’ll tie them to a pelican hook which will clip to the stern rail. This way I can tension the lifelines from the cockpit and/or release them with the pelican hook. It is an advantage of small boats that the freeboard at the stern is still low enough to easily open the lifelines from a dingy.

The aft end, with pelican hook.

Once everything is in place and spliced it will be merely a question of taking up tension with the lanyard, much as I do with my standing rigging. I will be able to release the starboard side lifelines with the pelican hooks, creating a gate at any point and if I need to I’ll be able to release the port side by untying the lanyard.

That, at least, is the plan. Wish me luck!

This article was syndicated from Safe At Harbour But Meant For The Sea: DIY Sailing with Paul Calder

Leave a Reply