Index

Life Lines - Vinyl Coated SS Wire Versus Dyneema.
INDEX - Catalina, Panache

CORROSION - The problem with vinyl coated SS wire is there is no way to gauge the quality or strength of the wire after the vinyl has cracked.  Over the years the water intrusion will lead to corrosion.  Consider that it took 30-40 years for industry and race committees to come to this conclusion.  Their realization happened after several crew members each broke through their life line and died during various ocean races in the 2020s.  As a result many ocean race committees now consider vinyl coated SS wire unsafe and no longer allow it. 

At a glance a person might judge the aging lifeline to be strong enough to keep them on deck, but a closer inspection will likely reveal many flaws.  Granted a crew on a fresh water SJ23 is more likely to trip over a low lifeline than to break it but you should heed the advice of these committees.  Just like the service life of standing rigging in the southern US is ~10 years, so should a life line have a shorter life.  Panache's 40 year old life lines in Canada had many cracks and were therefore due for replacement.  Corrosion just takes longer in the north.  Ah the impressions of guestimating (my SWAG).
- Dyneema does not corrode but has a definitive life when exposed to UV light.  But it is a lot stronger and softer than SS making it ideal for a lifeline.

WEAR - Then there is the wear of vinyl coated SS wire passing through the 3/8" hole in each stanchion.  The wear looks ugly and the exposed wire has a nasty habit of snagging things.  The vinyl coating and then the SS wire will wear at each post, especially if the line is left drooping so it can swing sideways with the hull.  A lifeline should be tensioned to just snug, no more and no less.  Hopefully the tube through the stanchion is smooth with slightly rounded corners at the ends, but don't count on it.
- Dyneema must be protected against chafe where it goes through a stanchion.  This can take the form of lacing twine, a vinyl tube, or any other tough but smooth material.

AVAILABILITY - There are fewer companies manufacturing vinyl coated SS wire these days due to the lower demand and liability issues associated with corrosion. 
   SS Wire - It is fair to mention that it is perfectly legit to replace the vinyl coated wire with bare stainless steel wire.  Its just that the bare wire is thinner and therefore more likely to cut.  Hopefully it doesn't create a meat hook for you!
   Dyneema - Today there is a suitable replacement in the form of Dyneema line.  6MM (1/4") Dyneema is perfect for an SJ23 and is available at most any chandler.  It is slightly thicker than the factory SS wire and far exceeds the strength.  The thicker Dyneema is softer and slightly easier to rest against. 

SAFETY - It has been stated that a safety advantage for a Dyneema lifeline is the ability to cut it with a sharp knife.  (That better be an extremely sharp knife).  The idea being that opening the fore deck lifeline makes it easier to pull a casualty onboard with the line out of the way.  It is next to impossible to pull a casualty through the 16" gap below the line.
- For the 3 times I have extracted a casualty from the water, it was always done this into the cockpit where the freeboard is lower and I can kneel closer to the water.  All things to consider since I usually sail Panache solo.

   Lifeline Net - On Panache the bow portion of the lifeline is blocked permanently with a criss-cross of lines to keep a jib on deck.  Lots of SJ23s are configured with netting like this.  There is no way I can lower the forward line nor could I pull a person on board there.  That leaves a cockpit gate as the only place to pull a casualty onboard.  The freeboard is lower and I'd be more stable kneeling on the cockpit seat to pull the heavy casualty on board.  There is a lot to be said for this. 
   Factory Configuration - The factory SJ23 life line configuration must be released with the single pelican hook at the transom.  The entire lifeline would go slack as it droops lower.  Doing so is handy only if there is an extra crew in the cockpit.  Without that cockpit crew it is an instant justification to install a Dyneema lifeline that can be cut, albeit with a sharp knife.
   Comfort - 1/4" SS lifeline is painful to lean against for any length of time, less so with thicker Dyneema that can flatten somewhat with body pressure.  However, even with Dyneema I wouldn't go without my tube cushions padding the cockpit gate lines.
   Jib Chafe - Dyneema is easier against the foot of the jib when sailing close hauled. 
   Flex - Dyneema can fold easily when the tension is released.  This makes it easier to tuck out of the way during winter layup where it must go straight up/down a stanchion so the winter cover can pack tight against the fixed stanchion and toe rail.  It also makes it easier to clear the deck when a cockpit side gate is open.  While I usually keep Panache's transom gate open, with Dyneema the pelican hook is clipped to the pushpit, leaving the soft line hanging below it.  This takes less room and prevents gel coat damage.
   Strength - The Dyneema line will never break with full body weight flung against it.  It is far more likely that the SJ23 stanchions will give.  Just don't make it a practice to rely on a lifeline to keep yourself on board.  So far this author has managed to stay dry, but I've come close! 
   Safety - In thinking about lifelines on a pocket cruiser, the real strength comes from being attached at the ends; pulpit and pushpit/cockpit post.  The stanchions between just keep the line from drooping.  The short angle bracing at the bottom of a stanchion serves to offset the strain of being pulled inboard due to hull curvature. 
- There is no way the stanchions can stop you from going overboard.  That's my theory and I'm sticking to it.

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FABRICATION - It is surprising how much line a locking Brummel eye splice takes.  You discover this after you spliced the second eye and realize how much shorter it is than the length you cut.  Some of the length can be recovered by stretching the line to remove the construction slack.  After that the line length stays at the stretched length.  Remember to account for this "shrinkage" when determining the location of the splice at the other end of the line.  Failing that you may end up having to redo the splice a tad further down the line, which can best be done prior to tucking in the taper.  It helps to have a good pusher fid.  Fortunately I had enough extra tapered line tucked inside.  Tucking the line inside definitely shortens the line >1-2".  Remember to account for this.
   Thimble - Do include a SS thimble inside the eye as the larger radius maintains considerable strength.  Add a whipping over the thimble to keep it in place.
   Taper - Remember to leave a long length of tapered line tucked inside.  It maintains considerable strength.
   Locking splice, single braid for the free end - https://www.youtube.com/watch?v=d0B6tYTVHVM
   Locking splice, single braid for one end fixed - https://www.youtube.com/watch?v=4WW7Qvg3VjI

I started fabricating the new Dyneema lifelines for Panache incorporating some ideas from a friend's Catalina 27 shown below.  After our discussion he was concerned enough to start replacement the next day.  His conversion included some of his existing hardware to make the transition easier.  My results for Panache are shown below.
 

CONVERSION TO DYNEEMA on a CATALINA 27.

Fig 1, Cockpit Gate - The lifeline gate stanchion at the front of the cockpit.  This stanchion is equipped with the all important SS tube through which the life line passes.  It protects the lifeline from chafe.  To add further protection we opted to add whipping line over the Dyneema.  Note the SS thimble to prevent the line from slipping through the stanchion and to attach the gate line to.  The gate will be converted to Dyneema over winter.

Fig 2, Mid Stanchion - This middle stanchion is also equipped with the all important SS tubing to minimize chafe.  The Dyneema is double protected with none waxed whipping line that slides easier, leading to less chafe.

Fig 3, Pulpit - At the bow the owner opted to terminate the line with a spliced eye with SS thimble terminated by lashing to the pulpit instead of the previous turnbuckle.  For comparison you can see the original SS line on the port side.  The knot makes for convenient fabrication since the length is no longer critical. The lifeline of this Catalina doesn't come down for winter storage.  But if it had to, it would only require releasing the lashing.  On Panache I will also release the lashing since the lifeline must come down for the winter storage cover.

If Dyneema isn't your cup of tea you could install solid stainless steel railing.  Now that is something to experience.
 

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