Synthetic Rigging Conversion

While I was on the hard, Tim Wolbert aboard Marialo was getting his rigging replaced with new stainless steel 1x19. Replacing my standing rigging was on my list of things to do, and watching his be replaced made me take a close look at my own standing rigging.

I had replaced my running rigging the previous year when I had my new sails made and knew that the standing rigging would be next before any ocean sailing were to occur. When I took a good look, it was startling to see what I had been trusting my mast to, many of the stays had corroded wires that ran up the stay creating dark streaks that circle up the stay making it look like a candy cane. 

The backstay has corroded strands

The backstay has corroded strands

This along with the corroded fittings pushed the standing rigging to the top of my to-do list. 

I began looking for alternatives to stainless 1x19 since I plan on doing ocean sailing and the salt will destroy any metal. I considered using galvanized 1x7 steel that had been wormed, parceled, and served; as this would keep out any salt, water, or anything. Galvanized steel is a bit stronger than stainless, but it can be preserved in this wrapping. The downside is that the covering needs to be frequently painted with slurry to keep it water tight. If there is any lapse in maintenance, corrosion can quickly start and since it's covered, there is no way to easily inspect it. So... strike that idea.

I began looking at other materials and stumbled across synthetic fibers. Dyneema is stronger than steel and a fraction of the weight. The problem with synthetic fibers is creep. As a dentist, I deal with creep in various materials and know how to factor it in when designing a system.

I was all excited to talk to Colligo Marine at the Annapolis Boat Show later that year. The idea of an entirely synthetic system was music to my ears. No longer having to worry about corrosion in turnbuckles or inside compression fittings at the line terminators was the peace of mind I wanted to have when I set off on an ocean voyage!

My conversation with Colligo was very disappointing, I was told that no boat over 25 feet could be rigged with deadeyes and that it would be impossible to rig a 45 foot because I wouldn't be able to get the proper tension in the rig.

This is when I began my study into rigging, going all the way back to Viking and Egyptian rigging and working my way towards modern stainless steel rigging. Throughout history, rope was used as standing rigging, tensioned with deadeyes and lashings. The concept of steel and turnbuckles is a very recent blip on the rigging history. For a long time, hemp was used as the standing rigging on tall ships. If they could rig the tall ships that way, there is no reason that modern fibers can't rig a 45 foot cutter!

Looking at the modern instructions for how to tie off the lashings shows why no one is able to tension synthetic rigging properly. By combining the traditional methods of deadeyes and lashings with the proper traditional knots, it was very easy to tension and tie off the rigging for a 45 foot cutter. This includes dealing with the creep!

Dyneema Deadeye For information on how to make a Dyneema Deadeye, click here.

Dyneema Deadeye

For information on how to make a Dyneema Deadeye, click here.

There is no way to create enough pre-tension by hand with deadeyes, this is a fact; but by using a pulley system, it can easily be achieved. When I tensioned my forestay and shrouds, I constructed a 1200:1 purchase system, making it very easy to achieve the thousands of pounds of tension needed.

The rigging was perfectly tuned with the mast in column and allowed to sit under tension to allow the creep to take place. In a few days, stays that were bar tight were now very slack. Once again, the rigging was tensioned and allowed to creep once more. After about 6 to 8 of these episodes, the rigging was mostly stable as it was nearing the end of the first of the three stages of a Dyneema life cycle. During the first stage, creep is quite extensive as the fibers in the weave are settling in. During the second stage, creep becomes very minimal and the stay will hold its tension very well. During the third (and final) stage, the creep begins again and this is the signal that it's time to replace the stay.

Once the stays settled in, we were able to go sailing every weekend without needing to touch the rigging (which was a nice change after messing with it for over a month). During our later trip into the Atlantic Ocean, I was frequently checking the rigging to make sure the mast was still held straight and true. It was able to make the entire trip without needing to be touched once!

The weight reduction from switching to the lighter synthetic rigging made the boat float higher. This vessel weighs 17 tons and came out of the water a few inches!

The weight reduction from switching to the lighter synthetic rigging made the boat float higher. This vessel weighs 17 tons and came out of the water a few inches!

Another nice feature about the synthetic rigging is the reduced weight aloft which led to less heeling while under sail. We used to sail heeled over 20* in 10 kn of wind, and had to put the first reef in at 17kn, and the second reef at 22kn. The headsail had to be taken in at 15kn as well. The reefs were mandatory at these wind speeds because our heel would exceed 30* if we did not reef in time. 

With the new rigging, we only heal over 10* in 20kn of wind under full sail! The new protocol is Jib, Staysail and Full Main up to 20kn, Staysail and 1 Reef up to 25kn, 2 Reefs at 27kn.

At one point, we were on a beam reach in 27kn of wind and full sail, only healing over 20*! This wind came on all of a sudden and with no warning and was quickly taken in to Staysail and 2 Reefs. It was nice to have the buffer of reduced weight aloft which kept us more upright in the blow.

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