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Installing the New Rigging – the Final (?) Chapter

Current Location: Mar Menor, Spain
Current Position: 37 44.25 N 000 44.78 W Click to view map.
Distance sailed since last post: 2278 nautical miles. View the map of our voyage track here

This story, you will remember, started in Gibraltar in October, when we first installed the new upper diamonds. But we didn’t receive the other pieces as John from Colligo Marine didn’t have them in stock. So he sent them to us in Canada instead, and we brought them with us. Only to find that two of them were totally the wrong length, and one was marginally too long. So John had to send us replacements for the two wrong ones.

Which then got stuck in customs.

Finally we got the bits out of customs, though it took a week and cost 70 euros.

We now had the new inner diamonds (the correct length, after John’s measurement screw up) and some fittings for lashing the lower shrouds which were too short (that was my measurement screw up). I put up the inner diamonds. They fit perfectly.

However, I noticed that the outer diamonds had stretched. The mast bend had gone. Since they were already at the end of the turnbuckles,  I took them down and re-did the splice, shortening it by about 4 inches. I put them up again and they just reached the turnbuckle, and I was then able to tighten them down to mid point.

For the lower shrouds I decided to put the lashing at the top end, so that it would be out of our way as we walk along the side of the boat. To do that I used the flat plates that John had supplied for the uppers (which I then replaced with the longer Gibraltar ones). I put the plate into the t-fitting bracket. The other end of the plate went into the new lashing terminal John sent me (to go on the chainplate). Then comes the lashing and finally the terminator on the Dynex. The bottom end of the shroud went into the turnbuckle as before.  However, I had apparently lashed it a bit tight, so it barely made it into the turnbuckle, and could only be tightened up a very little.

It was tricky doing up the lashing halfway up the mast. But all went well. Everything was tightened up and seemed ready to go.

New Dynex Dux lower shrouds with the lashing at the upper end (just below the spreaders)

We then went for a sail upwind in 25kts.

And discovered that the shrouds upper and lowers were way too loose. But now we had run out of space on the turnbuckle for the uppers.

So I went up the mast again, took off the new Gibraltar plates and replaced them with the originals, putting the Gib plates at the top of the lowers (which then had to be re-lashed).  I was a bit concerned that I wouldn’t get the uppers back into the turnbuckles, but I rigged the main halyard to the end of the boom and cranked down on the mainsheet. That put enough tension on the mast to get the turnbuckles on.

The uppers were now super tight, ,the lowers also quite tight (not enough turnbuckle space to loosen them). But the mast bend had gone again.

We sailed around to Mar Menor in 20kts upwind. Also got a reply from the sailmaker who said we need about 10-13cm of mast bend.

So, we definitely needed more mast bend and also need to be able to loosen the lowers a bit as there is no room in the turnbuckle to let them out further. The mast bend is induced by the diamonds (as well as the mainsheet and general downward compression from the uppers) and it is inhibited by the lowers.

So, up the mast again. Re-did the lashing, letting out about 16 inches of line to lengthen the stay by about 2 inches, which was just perfect in the turnbuckle – though no doubt it will stretch a bit again as the lashing settles down.

The outer diamond seemed to be loose again, which is why the mast bend had gone. I guess the construction stretch in my new splice was still working out. So I tightened them again today, and also put a few more turns in the inner diamonds.

So now we have the mast bend back again. The lowers are a bit looser, and the uppers are still tight, though not as tight as they were two days ago.  Which also means the forestay isn’t as tight either.  Tricky to know where to set it, as I don’t want too much strain on the boat, but also I want a nice tight forestay. Guess I will have to rely on the mainsheet for additional forestay tension.

The mast is in column, and is dead centered – well, maybe canting 1/4 inch to starboard.  Mast rake is set by the forestay, so can’t adjust that.

Have yet to go for a sail with this new set up. I expect to have to tighten the lowers a bit, as the new lashing relaxes, but the rest should be good to go, I hope.

One thing that is new though, is that we are now getting harmonic humming from the shrouds as the wind blows through them. Haven’t had that before. It only started a couple of days ago when we tightened everything up.  Gets quite loud at times. I put some elastic between the lowers and uppers to try to add some dampening. It works to some extent, but still we get some hum, which is rather annoying. And even the split pins rattle in their holes!

Something is a-humming in the new Dynex Dux shrouds

So there is the saga. I must say that being able to adjust the lashing as well as the turnbuckle provides a lot of flexibility in getting the settings right. I was also surprised at how tight I could get the lashing. I did it with the turnbuckles just screwed in. I put my whole suspended weight on the lashing string (remember, I was in my harness) , and it held pretty well when I took my weight off, so when I had done up the lashing we could only tighten the turnbuckle by another inch. Barely enough for the screw threads to show, which is why ultimately I had to relax the lashing.

5 Responses to “Installing the New Rigging – the Final (?) Chapter”

  • Heidi Swanson:

    Didn’t understand a word of that, but got a good picture of you up the mast.

  • David Cherry:

    Thanks for publishing your experiences with Dynex Dux.

    I am expecting to do the same for my Catana 40 (1988) cat. Do you have any more observations/recommendations/experiences with your set-up?

    • noel:

      Hi we are now several years down the road with the Dynex Dux, and I am still very happy with it. Not much to add really. The only tricky part is getting the measurements and length right – plus the fact that the splice may relax between them sending it and you receiving it, which is what made our installation tricky. Having said that, I actually redid the splices on one of the stays (can’t remember which) – it is very easy to do. So another option is to just buy the bits and do the splicing yourself. Maybe get some smaller diameter Dyneema and practice a few splices – or make yourself some soft shackles. (see here.

  • Hi Noel, I have found all this very interesting. We are re-rigging our Switch 51 with Dynex Dux. Can you give some insight into how often, and how, you retighten your rig?
    Thanks

    • Noel:

      Hi Peter,

      We are now four years into the Dyneema Dux and have no complaints about it yet.

      Since we are in the Med and have to leave the boat for several months what I have actually been doing is to slack off the tension while I am away. I figured that would reduce some of the creep. Then I just do it back up again when I get back. I am still sort of playing with the fine tuning of it all, so can’t really give you a definitive answer on your question. However, I don’t think it is a major issue, as the rig tensioning is more of an art than a science, and is far from exact. So when you are sailing in a blow just check your tension and if it looks like it is getting a bit slack, then do it up some more – but that will probably be only every couple of years or so.

      Hope that helps somewhat!

      Fair winds,
      Noel

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