Rig Failure - Perhaps it was rougher than we thought!
Mike and Liz Downing
Tue 29 Oct 2013 09:42
We always check our rigging before going to sea on a long passage. The importance of doing so was brought home to us again this week when Jacaranda, the boat we sailed with from Cocos Keeling, found two shrouds with broken wire strands. For those technical it was the aft lowers; for those not, the rigging is made of 19 strand wire called shrouds and a weak point is where the wire comes out of the fittings (called swages) at either end. So it was time to check our rigging and we were shocked to find broken strands in 3 shrouds. Even worse, it included the strongest, 12mm, lower cap shrouds - both sides (one had 3 broken strands and the other one). The 3rd to go was one of the smaller 8mm intermediates. So we needed to replace the 2 lower cap shrouds and both the intermediates (if one goes the recommendation is that you replace both). Our rigging was completely replaced in 2007, so should have been good for 10 years, even considering the mileage we're doing. We had it professionally checked in Sydney before we left and I checked it in Darwin. Jacaranda's rigging was only 2 years old. Of the dozen or so boats that we've met that have made the crossing, no other has reported rig failure. So is it just a coincidence, or was it the periods of rough weather, that being relatively close, we both sailed through. The seas were very confused at times and big, so when we rolled, it was a significant roll and the forces on the rig must have been huge. However, it's built to stand up to these forces and shouldn't have broken.
Although the wire has 19 strands and only 1 or 3 strands had broken, if one goes today the others could easily go tomorrow, so the recommendations is to replace the shroud as soon as a broken strand is found. Now that's not so easy in Mauritius where they have very few resident yachts. With 12mm wire it's impossible as there is no 12mm wire on the island. Reunion, the French island next door (100 miles to the southwest) has many resident yachts and is well supported with yachting services, but, as we discovered, no 12mm wire. So we were snookered and started thinking how we might support the mast with strong rope (dyneema/spectra). We also thought we should discuss the options with our insurance company, to make sure we would still be insured. Now that was a really good idea. We called them last Wednesday and found that one of their reps was flying to Mauritius on Friday in order to meet yachts taking part in the Oyster Round the World Rally that's due to arrive this week (Oysters being very big and expensive yachts). Within sight of the insurers offices in Plymouth is a yacht rigging shop. So the insurance company made contact with the rigging shop and arrangements were made for me to specify what we needed so the rigging shop could make it up in time for the insurance rep to bring it on Friday, as personal baggage. It sounded too good to be true, but wasn't. We met the plane which arrived at 08.00 on Saturday, brought the rigging back to the boat (having hired a car) and the rigger we had arranged arrived at 13.00 to start fitting it all. It took 5 hours, but by 18.00 we had the faulty shrouds replaced and the rig was ready to go. So just 3 days from the initial call to the insurers - not at all bad! The cost, however, was bad - very close to £2,000 when including the rigger's cost.
The rigger was an interesting guy. We didn't expect to find one here as there are few resident yachts, and certainly not one with good experience. However, we were lucky. He's taken part in several Vendee Globe races (single-handed non-stop round the World race), coming 3rd one year, and Transat races (double handed across the Atlantic) and won. So he certainly knows how to sail and did some good rigging work on other boats. The one slight problem was that he's very French. Not a problem in itself I hasten to add, but he speaks very little English (about as much as I speak French!) which made working as rigger's mate, which I did for 5 hours, a little tricky at times. In addition to rigging he teaches the children here how to sail and also provides routing advice for ocean sailors, amongst other things.
Wires that have snapped where they enter the swage terminal. This is 12mm and, everyone says,
stronger than is needed (most boats of our size would have 10mm wire), so we were very surprised.
To try and ensure the replacement shrouds last longer, we have opted for dyform which is supposed to be 30% stronger than normal rigging wire. It's also 30% more expensive! (Our working forestay and cutter stay are also dyform - 10mm and 8mm.) 12mm dyform should be well over spec. Lets hope it is this time!