Taking Advantage of Winters Stretch

Dyneema has a negative coefficient of thermal expansion, meaning that it expands as it cools. When you tune your rigging for summer sailing, it will become rediculously slack in the winter. This is known as "Winters Stretch" and can be used to your advantage! 

During the year, thimbles and clevis pins will move and shimmy while you sail. They are under tremendous tension and there is no way possible for you to push them back into place without untying the stay and then retensioning it. You need to untie everything to remove the tension on the stay, but in winter, the tension is removed as the stay elongates temporarily! 

When your rigging goes slack, you are presented with the opportunity of the year to push everything back into place and line it all up perfectly! That thimble that rotated a bit when you set up your rigging can now be spun vertically with ease. That clevis pin that spun around and has the cotter pin upside down can now be rotated to line the cotter pin head up and keep it from falling out. 

All of these little jobs that would take hours to perform and correct in the summer can be accomplished in a few minutes with no tools, all thanks to the chilling effects of winter. 

Synthetic Standing Rigging in the Cold

As the temperatures plummet, we have found ourselves trapped in cooler weather while we dream of warmer sailing. We have a few options ahead of us, one is to re-tension the rigging for the cold weather and sail along as normal; the other is to work with the slack rigging and make our way towards warmth as quickly as we can! 

If we were going to be doing high latitude cruising in the winter, then yes, re-tuning the rigging would be a wise choice to make as it will facilitate safe sailing with sound standing rigging. The thing is, we are heading towards warmer latitudes and if we tighten the rigging, we would immediately need to loosen it again as it would contract in the warmth. 

This leads us to our decision to follow the second option: deal with it. 

While the rigging is slack, the biggest concern comes in the form of shock loads. When you jibe accidentally, the loads are greatly increased because the sails slam from one side to the other and yank the rigging along the way. When the rigging is tight, the transfer of force is rather mundane, but when it is slack, the loads go from non-existent to out-of-this-world in a fraction of a second. This shock load can lead to a lot of gear failure and ruin a cruise! 

Dealing with it is rather simple. First, no accidental jibes. Second, don't fly much sail. The loads come from the sails being flown. If you fly small sails, then you won't be stressing the rigging very much. This means that we reef very early and usually sail under canvassed. Third, pick downwind courses.  

Sailing downwind is a great way to reduce the stress on the rigging. Everything moves along nicely as the backstays take up the majority of the loads. The apparent wind is also greatly reduced and you can sail towards your desitnation even faster than if you were beating with slack rigging. 

Running towards warmer weather will get you there in a short period of time, this means that soon, your rigging will warm up and you can stop worrying about it being slack as it will tighten back up on its own as it warms again. 

Our rigging is tuned for 80F, and works well all the way down to 60F. We have found ourselves lately in temperatures ranging from 40F to 50F, so we can't wait to be in warmer weather once more! 

Anchor Kettle

Anchors need to be pulled laterally along the sea floor to set and hold well on the bottom. This requires considerable weight of the anchor rode to produce the catenary curve within the specified scope.

When using all rope rodes, more scope is needed to achieve the same lateral pull. A common rule of thumb is 5:1 scope for all chain, 7:1 scope for all rope. Since the goal is to have more weight in the system, the idea of adding weight along the rode came to be. This was the birth of the anchor kettle.

An anchor kettle is nothing more than a weight tied into the rope rode. It hangs on the rope and pulls it downward. This in turn causes the rode leading to the anchor to pull at a lower angle and would nessecitate a shorter scope! 

In theory, this works well, but in practice, it leaves much to be desired. 

The first problem with an anchor kettle is that it causes additional wear in the line. When the weather is calm, the kettle will fall to the bottom and the rope that runs between the anchor and kettle will lay on the sea floor and chafe away as it moves around. 

When the wind begins to blow, the yacht will be pushed back and the kettle will begin to do its job. It will hold the line down in the water and keep the rode from it to the anchor at a low angle. The line from it to the boat will proceed up at a steep angle. This is precisely what they sell it to you as, and this is the only time it will work like this. 

When the wind really begins to blow, the rode will become tight and the kettle will be lifted up. All of a sudden, anchoring with a shorter scope becomes a problem as the anchor will not b able to hold as well. The kettle is hanging on the line, but the line is pulled taught as the yacht is pushed back with the surge of the wind and waves. 

In addition to the problem with the scope being too short and the kettle merely hanging lifeless on the rode, you have the issue with the weight of the kettle in the line. When the yacht relaxes, the kettle will sink down a bit. When the yacht is pushed back with a wave, the kettle will be flung upwards and its mass will continue to yank upwards as the rode becomes taught. This upward jerking motion will actually work to unset the anchor and cause it to drag! 

Anchor kettles are a cool concept, but they do not provide the benefits that they claim and actually harm your anchors ability to hold when the weather deteriorates, which is when you need to count on your anchor the most! If you are looking at an anchor kettle to allow you to anchor with all rope rode, consider investing the cost of the rope and kettle into a good chain rode that will provide you with the needed weight and catenary curve to hold well in all conditions. 

Types of Anchor Rope Rodes

When it comes to an all rope rode, there are two good choices and one bad choice. 

The first good choice is three lay nylon rope. This material has about 20% stretch and considerable strength for its size. It is also the cheapest of all the rope options. Being three lay, it is very easy to splice and also very easy to repair. Should a segment become chafed, it can be repaired by performing a mending splice. Should you need to add length to your rode, you can always carry it out by performing a short splice or long splice. The possibilities are endless when working with three lay nylon! 

The disadvantage of three lay nylon is that it is succeptible to chafe and the section of rope that attaches to the shank of the anchor will be the most chafed section of the entire rode. Careful inspection will let you know when it is time to repair this area and prevent the loss of your expensive and precious anchor! 

The second good choice is megaplait nylon rope. This rope is made by weaving many smaller strands of nylon together in a tight and integral pattern. This line is considerably more expensive but at the same time, considerably more resistant to chafe than three lay nylon. It doesn't have as much stretch as three lay, but it is still enough to absorb the shock loads presented by a well buried anchor.  

Splicing megaplait is very tedious, as there are many small strands to deal with and it takes considerable patience to complete a splice. Repairing megaplait is also rather tricky, so it is fair to say that it is not as friendly to the user as three lay is, but still a very good option if you can afford the line. 

The last option, which is the bad option for an anchor rode is any kind of double braid line. Double braid line does have an outer core that would protect the core from chafe, but the core is impossible to inspect from the outside to evaluate its strength and it does not have anywhere near the needed stretch characteristics of regular megaplait or three lay. This means that the shock loads on the rode will be higher, putting the rode at much greater risk to cause damage to the ground tackle system and possibly snap the rode.  

While all rope rodes are an option for an anchor rode, they are far from the ideal setup. The rope is rather light and will not provide the catenary curve needed to create the lateral pull the anchor requires to set and hold properly. All rope rodes require much longer scope to achieve the same holding power and are at risk of chafing through and breaking.  

If you anchor for a few hours on a weekend when the weather is nice, a rope rode will serve you well. if you plan on cruising and spend almost every night on the hook, it will be worth the investment into an all chain rode. 

Types of Chain

In the world of anchor chains, there are a few key players. All of these chains will be labeled with a number or letter stamped into the links metal. If you do not see any markings, the chain could be a cheap knockoff that might not be built to the same rigorous standards. 

Chain also comes in a few materials, mainly consisting of galvanized or stainless steel. We will be focusing on galvanized chain in this post. 

There are three main types of chain: Proof Coil, BBB, and High Tensile strength chain. 

Proof Coil is by far the cheapest and weakest of the chains. The links in this chain are made from carbon steel and covered in a protective galvanized coating to ward off corrosion. Proof coil is identifiable by the markings PC, PC3, G3, or Grade 30. Upon construction, the chain is stressed to its breaking strength and then inspected every 10 links. It is not calibrated to work with the wildcat on windlasses, so it might not be as easy to retrieve as you might have hoped. 

BBB is the next step up. Also made of carbon steel, it is inspected at each and every link upon testing. This means that the chain is strong and checked throughly before it reaches you, the consumer. The links in BBB are uniform and it will work with a wildcat on your windlass! Identifying marks on BBB chain are: BBB, and 3B. It tends to have the same weight per foot as PC chain, but it will work in your windlass and it was inspected more throughly before you bought it. 

Hgh Tensile chain is made from heat treated and high tensile strength carbon-manganese alloy. It is much stronger than regular carbon steel, so a chain of the same strength can be made of much smaller links. This means that the chain will weigh less per foot and will upset your displacement and balance much less when fully loaded.

HT chains are marked as Grade 40, G4, and G43. These are manufactured under the same rigorous testing of BBB chain, but you get a much lighter product with the same strength. Higher strength chain is marked as Grade 70, G70, and G7. This chain is very light and very strong, offering the best strength to weight ratio. This will allow you to carry hundreds of feet of rode in your bow without weighing your bow down into the water. 

While HT chains are favorable with their weight reductions, they do have one draw back over BBB, and that is the heat treatment that gives it strength. When a chain needs to be re-galvanized, the heating of the galvanization can damage the heat treatment of the chain. Grade 40 and 43 chain is more resistant to the process, but Grade 70 is very delicate and can loose its strength by regalvanizing.