Islander 36 Conversion: Backstay Fabrication

The backstay was the first stay that I fabricated for the Islander 36. The owner wanted to reuse his older turnbuckles but the cost to replace the swaged top to a toggle and replace the corroded lower toggle with a new one was astronomical! Each component cost around $250, and we need 16, adding a little more than $4,000 to the cost of re-rigging. As you can imagine the decision was made to not repair the old turnbuckles and instead go with deadeyes for the shrouds.

The backstay currently has a new Hayn turnbuckle which we shall be reusing. Since we can retain the turnbuckle for the backstay, we won't need to create a backstay adjuster for minor adjustments before going sailing.

The backstay is responsible for controlling headstay tension while sailing. As a result, the tension in the backstay is often adjusted. Having to rig up the deadeye tensioning system every time you wanted to add tension or ease it a bit would be quite tedious. Retaining the turnbuckle will allow the owner to quickly increase or decrease tension in the backstay with only a few simple tools. 

Since the majority of the work will be performed by the turnbuckle, we don't need an extensive pulley system for the lashings. The lashings will connect the backstay to the deadeye which is attached to the turnbuckle. To add tension, simply loosen the turnbuckle all the way, tighten the lashings by hand and tie them off, then tighten the turnbuckle. If the turnbuckle becomes two-blocked, simply repeat the process. 

Thanks to the mechanical advantage of the inclined plane in a turnbuckle (the screws), tension can be added to the backstay without relying on a complex pulley system.

The deadeye was made using a dyneema grommet with a flat seizing knot tied in the middle. This will hold the thimbles in place for the life of the deadeye and provide a proper turning block for the lashings. 

The backstay was cut to length and then spliced together using mobius brummel eye splices. The length was cut before the splices were put in, as the stay will shrink during the splicing process. As the weave is opened up to bury the tail, the stay will contract. Once the stay is loaded, this contraction will be removed in the form of constructional stretch. If you splice one end of the stay and then mark and measure the other end, you will end up with a stay that is a few inches longer than expected. By measuring everything first, you can properly estimate the final length of the stay after all the constructional stretch and initial creep is removed.

The 12 strands were selected and removed from the tail at regular intervals. I needed to bury 20 inches of tail, but decided to bury 36 inches, as the extra bury is extra security. Should a splice in the backstay fail, the mast will come crashing forward! These extra inches are simply added security for the stays structural integrity.

The additional bury allows for a full 20 inches of bury at the ropes original size and weave. The last 16 inches were thinned at regular intervals producing a very sleek and smooth taper. If the tail were to end in a blunt cut, the splice would hold with plenty of strength but the stay would fail prematurely. The sharp transition from buried tail to no buried tail would become a source of stress on the stays fibers which would become the point of future failure. By tapering the stay slowly and gradually, this source of stress is eliminated and will prevent any premature failure of the stay. 

Once these pieces of the tail are pulled out of the weave and cut off, this part of the tail can be milked back into the stay. With the thimble in place, the stay is now completed and ready to be installed on the yacht as the new backstay.

Turnbuckle or Deadeye

When you re-rig your yacht with synthetic standing rigging, you need to ask yourself if you want to keep your turnbuckles or not?

This question is ultimately up to the owner to decide. Each has their pros and cons, and you need to be willing to accept the limitations of each.

Turnbuckles are the standard method for tensioning standing rigging. Turnbuckles hold two screws, one has Left Handed threads, the other Right Handed threads. As you turn the turnbuckle, the threads will simultaneously pull in or push out. When they pull in, they will make the stay shorter and add tension in the process.

The reason turnbuckles work so well is thanks to the mechanical advantage they offer. Turnbuckles use a few simple machines to achieve their purposes, first is the inclined plane. The threads on the screw are actually an inclined plane, and as you turn the turnbuckle, you are moving along that incline. If your turnbuckle screws are 20 threads per inch, that means that 20 rotations will advance the screw 1 inch.

The turnbuckle also gets to take advantage of leverage in the form of a wrench or rod that can be used to manipulate the turnbuckle. The leverage gained by the rod multiplies the mechanical advantage of the incline plane in the screws, allowing the turnbuckle to tension the standing rigging to extraordinary levels!

Lastly, turnbuckles are compact. All this mechanical advantage is packed into a small machine which lives just above the chainplate. They are quick and easy to use and hold securely. As you can imagine, such a strong and powerful machine would have an equally qualified price to match, and they do. Turnbuckles are on the expensive side, and have a recommended service life of 10 years. After 10 years, they should be replaced, and the cost of doing so can be rather impacting. The minimum number of turnbuckles on a single spreader sloop rig is 8:

1. Headstay
2. Backstay
3. Port Cap Shroud
4. Starboard Cap Shroud
5. Port Forward Lower Shroud
6. Port Aft Lower Shroud
7. Starboard Forward Lower Shroud
8. Starboard Aft Lower Shroud

Additional stays from a second spreader, split backstay, or cutter rig will add turnbuckles and cost to the equation. When I re-rigged Wisdom, we had 11 stays to replace. The total cost for the materials (including extra line for spare stays) was $4,400. 11 turnbuckles would have added $1,100 to the cost, making the process of re-rigging much more expensive!

What could go wrong with a simple turnbuckle? A few things actually. Turnbuckles are typically made of stainless steel and bronze. The bronze components will last a very long time and show little damage from corrosion and stress. The stainless steel components will suffer from corrosion, both external and crevice. Crevice corrosion will lead to catastrophic failures with very little warning. While most of the turnbuckle can be inspected with ease, the section of threads inside the turnbuckle will prove very difficult to inspect. Yearly disassembly and inspection is recommended to evaluate for crevice corrosion, which then necessitates a yearly re-tune of the standing rigging. 

Turnbuckles offer a quick and easy way to tune your rigging with a few simple tools and a basic knowledge of rig tuning. Their only trade-offs are their ability to corrode and price.

The alternative to turnbuckles are deadeyes. Deadeyes use lashings to form a block and tackle setup at the bottom of the stay to achieve the necessary tension needed to tune the rigging. Deadeyes consume 4 feet of dyneema, making them rather economical by comparison. For example, a small deadeye made of 3mm dyneema would cost $6.40, while a large deadeye made of 9mm dyneema would cost $24.20; significantly cheaper than a turnbuckle.

As always, there is a trade-off. Deadeyes are much more time consuming and complicated to adjust when compared to turnbuckles. A small boat with turnbuckle rigging can be tuned in around 20 minutes, and under an hour for a mid-sized yacht. Deadeyes take nearly 20 minutes per stay and require advanced knowledge of knots and pulley systems.

While deadeyes may seem complicated and time consuming to adjust, they are not that bad. Standing rigging doesn't need to be adjusted all the time. I recommend a spring time tune up, which is a one time thing for the year, and not such an ordeal when lumped in with all the other spring time commissioning rituals.

Being how deadeyes are made of synthetic fibers, they will not suffer from corrosion of any kind. They are also very easy to inspect visually as any damage that occurs would occur on the surface of the rope and will be easily seen upon closer investigation. Pretty much, slight fuzziness is to be expected as the outer fibers degrade from UV exposure while the inner fibers remain unharmed; serious chafe will cause serious wear on the deadeye. If the chafe is severe, the dyneema grommet can always be replaced.

Deadeyes offer an inexpensive method to tension your standing rigging without any concerns of corrosion, but at the cost of more time consumed in tuning of the rigging. Turnbuckles offer quick and easy rigging adjustments but at a higher cost and with the risk of corrosion leading to failure.

Climbing a mast in the heat

Safety must be the top priority when climbing the mast. On hot and sunny days, extra care must be taken while up there as the sun will fiercely beat down on you, causing all sorts of heat related problems. Climbing the mast is strenuous on its own, adding intense heat and sun to the mixture only compounds the difficulty.

One of the problems that can happen while aloft is passing out from heat exhaustion. If you pass out and are climbing the mast alone, you might be hanging there for quite some time which could pose a great threat to your life. Preparation is the key to safely climbing the mast in the heat of the day.

When you go up the mast, your entire world becomes restricted to what you have with you. If you are hungry and there is food in the galley, you have no food! You need to plan ahead and take everything you might need with you in your canvas bag: tools, lines, food, water, and anything else you might need.

Food is important to carry up with you as your blood sugar can drop from all of the effort involved in climbing. I like to carry honey nut snacks, as they give me a boost of sugars as well as protein to help fight off hunger. They are also bite size and won't get your hands dirty. This means that you can easily reach into the bag, grab a few, and eat them while you work aloft.

Staying hydrated is very important while up the mast. I carry 1L of water per hour I plan to be aloft, as well as an additional 250mL bottle, just in case I end up staying up there for longer than I intend. If I plan to be up there for an hour, I'll carry 5 bottles of water, and typically consume them all before I get back on the deck.

Another crucial component in the equation is clothing. You need to dress in clothes that will both keep you cool and protect you from the sun. I wear cotton shirts and pajama pants when going up. The light fabric keeps me cool while the long sleeves and pants keep the sun off of my limbs. They also protect me from the heat of the spars that have been roasting all day in the sun! A straw hat will keep the sun off your head and still allow air to flow through, keeping your head cooler than if you were exposed to the sun. Lastly, wear some good sunglasses; everything is white and the sun will be glaring into your eyes while you try to work. 

If you have to be hot, sweaty, and baking in the sun, at least be as comfortable as you can with plenty of water, snacks, and shades.

Going Up!

Mast climbing should be carefully performed with an utmost emphasis on safety! Each component of your gear should be looked over with scrutiny to make sure everything is in perfect working order. If anything is questionable, don't hang your life on it.

While climbing the mast on the Islander 36 that I am converting to synthetic standing rigging, I noticed that the main halyard is not properly spliced. Instead, the halyard is looped back and stitched together with whipping twine. I was not about to hang my entire life on a questionable halyard termination, so instead I eliminated the weak link from the equation. 

I removed the shackle from the halyard and tied the whole halyard through the gantline block with a secure bowline. This will ensure that the strength of the connection is as strong as a good condition New England Ropes Sta-Set rope, rather than as strong as a whipping twine.

Once back on the deck, the halyard was untied and the shackle replaced into the halyard. This way, nothing was altered on the clients yacht and my personal safety was never hanging by a whipping twine. 

Going up a mast carries inherent risks, most due to falling. By carefully inspecting every part of your gear before you climb, you can make the climb and controlled descent as safe as possible. Be sure to inspect everything each time, as your own gear will break down over time and catching any weak links early is critical to your longevity.

Dyneema Grommets Looped Together to Form a Chain

I was recently asked if the grommets could be tied in an interlocking fashion as to create a chain of dyneema links using my method of making a dyneema grommet.
The answer to this question is an obvious yes, each grommet simply needs to be spliced together with the previous grommet inside the loop.  

I had actually made a set of three links while I was still practicing the art of making grommets to use as deadeyes. I made three links to quickly and easily evaluate the interaction between two pieces of dyneema under a load. 

The three links provided me with a wealth of information about how dyneema interacts with loads placed upon it and how it interacts with other dyneema rope under a similar load. It also helped me evaluate the best position to locate the splice on the loop. The top link has the splice in the bottom at the connection to the middle link. The middle link has the splice in the middle. The bottom link has the splice located inside the thimble.

This information led to my decision on using thimbles in my deadeyes and to position the splice in the middle of the deadeye. The top link was hooked over a pipe on a scaffold where the middle link connected the system to the bottom link which had a weight hanging from it. I didn't take any pictures of this test because I didn't have a website or any plans on doing rigging commercially at that time. I was merely designing and testing methods to re-rig my own yacht which led me to produce the current system that I have and use.

The results of the test can still be seen in the loops though. The top link (left link in the photos) was hooked over the scaffold and still retains the bend that it picked up while under the load. The bottom link had a thimble in the bottom portion to hold the weight. The middle link was left untouched to evaluate how the different connections interact.

The top link that was hooked over the pipe was fine, indicating to me that if the object I am attaching to is large enough, the grommet can simply loop over it without any other form of connector.

The junction of the top link to the middle link also tested the durability of the splice when under direct contact by other ropes. The splice held up fine, even though the middle link formed a tight radius bend over the splice.

The middle link was the most interesting to observe. It has tight radius bends at either end and the splice located in the middle of the link. The splice side and the bury side both shared the loads equally and evenly. The splice was also easier to inspect which became my preferred position to locate the splice for the deadeyes. The ends of the middle link did suffer from being bent over the tight radius turns of the other links, which could lead to reduced longevity of the grommet. The deadeyes for the standing rigging should not be subjected to such tight radius turns as it could lead to premature failure of the dyneema.

The connection of the middle link to the bottom link is different from the connection at the other side of the middle link, where a splice was involved. This connection was simply two pieces of dyneema bending over each other. They seemed to hold up well, but did form a rather tight radius bend, which is not the best for longevity of the dyneema.

The end of the bottom link was subjected to loads with a thimble placed in it. The splice was also located at the bottom, inside the thimble. The splice held find under load and with a large radius turn, as guided by the thimble used. This seemed to be the preferred way to connect the standing rigging to the deadeyes, as the thimbles will force the grommet to retain a properly radiused turn while under tremendous loads. The splice located at the bottom worked well but was difficult to inspect.

After being loaded, the links retained the shapes they became during the test. The top and bottom links had ends that were forced to maintain large radius bends due to the scaffold pipe on the top link and the thimble on the bottom link. The ends that were not guided formed much tighter radius turns, as they folded over each other. While the bend was rather tight, the loads were maintained even on the links, and none of them showed any signs of problems. The splices also functioned well in all three locations: In the connection, in the middle, in the thimble; and the location for them to be in the middle on my deadeyes was purely for inspection purposes.

Based on this experiment, I decided to manufacture the deadeyes with thimbles on their ends and the splices located in the middle of the grommet. The thimbles provide a properly radiused bend even when under the immense load of working standing rigging.