Measuring the Stays

When fabricating your synthetic standing rigging, you may wonder what length you should cut your section of rope for the stay. The trick is to measure and mark everything before you begin working the line.

The moment you open the weave to perform a splice, you will lose your ability to estimate the accurate length of the finished stay. The length of the stay needs to take into account the amount of line that will be buried back into the line, as well as the amount of line that will be consumed in passing around the eye, and the length of the stay that will be composed of the lashing and deadeye.

The simple method to calculate this is:

Length of the stay + Perimeter of Thimble + Amount buried - Length of deadeye - Length of lashing

The length of the stay is the distance from the mast tang down to the chain plate.

The perimeter of the thimble is easiest to calculate by wrapping the line around the thimble and measuring the length involved.

The amount buried is 72 times the diameter of the line in millimeters. You will also want to taper the end of the tail that gets buried, so it is wise to give yourself the minimum amount of bury before the taper begins. This will ensure that you are not going to end up with insufficient bury on such an important splice.

The length of the deadeye tends to be around 1 foot.

The length of the lashing is up to you, but I recommend planning it to be around 3 feet. This distance gives you plenty of leeway in case your stay comes out a bit long, and it places the lashing in harms way of the lazy sheet. This means that most of the chafe will occur on a disposable lashing instead of an expensive stay.

Once you have all of these numbers calculated, it is time to mark it on the line before you cut it off the spool. When you mark your points, you can then make sure that everything is correct before you cut the line. If you cut the line too short, you will not be able to make the stay the correct length. If you cut the stay too long, you can always trim it shorter. This is why I like to cut a few extra inches of leeway on each end just in case I find that I need a bit more length.

When you stretch out the line to cut, you will start at the bitter end. For this example, we will do the math using 9mm line.

The first point in will be the tapered length. To taper the end gradually, it is best to do this over 2 feet, where the taper runs 1 strand every few weaves.

The next point to measure is the amount that will be buried. For 9mm line, that would be 9mm x 72 = 648mm or 25.5 inches. After the 2 feet of taper, you then need 25.5 inches of bury. This comes out to be 4 feet, 1.5 inches of tail to be buried on one splice.

At this point, you have the taper and the bury marked on the line. Now you will need to measure and mark the thimble section. Simply place the throat of the thimble at the tail mark and work the line around the thimble, then mark it again. You want to make the eye that goes around the thimble loose that way you can easily replace the thimble if it fails. The looseness of the eye can be closed by a small seizing knot to hold everything in place.

All this length is what will lay outside of the length of the actual stay. Now that the tail portion is calculated, measured, and marked, it is time to measure out the length for the actual stay.

The length of the stay is the span from mast tang to chain plate minus the four feet of the lashing and deadeye. For the sake of the example, let's assume that the distance is 50 feet. If you are going to have 3 feet of lashing and 1 foot in the deadeye, this would mean that 50 - 3 - 1 = 46 feet of length.

Your length of line would be as follows:

2 feet for taper

2 feet for bury

8 inches for thimble

46 feet for stay

8 inches for thimble

2 feet for bury

2 feet for taper

As you can see, the cut length of 51 feet and 4 inches long.

When you finish fabricating the stay, you will notice that it will be much shorter than 46 feet long that you were trying to achieve. This shortness is due to the constructional stretch, which at this time can be thought of as potential constructional stretch.

The more weave you opened to perform the splice, the shorter the stay will appear to be. Upon initial tensioning, this stretch will be removed and it will nearly approach the ideal 46 feet of our example. After a bit of creep during Phase I of the dyneema lifecycle, you will find that it will reach closer and closer to the ideal 46 feet desired.

This is very important when working with headstays, where you want the eye splice to sit as low to the deck as possible, allowing you to have your first hank attach to the stay as soon as possible. Proper measuring can safely place this eye 24 inches above the stem, where the deadeye is 12 inches, and the other 12 inches is the lashing.

If you have to err, it is best to err on the short side. If your stay is too short, the stay will have a longer lashing and will still achieve the same amount of proper tension. If your stay is too long, you will end up two-blocked and you will need to redo your splice and tension it all again.

Lifting with your Rigging

Sailboats can be viewed as delicate creations that glide across pressure differentials in the air and water. Following this logic, you would be inclined to fear using your spars and rigging for anything other than sailing.

This is where davit companies take over, offering you an easy way to create a crane arm on your yacht that will lift your dinghy and outboard motor.

If you want to hang your dinghy on the stern and you don't have over-extending spars, then yes, you will need davits. If you are willing to place these heavy objects on the deck where they would be within the reach of the spars, then no, you won't need davits.

Davits are merely miniature replicas of what you already have, a mast and boom. The mast provides the vertical fixation point while the boom offers the horizontal fixation point. Using the two of these in tandem will allow you to easily lift and position any object you want onto your deck.

To do this, the first thing you need to do is stop viewing your rigging as a setup for sails and instead view it as a crane. The halyard is your hoist and your boom is simply the lateral positioning.

To carry this out, all you need to do is run a line from your mast out to the end of the boom and back. You will tie a bowline around the halyard in the end of this line after it has returned from the end of the boom.

This line is your outhaul and will position the object you are lifting along the boom.

To raise an object, you simply need to attach your halyard to it and begin cranking on your halyard winch. The outhaul will position it on the boom, so it is best to start with the outhaul all the way at the end of the boom, that way gravity will aid you in bringing it closer to the mast.

You can lift the object as high as the boom, and the boom can be lifted by way of the topping lift, giving you great flexibility in how you will manage your cargo. Once the object is clear of the lifelines by lifting it with the halyard, you can begin to ease the outhaul to bring it closer to the mast. When it is in the position that you desire, simply swing the boom over and it will bring the cargo with it.

Once it is over the area of interest, you can ease the halyard to lower it onto your deck.

Using this method, you can easily and safely remove and reinstall your inboard engine, as well as launch and retrieve your dinghy if you keep it under the boom behind the mast.

I keep a special line with a large thimble spliced into the end for the outhaul. The thimble reduces the friction and chafe between the outhaul and halyard, increasing their longevity. If this is a one time thing though, fire away with a bowline and get the job done!

Gantline Setup

Climbing the mast usually involves conning one of your friends to haul your heavy body up the spar so you can take a look at a few things. If you run out of friends who are willing to spend their day grinding on a winch, you will need to find a way up to the top and back to the deck in a safe manner alone.

One of the easiest and safest ways to climb the mast alone is to use a gantline. A gantline is a dedicated line that will raise a human up the mast. It is simple to rig and easy to use.

The gantline is made up of a pulley which is attached to a halyard. This pulley will be a double block. On your chair, you will have another block; double if you want to create a 4:1 system, or single if you want to create a 3:1 system. Between these two pulleys will run the gantline, which you will pull to raise yourself up the mast.

Some things to consider when choosing your system is how strong are you and how much do you weigh.

If you choose a 4:1 system, your weight will be divided by 4, but you will have to pull 4 times the height of your mast in rope to get yourself all the way to the top. If you weigh 200 pounds, and your mast is 50 feet tall, you will have to pull a weight of 50 pounds 200 feet. The weight is slight, but the distance is great and you will need a lot of endurance to make it all the way to the top.

If you choose a 3:1 system, your weight will be divided by 3, but you will only have to pull 3 times the height of your mast in rope to get yourself to the top. If you weight 200 pounds and your mast is 50 feet tall, you will have to pull a weight of 67 pounds 150 feet. The weight is slightly more, but the distance is vastly less. If you are strong enough, I highly recommend going with a smaller system, as you will get to the top faster and you will need less rope to do so.

The gantline is run through the blocks and tied off to the last block after all the pulleys are used. If you are using a 4:1 system, the knot will be on the top block. If you are using a 3:1 system, the knot will be on the bottom block. To go up, all you need to do is pull on the tail and you will slowly begin to ascend.

Coming down is easy too, as you let the line out, you will slowly descend. The friction from the pulleys will also cause you to come down a bit slower as well. If you loose your grip on the tail and begin to freefall, all you need to do is grab the mass of line that runs between the blocks and squeeze. The rope will stop moving and you will come to a stop without hitting the deck.

I like to use 3 strand nylon rope for my gantline because it is easy to grab and also easy to inspect the condition. Double braid rope can have a nice looking cover and a rotten core hiding below, waiting to fail while you are aloft. 3 lay is the entire rope, and what you see is what you have. If you notice severe chafe, you can easily identify it and repair it with a mending splice, or replace the entire rope if you do not feel comfortable with the idea of repairing rope.

Gantlines are a great method to raise yourself up the mast in a controlled and safe manner. They reduce the weigh involved which means that you can pull yourself and your tool bag up to the top of the mast with ease and peace of mind.

Bolt Orientation

When through bolting hardware, you might not pay much attention to which direction the bolt is facing. This may seem like a very mundane point to ponder, but this small detail can have a significant effect on the outcome of your project.

You may feel inclined to simply insert the bolt from which ever side you are standing on, but the truth is there is a right and wrong way to position a bolt.

To begin, lets look at a standard bolt. You have the head, smooth shank, and threaded portion. The head allows you to grasp the bolt with tools such as wrenches and sockets. The smooth shank is often overlooked, as it merely connects the head to the threads. The threaded portion is where the opposing nut attaches to give a bolt its fastening abilities.

The truth is, the smooth shank that is often ignored is actually the designed load bearing area of the bolt. This region of the bolt bears the most bulk and thus strength of the bolt. The threaded portion is actually significantly thinner as the threads are cut in, making the thickness of material reduced by the depth of the threads.

If you through bolt a high sheer stress object with the nut facing the most load, you risk sheering off the nut and causing a catastrophic failure to whatever you were trying to retain. The head should face the high strain working areas, as the head is right next to the smooth shank and thus is the strongest side of the bolt.

In the example below, a bracket was through bolted to the mast that will act as the attachment for all the turning blocks. Under full load, this bracket will be subjected to the full fury of the reef lines and main halyard. Since the halyard is located on one side of the bracket, that side will also be bequeathed with the heads of the bolts. The other side which will be under slightly less load will contain all of the acorn nuts used to hold the bolts in place.

Next time you go to through bolt a piece of equipment, be mindful of which end will be subjected to the most strain and place the heads of the bolts accordingly.

How to Tell if the Shrouds are Tight Enough

Adjusting the standing rigging may seem straight forward, simply tighten the stays until the mast is in column and in the correct order that way everything lines up and works well together. The problem is, how tight is tight enough?

You don't want to over tighten the stays because the additional stress is just that, additional stress. This stress is transmitted to the spar, the mast tanks, the chainplates, the hull, pretty much everything that is involved with the rigging will now be subjected to unnecessary additional stress.

There are two ways to check the tightness of the rigging, one is at the dock, the second is while sailing.

The dockside check is rather simple, all you need to do is feel how tight the cap shrouds are. They should be tight enough that when you push or pull on them, they don't want to jiggle around too much. If they feel loose or floppy, you need to tighten them further. 

Once the cap shrouds are set, the rest of the shrouds simply follow in sequential order with none of them being tighter than the cap shrouds.

The second method, and the preferred method, is to sail test the rigging. This will subject the yacht to the real loads that it is expected to perform under. If the mast is not in column while sailing, the windward shrouds are too loose and need to be tensioned further. If the mast is in column but the leeward shrouds are floppy, the leeward shrouds need to be tightened to remove the slack.

Eventually, rigging perfection will be reached where the shrouds are the perfect tightness. The mast remains in column on all points of sail and the shrouds never go dangling slack. 

The reason really slack leeward shrouds are a hazard are all due to the practical effects they can have on the rigging. 

If the cap shroud were to slip out of the spreader tip, it would then be too loose and the spreader would no longer be working. The mast would bend violently to leeward as the overlong cap shroud is over stressed. This is why the spreader tip needs to be tied to the cap shroud, that way it won't fall out of place, even when slack.

The second reason really slack shrouds are a danger is made apparent during tacking and especially during jibing. The slack rigging is under no tension while on the leeward side. Should your yacht undergo an accidental jibe, the leeward shrouds would quickly become the windward shrouds in a violent display of force.

The slack shrouds will be shock loaded, and these shock loads can be tremendously greater than what the stay is able to withstand. An accidental jibe could actually snap a stay, which results in overloading the remaining stays and potentially bringing down the mast.

If the leeward shrouds are kept in slight tension, they will not go from slack to fully loaded in an instant and the rigging will have a better chance of surviving a fierce accidental jibe.