Looking at Wire Rigging

I know I focus a lot on Synthetic Standing Rigging on this blog, but there is one important point to make about all rigging: They work until they fail.

Replacing steel standing rigging to synthetic standing rigging is a waste of money. Rigging is expensive and while synthetic standing rigging is cheaper than steel standing rigging, the cheapest standing rigging is the one you already have!

This is why I feel it is important to know how to look at your steel standing rigging to better determine when it needs replacing. Once your rigging needs replacing, that is when deciding what material to go with makes monetary sense!

This is what your standard 1x19 Stainless Steel wire (304, 316, or 316L) should look like. All the strands are pretty, polished, and clean. There are no signs of corrosion or other problems with the wire. Dirt is a fact of life and should not be a cause for alarm. Some boat owners go above and beyond to keep dirt out of every surface of their yachts; and while this is a positive trait in someone selling you a boat, it is also not practical or realistic to keep every inch of wire on a sailboat clean and free of dirt or debris!

Now we start to see problems develop. This wire is still in adequate condition for now, but its end is approaching. This is when you should begin saving up for the cost of replacing your rigging and deciding what material you wish to replace your standing rigging with!

Are you going to replace your rigging yourself or are you going to pay a rigger to do it? If you are going to pay someone, will they come to your boat or do you need to take your boat to the yard where they work? This would also be a good time to start collecting estimates from different riggers that way you know where you will be going when the end of the line finally comes.

When your rigging looks like this, you can still sail on it, but you need to keep a close eye on your rigging because it is dying. It is not dead yet, but it will be getting there!

This is what wire looks like when it is on its last leg. You can see many spots where rust is occurring. The strands have lost their luster and appear dull and tarnished. Rust spots are less the rare occurrence and more the norm, as almost each visible strand has multiple rust spots on it.

It is important to note the strict difference between rust staining and rusting metal. If you take perfectly fine stainless steel and rest it up against a rusting piece of metal, the iron oxide from the rusting metal will stain your perfectly fine stainless steel. This means that if you have a low quality piece of metal attached to your rigging and it begins to rust, the metal of the stay near this will develop a rust color. Rust stains polish off and the wire will go back to looking like new.

If the wire itself is rusting, there is no amount of polishing that can be done to remove all the rust and restore the original luster of the wire. When the stay itself is rusting, that is when it is at the end of its lifespan.

When the stay begins to corrode like this, it should be replaced promptly. Yes, you can still sail in light conditions with it as it has now “failed” yet, but it will soon fail and should be replaced.

Failed rigging is when it actually breaks, and while you can sail with your rigging until that occurs, the problem is that when a failure occurs during use, the repairs tend to be rather costly!

Imagine for a moment that you have your sailboat sitting in the slip and the port cap shroud begins to develop significant corrosion. At this point, your sailboat is sitting in the slip with the mast standing straight and tall. Nothing has broken or given way yet.

You make arrangements and either replace the stay yourself or hire a rigger to replace the stay for you. Then you go sailing with your new stay and nothing happens.

Now lets imagine the same situation but instead of replacing the stay when it was dying, you wait for the stay to fully die. You are sailing along on a close reach on starboard tack. The spray is coming over the bow and you are heeling well to leeward. Everything is wonderful and then you tack. Now all that load is on the corroding port cap shroud and the failing stay finally fails. The wires break and the mast becomes unsupported. The cap shroud had broken and the only think holding the mast up in the air are the lower shrouds! The force of the wind on the main and headsail pull harshly against the top of the mast which is no longer being supported by the port cap shroud and the mast begins to bend. The mast bends further and further causing the sails to become baggy and hold even more wind, and pulling even harder on the unsupported mast until it buckles at the lower spreader attachment.

Now you have a broken mast as well as a failed port cap shroud!

This is why you want to replace your stays when they are failing instead of waiting for them to fail.

Going up!

A little real-time update:

We made it back to the boat, I measured our inner forestay, I manufactured our new inner forestay out of DM-20, and I installed our new inner forestay.
The entire process was incredibly rushed. I usually work for a few hours and then take a break because my hands get tired, but we only had 2 days available to get it done, so the first day was spent making it and the second day was spent installing and stretching it!

This was my first time working with DM-20 so there was a small learning curve involved but I will go into all those features in much deeper depth in the future!

How to Install a Cotter Pin

Cotter pins, also called Split pins, are a retaining pin used to hold other load bearing pins in place. The goal of a cotter pin is to remain in place. The legs are spread to keep the head in place so that the pin doesn’t fall out.

There are two methods to bend the legs:

1. Bend the legs 15*

2. Bend the legs all the way back up and around

By bending the legs 15*, the pin is held in place with minimal strain on the metal of the pin. If the metal legs are fatigued too much, they can break off and the head of the pin will then fall out.

Bending the legs all the way around looks more secure, but it stresses the metal a lot more than a simple 15* bend.

Watch this video to see the difference in durability between these two methods of bending cotter pin legs.

Cotter Pin Leg Experiment

In one of our videos, the amount I spread the legs of a cotter pin was brought into question. I spread the legs 15 degrees because that is what I learned when I was reading about rigging.
The rationale behind it is the cotter pin legs need to be spread enough to hold the pin in place. The more you spread the legs, the more the legs will be able to hold the pin in place; but the more strained the metal will be and that could lead to the leg breaking and failing to retain the cotter pin!

The two schools of thought are: 15 degrees or wrap the legs around so they come back and touch the head.

Which is better? Which is stronger? How much is the metal stressed in the process of bending?

I set out and tested this very question and will be making a video about it shortly, I just wanted to let you guys know about this project I’m working on!

Some quick results:

Test 1: 15* 487 cycles, 90* 44 cycles

Test 2: 15* 545 cycles, 90* 85 cycles

There is a bit of spread between the two tests, but the results are pretty consistent that spreading the legs 15* hardly strains the metal while bending the legs 90* is 10 times more stressful to the cotter pin!

Galvanic Corrosion on your Mast

Galvanic Corrosion is a silent killer of your wallet. It starts off so quietly and slow, barely noticed until it develops into a very expensive problem that will cripple your aluminum mast!

This mast has been pulled for winter storage of the yacht. The spreaders are neatly stowed inside the hollow spar for safe keeping. The bottom of the mast where it rests over the mast step is bubbling up with galvanic corrosion and this means that the mast is slowly but surely dying right at the base!

In a situation like this, the mast base will eventually become too weak to support the loads it is subjected to while sailing. The mast will ideally crumble down onto the mast step and all the rigging will go slack as the mast instantly becomes a few inches shorter. We all know that nothing on a sailboat breaks ideally, and instead the good aluminum just above the step and bad aluminum will slip off to the side of the step and the whole mast will come toppling down in a horrific and catastrophic failure of the rig!

For comparison, this is a perfect mast with absolutely no problems occurring at the step! Now, why is this happening to the first mast and not to this mast? Well, to put it simply, it’s because this mast is fully protected by paint and other insulating layers. There is no contact between the aluminum of the spar and any other metals, hence no cause for galvanic corrosion. The mast above must have a tiny scrape in the paint or contamination with a different metal around the mast step because the damage is localized only to the step of the mast and no further.

The damaged mast doesn’t need to be replaced, the solution is actually quite simple. The affected portion of the spar should be stripped bare and evaluated. If the corrosion is too extreme, the section is simply cut off and the mast made shorter. If the corrosion is minimal, a new coating of paint is in order to isolate the metal and protect it from further and future corrosion. Lanolin can also be used around the mast step to act as an insulator and protect against galvanic corrosion where the mast meets the step.

This mast, however is suffering from much more crippling damage.

You can see the paint bubbling up around the screw holes. This is caused by galvanic corrosion between the stainless steel screws and the aluminum spar. Apparently, no isolator was used, and if one was used, it has failed as isolating the two dissimilar metals leading to galvanic corrosion of the aluminum. The problem with this is the location.

Unlike with the other mast where the damage was located at the bottom of the spar, this corrosion is occurring on the side of the mast. If left unchecked, the side will form a hole and severely weaken the mast. This area is also in one of the highest stressed areas of the spar: The head.

All the forces of the sails, halyards, and rigging culminate at the head of the mast in the area of the truck (where all the welds are) and this is exactly where those little screws are bubbling away the aluminum of the spar. Eventually, the mast will break and make a big mess of the boat below it!

The corrosion still looks minimal and the screws do not appear overly critical. They could easily be removed and the area cleaned and protected. If they are necessary, then they can be coated in lanolin and reinstalled, paying close attention to the area in future rig inspections for any sign of renewed corrosion in the area.

If these small bubbling corrosion points are left unchecked, they can lead to very dramatic and costly results. Be sure to check any fasteners in the mast with a close eye and hold the area to the utmost standards of perfection. When it comes to your spar, there is no “good enough”!