Rigging, Standing, Mast Compression Post, Repair

One part of the mast compression post repaired and ready for reinstallation
A mast on a sailboat is either keel-stepped or deck-stepped. If it is keel-stepped, it sits upon a foundation of some sort atop the keel. If it is deck-stepped, it sits upon the deck. The deck of a sailboat, however, is not typically strong enough by itself to support the weight of the mast (and the downward force it exerts due to its rigging). Therefore, the deck itself of a deck-stepped mast must be supported by a post, which itself sits upon a foundation of some sort atop the keel. In this regard, the keel-stepped mast and the deck-stepped mast are similar.

The mast on the Ericson 25 sailboat is deck-stepped, and beneath the mast there is a post. It's not a solid post, but this does not mean that it's not substantial. After all, hollow posts are commonly employed in the construction business. On three of its sides are solid mahogany boards, one inch in thickness. Its fourth side is a portion of the bulkhead itself. This hollow post sits atop the fiberglass trunk of the Ericson 25 centerboard. The centerboard line, in fact, passes upward through this trunk and through the post itself on its way to the deck.
I purchased my Ericson 25, Oystercatcher, in the fall of 2009 from a person in the Outer Banks region of North Carolina.
This person had long neglected the boat while it sat at his personal dock. He cleaned her up when he put her on the market, but there were many things that were amiss if you cast a critical eye in any direction.
One thing that I noticed in one of my visits to see the boat was that her mast compression post was out of alignment. The mahogany board adjacent to the door of the head projected outward at its base.
Because of her numerous issues, I was able to obtain the boat for much less than the asking price. A friend and I sailed her away from the owner's dock, spending two nights aboard her in our transit to Oriental, North Carolina for haulout.
From there we trailered the boat back to my home in Charleston, South Carolina.
Knowing that I had to address some problems, I removed the mast from the boat and built sawhorses to support the mast in my backyard.
I took many steps over time to upgrade the boat and the mast. One of these upgrades concerned the replacement of the spreaders and spreader brackets. For more on this and my work in general in this regard, see my numerous articles in the Index under the headings of "Spars" and "Rigging."
It was around the same time that I replaced the spreader brackets that I also at last sought to address the mast compression post problem. It was around this same time that I was also rewiring the boat. The mast compression post problem stood in the way of my some of my rewiring goals, so now was a great time to tackle this.
When I looked carefully at the centerboard trunk - the foundation, if you will, of the mast compression post - I discovered that on its port side the fiberglass of the trunk was not level.
The fiberglass flared upward at an angle. This flare was preventing the piece of mahogany on the port side from sitting perfectly flat upon the centerboard trunk. At first I thought that this flare might have resulted from a hard grounding of the boat. I knew from evidence on the hull in the vicinity of the centerboard that the previous owner at some point had run the boat aground.
I tried to grind down the flare with a fiberglass cutting bit attached to a Dremel. This didn't work well, especially because the piece of mahogany was partly in the way. It looked as though I would need to remove this mahogany in order to do the job right.
It took a little more work to remove this piece of mahogany compared to the one I had already removed. Ericson had set its screws at an angle in order to join it to the plywood bulkhead. You can see the head of one of the screws in the picture below.
The black plastic tube made it difficult to access the screws. This tube had formerly housed the VHF coaxial cable. I would no longer be routing the VHF cable in this direction, so I opted to remove the plastic tube at this time.
I didn't have much of a choice. The tube was bound to the mahogany with a white plastic bracket. To complete my removal of the mahogany I had to remove the bracket and thus the tube from its surface.
At last the mahogany came free.
Now I could more easily work on the oddly shaped piece of fiberglass that flared up from the centerboard trunk.
Attaching a 50 grit sanding drum to the Dremel, I got to work leveling the flare. The more my friend and I analysed the work area and the mahogany itself, the more we began to think that this oddity was not the result of a hard grounding but was instead the result of something that went awry at the time of manufacture. It looked as if the fiberglass shaft for the centerboard line had distorted the trunk.
Over the years, the mahogany itself had become distorted from not sitting properly atop the trunk. Here we are looking at the base of the mahogany. I have simply propped it up in the companionway of the boat for the sake of taking this picture.
This side of the mast compression post actually consisted of not one piece of mahogany but two. The small piece that you see pictured below served as a stop for the mahogany door to the head.
This stop was also a contributor to the problem. Its distortions prevented the board from sitting properly atop the centerboard trunk.
My plan at first was simply to remove some of the old screws from this stop and then install some new screws that would pull the two piece of wood together. The problem was that the heads of the old screws were concealed behind mahogany plugs. Rather than removing the plugs and thus the screws, I thought I could get away with simply cutting off the ends of the screws with the cutting wheel on my Dremel. This, though, didn't really solve the problem. The pieces of the screws that were still within the wood were preventing the two piece of mahogany from sitting together properly. This in turn was preventing the entire assembly from sitting properly atop the centerboard trunk.
This led me to believe that I could get away with simply sanding off some of the material from the bottom of the board.
Likewise, I also thought I could make things better by sanding the top of the trunk a little bit more. I was hesitant to make this area perfectly flat. The more I reduced the angle, the more fiberglass material that I removed from the foundation. I should point out at this time that this thick fiberglass was not the true trunk for the centerboard, rather it was the liner that covered it. In other words, this was part of the liner that surrounded the interior of the hull. As I said, though, this stuff was thick.
These quick fixes helped a little bit, but they did not really solve the problem. I did not take a picture of the door stop, but it was still distorted at this time.
Reluctantly, I decided to halt my progress in the rewiring of the boat and instead focus on fixing the mast compression post the right way.
Over the years, water had dripped down the black plastic tube and had damaged the base of the mahogany. It wasn't rotten, but it was damaged.
The picture below should give you a better idea of the distortion that was present in the door frame.

I slowly pried the two pieces apart, removing whatever pieces of hardware I could along the way.


I discovered that previous owner had driven six finishing nails into the frame in an effort to achieve a quick fix. His quick fix didn't do anything but make my true fix more difficult.
There was also dried glue or Great Stuff spray foam left over from the previous owner's quick fix.


After I had gotten the surfaces cleaned up, I dry-fit the two pieces together to ensure that everything would line up well when the time came for me to lay down the epoxy and screw it all back together.
At this time I also repaired a small split on the opposite site of the mahogany board. I pre-drilled and pre-screwed three holes that would received stainless steel wood screws and epoxy.
The last step before mixing up the epoxy was to wipe all of the relevant surfaces with acetone to ensure that they were free of dust and other contaminants.
Then came the epoxy. I started by wetting out all the surfaces with neat (unthickened) epoxy. I then thickened the epoxy with colloidal silica to the consistency of peanut butter and spread it on the surfaces.
Notice the end-grain of the mahogany board. It greedily soaked up the neat epoxy. I would continue to hit this end-grain for several days while I did other, unrelated epoxy work. Eventually, the end-grain became saturated, and when fully cured, glossy in appearance.

Now it was time to fill the screw holes with mahogany plugs. From a practical standpoint this was not a necessary step, but from an aesthetic one it was. I had used a plug cutter to make mahogany plugs for the bookshelves that I had created. This job required smaller plugs, so I went and bought a smaller plug cutter from the local hardware store.
The cutting of plugs is an easy task, and it's a good way to make use of small pieces of scrap mahogany.
Using Titebond II wood glue, I gently hammered the plugs into place. If this had been an exterior application continually exposed to the elements, I would have used Titebond III, which is an even heartier exterior glue than the already hearty Titebond II.
I allowed the glue to cure fully, and then I came back with a hammer and chisel to remove the protruding parts of the plugs.
Now is the time when I would normally stain and varnish the unfinished mahogany. I decided, however, to leave these plugs unfinished at this time. There were some interior pieces of trim that I had installed and decided to varnish at a later date. I figured that I could do these plugs at the same time.
Now at last I could get back to my rewiring project. As a part of this project I was grounding the rig in order to provide some protection in the event of a lightning strike. I was running 6 AWG cables from all of the chainplates to the bronze grounding bolt in the bilge. The routing of almost all of these cables presented some challenges, and the routing of the cable through the head was no exception.
Routing it downward from the chainplate was not a problem. It was the routing of it over the centerboard trunk that was the problem.
In the Ericson 25 there are two forward bilges, one on either side of the centerboard trunk. In the picture below, you see the access to the one beneath the head. It's the piece of mahogany in the sole of the head. The access to the other bilge is underneath the carpet, just in front of my feet. It's in this bilge that the grounding bolt is located. Since the centerboard trunk is a barrier between the two bilges, it was not possible for me to route the grounding cable downward into the bilge in the head. Instead, I had to rout it over the top of the trunk and down through it to the other bilge.
After a lot of feeling around in the dark, I had determined that there was a small gap between the centerboard trunk and the thick liner that surrounded it. This gap was large enough to accommodate the cable, so it was here that I had drilled a hole.
The grounding bolt with the grounds from all of the chainplates and from the AC and the DC electrical systems.
At this point I'd not yet grounded the mast. This mast compression post project was blocking my progress on that front.
Something else that was blocking my progress was the mahogany board that I had repaired. Now that I had including a grounding cable into the mix, I had to cut a notch in the board to make room for it.
After making quite a few adjustments to the notch I was able, at last, to reinstall the mahogany board.
This task was much easier now that I no longer had to deal with the annoying black plastic tube that had formerly obstructed my view and my screwdriver.

Here's how it looked inside the head at this stage of the project. The conduit is for the new mast wires.
Before I could reinstall the mahogany board that faced the main salon I had to reeve the centerboard line through the centerboard block. I had constructed an entirely new centerboard, and I had gotten a rigger to create an entirely new pendant for the board. Now I had to join the old block to the new pendant.
I routed the new centerboard line down through the new mast step that I had just installed. For more on this, see my multi-part article, "Spars, Mast Hinge."
While the boat may look like a mess, it was actually quite clean at this point. There was a long period of time when it was coated with mildew and epoxy dust.

I tied a bowline (with a half hitch) to the stainless steel loop at the top of the compression post.
Here's what the completed installation of the centerboard line and pendant looked like.
There were still several things I needed to do before I could put the mahogany back in place. The first was to remove old adhesive residue that still clung tenaciously to it.
The previous owner had stuck some old plastic thing-a-ma-jig to it at some point in the past. I don't even remember what it was - a thermometer or something - but I didn't like the way it looked.
I did, though, like the bronze placard. This is one of the few things original to the boat that I did not throw away or alter. At the time I visited the boat and purchased her in the fall of 2009 I found this placard to be meaningful - a seemingly providential indication that this was the boat for me.
In the summer of 2006, my family and I had traveled to New England in our Toyota SUV where we tent-camped for some three weeks. While there, we visited New Bedford, Massachusetts, the heart of the whaling industry long ago. In New Bedford itself, we visited the Seaman's Bethel, a church that had been frequented by whalers before heading to sea. It was in fact here that Herman Melville himself had sat, and it was in this church where his character Ishmael sat in the opening pages of his epic novel, Moby Dick. The sanctuary of the church was lined with placards old and new in memory of those fisherman who'd been lost at sea.
All of these placards I found fascinating, but none more so than a recent one with the words, "O God Thy Sea is So Great And My Boat Is So Small." I took a picture of this placard as a memento.
Shortly afterwards, on the same day, we visited the New Bedford waterfront, a place still teaming with commercial maritime activity. At that moment, a wooden tall ship, the Lettie G. Howard, had just docked. There were young people aboard who had been offshore for many days. This was a sail-training vessel whose purpose was to expose students to the sea, so as to foster in them a greater sense of self, teamwork, and purpose. These students, from the inner-city of New York, were dazed and confused, yet enlightened. They had successfully passed through a storm in the night, and they felt empowered.
A few hours later we were back in our campsite, on the shore of Buzzards Bay near Cape Cod. It was a peaceful evening until just around bedtime. The children had gotten in the tent, and the Admiral and I were enjoying some vino rosso around the campfire underneath a star-filled sky. Then we started hearing the low rumbling in the distance, far offshore. "Must be a passing storm. Wouldn't make sense for it to be coming inland." That's what we were thinking, but then the rumbling started getting closer . . . and closer . . . and then the clouds started coming and the trees started swaying and the dust started blowing. The lightning flashed and the thundered roared, and soon we were hustling the children from the tent into the SUV. Shortly thereafter it hit. Out tent collapsed and lost its tarp. Other tents tumbled through the campground. Several RVs that were directly in front of the beach were blown over. Eventually the storm passed, and everyone climbed out of their vehicles to inspect the damage. Everything in our tent was hopelessly soaked with rainwater. We had no choice but to sleep in the SUV. We tried at first to keep the windows down for the sake of ventilation, but after the storm had passed the mosquitoes were out for blood. I'd been through plenty of storms before, but this one impacted me unlike others in the past, given everything that we had experienced on this day.
Some seven months later I unexpectedly received the opportunity to sail aboard a sail-training vessel, the tall ship Westward. For five days in the month of January we sailed southward from Charleston to Miami.
After that I had many opportunities to sail aboard the Spirit of South Carolina and other sail training vessels. Every time I'm out there I'm reminded of that placard I first saw in the Seaman's Bethel in New Bedford, Massachusetts.
I later learned that John F. Kennedy, himself a sailor, had this very saying on a bronze placard in the Oval Office when he was President of the United States.
Now let's return to the subject at hand - the mast compression post. I removed the bronze placard from the mahogany and cleaned the entire area with Xylene - the solvent that is best at removing adhesive residue.

Having cleaned up the mahogany and reinstalled the bronze placard, it was now time to put the mast compression post back together.
The screws at the top were easy to install.
At the bottom, I clamped everything together to make sure that the screws would make everything as square as possible.
This approach worked well. The post was now as square as possible.
I still had one issued to address, however, inside of the head. The water that had dripped down the black plastic conduit over the years had created some rot on the bulkhead. To shore up the bulkhead, I cut a piece of oak to the appropriate size.
This hole did not exist before I started this mast compression post project. I created it by excavating the weak spots with a chisel. I was sort of like a dentist, digging out a cavity.
The oak added strength and would eventually add some beauty when the time came to stain and varnish it.


The project was unexpected and time-consuming, but I could now rest assured that the mast compression post was sturdy and true.
This ends this article on my repair of the mast compression post on Oystercatcher, my Ericson 25.

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