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The Sailboat Diaries: A Leak Fixed and a Keel Leashed

Posted December 13, 2017 10:53 AM by HUSH

Blogger’s note: Documenting all the restoration work for The Sailboat Diaries has been about the only project slower than the boat work itself! We’re on schedule for an official relaunch in May. While the winter keeps me indoors, I’ll do my best to get these posts up to speed.

Hang around the marina and you’ll eventually hear the sailing adage that goes, “There are two types of sailors in this world: those who have run aground and liars.”

Keeping this in mind, I cannot judge whoever ran my poor 1970 Matilda 20 aground at some point. Even the most mindful sailors sometimes get into a navigation accident (the U.S. Navy is a recent prime example). However, I can certainly judge the repair ‘work’ conducted afterward.

Memory refresh: This boat has a drop keel that descends from a wooden trunk in the middle of the vessel. The 350 lb. steel wing and bulb is supported by a wire rope and pulley system that allows the helmsman to adjust the keel height based on the sailing conditions.

Trunk Reform

At the base of the trunk there is a limiter bolt that prevents the keel from descending too far and dangling helplessly, as the boat risks capsizing. Or you know, at least there would be, had someone not run aground keel-first and smashed up this section of the keel trunk, in all likelihood destroying this assembly. A subpar DIY repair resulted in a mysterious material plied all over the aft side of the trunk that stymied but ultimately failed to stop the resultant leak.

I bought this boat off the water in September 2016, so I knew there was a leak in the hull. Before setting off on a trial sail, there was about an inch of water covering the sole of the cabin (in addition to the inch or two that had filled the bilge) and upon return the water level was the same.

Apparently the boat’s then-owner had sailed her for two summers in that condition, preferring wet feet over the elbow grease to fix the ingress. He more or less knew where the leak was coming from, although he had no idea the extent of the damage.

My first task was to verify that this was the only leak in the boat. Since the engine was still laid up from the off-season I elected to fill the inside of the boat with water, which I then dyed red with food dye. I taped some paper towels to plywood and settled the boards under the trailer. Within a few hours I had two red puddles absorbed into the paper towels. There was in fact another very small hole about 6 in. to starboard from the keel.

Now that I had isolated the problem areas, I got to work chipping away at the mysterious repair substrate on the trunk with a small chisel and hammer. I suspect that this may have been a type of marine repair putty that isn’t really meant for repairs of this scale. Chiseling gave way to sanding and grinding. After several days I finally revealed the extent of the crack that was producing most of the leak.

At this point the boat interior was completely covered in dust and debris as well as some superficial redness from the food dye, so a wash down was needed, as was a more thorough cleaning of the work site.

The crack was about 12 in. long and less than 1 in. from the floor of the bilge. About half the crack was located along the starboard side, while the reminder wrapped along the back face and port side of the trunk. Once this was revealed I chamfered the edges to extend the adhesion zone where I would lay marine epoxy.

I precut sections of Owen Corning U1200HD fiberglass roving to match the work site. Smaller pieces go on first, and the crack itself would receive three layers of roving, while adjacent areas received two.

Once again I used System Three marine epoxy filled with colloidal silica. However, in this instance I used enough filler to thicken the epoxy to a peanut butter-like consistency. I applied the filled epoxy with a putty knife and smoothed it out as I went along. The first layer of roving was applied before more epoxy was added. Another layer of fiberglass, then another layer of epoxy, albeit with less filler and applied via paint brush. Rinse and repeat once more until all the layers of roving were added.

I also used some marine epoxy to fill in the other small hole nearby. I sanded some edges of the epoxy, wiped it down and then applied blue marine paint to the location. This helps hide the texture of the roving and epoxy by blending it in with the bilge cover. This area had been painted brown prior to sanding, so it needed the attention for aesthetic reasons anyway.

I think I was able to apply a lot of the experience I had from working with the marine epoxy before. The repair came out excellent and is quite easy to overlook. While I did fill the boat with a few inches of water once again to check for a leak, we won’t really know the integrity of this repair until the vessel is relaunched in spring 2018. Nonetheless, I feel confident that the leak has been permanently addressed.

Tackling the Block and Tackle

Back in June CR4 was pretty helpful with the tackle setup for the keel. At the time, the primary challenge was figuring out a means to prevent the keel from descending too far, as the limiter bolt is missing. I also need some advice on swage sleeves versus U-clamps for terminating wire rope loops, as the current wire rope and wheels were considerably rusty. Replacing the wire rope and U-clamps was fairly simple: both were replaced with stainless steel counterparts.

However, finding replacement pulleys was quite a problem. I spent more than two months scouring the internet seeking a stainless steel or other corrosion-resistant metal pulley, with an outer diameter of 2.5-3 in., an inner diameter (ID) of .375 in. and suitable working load. I had even ordered ones that might work (these ones, although I did not order from Grainger), but the ID was too small.

After speaking with customer service, I couldn’t find the right parts. Ultimately I chose to clean up the pulleys that came with the boat. After a baking soda scrub down with a toothbrush I was able to remove a lot of surface rust. I added some WD-40 to the pulley surfaces before reinstalling, but I still intend to replace these at some point. For now, they’ll do.

Now I had to focus on keeping the keel inside the boat. The first repair choice would be to replace the limiter bolt, but this would require finding the correct replacement. In all likelihood the bolt was stainless steel, but the diameter would need to be found and fasteners and washers might be a trial and error situation.

There was also no telling what the structural shape of the white oak is where the bolt once resided, so inspecting this area would require removing the keel. That means a trip to a boat yard or a crane rental is in order. I would also have to split open the trunk from the inside, which although isn’t unfixable, creates another repair project altogether.

Instead, I elected to create a rope wire leash. Wire rope was measured and looped; the hanging loop was attached to the non-rotating lead pulley, while the opposite loop was connected around the lead pulley connected to the keel, which does rotate. Ultimately this will allow the keel to be lowered from a 9 in. to 3.5+ ft. draft. When the keel is lowered to its maximum, the burden will be taken off the rachet winch. The operator will feel the load taken off the winch and will need to back up on the winch a little bit so that the tackle is supporting the keel load, not the leash.

As before, this is the part where I confirm all these projects were rousing successes, right? Not so.

At best, these projects get an incomplete.

Keel trunk leak: probably fixed, but too soon to tell for sure.

Keel leash: I am worried that the U-clamps could jam the keel when it is being retracted. This would be an easy fix while under sail, but not something that I want to deal with every time I need to tack or jibe and raise the keel. Again, I won’t know how effective the leash will be until the boat hits the lake. This may well be a trial and error type issue.

Keel pulleys: I’m comfortable moving forward with the stock components, but they are almost 40 years old and have some minor corrosion and misshapenness. They are at least clean now.

There are some issues I will circle back to, at least for an update it nothing else.

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#1

Re: The Sailboat Diaries: A Leak Fixed and a Keel Leashed

12/13/2017 10:36 PM

Nice report. Thank you.

Consider using a bungee or similar to keep the leash and uclamps from getting into a position likely to cause binding.

When you say "chamfered the edges" does that mean grinding out the crack and any surrounding damage completely, or does it mean beveling the edge of the crack, but not grinding the full depth?

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#2
In reply to #1

Re: The Sailboat Diaries: A Leak Fixed and a Keel Leashed

12/14/2017 9:24 AM

I widened/opened it up just enough to pass the edge of the metal putty knife through so I was able to smear the fiberglass epoxy through the entire depth of the crack (or at least most of it). From underneath the boat, you can see where some of the epoxy seeped through to the other side, but it doesn't affect the keel movement (at least on land).

Unfortunately the images in this post don't do it justice. I don't even have a current image of what it looks like fixed, and the boat is now wrapped in a tarp under a partial A-frame, so it's not easy to get inside at the moment to snap a pic.

I will try a bungee! Nice idea. Even if I have to replace it every year or so, it might be an easy interim fix.

I'd still like to replace the pulleys, so once I can afford to have custom ones made (or I stumble upon them somewhere), I might upgrade to a design like in this image. It's actually where I got the leash idea from. It's also from a Matilda but with a different set of keel issues.

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#3
In reply to #2

Re: The Sailboat Diaries: A Leak Fixed and a Keel Leashed

12/15/2017 11:39 AM

About the the keel cable. Have you considered a cable stop on the live end of the actuating cable. I assume you lift the keel with a hand winch. You can swedge a stainless steel cable ferrel at the appropriate spot on the cable so that when it encounters the lead sheave (pulley) it locks the cable. The round shape of the ferrel should not impede the winch.. A little preshaping of the leading end of the ferrel with a 40 grit sanding/ polishing disc on a 4-1/2 inch mini-grinder will prevent jamming in the sheave.

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#4
In reply to #3

Re: The Sailboat Diaries: A Leak Fixed and a Keel Leashed

12/15/2017 12:54 PM

Indeed, here is the winch. The first block and the rope has been replaced since.

The winch is located in the cockpit. The wire rope runs from the winch through the aft cabin fiberglass bulkhead, where it is then exposed for it's roughly 3 ft. run through the cabin, before entering the first pulley at the top of the keel trunk.

To do this I'll need to fully extend the keel. This could end up being an on-the-water fix that I can do once anchored.

Extend the keel>visually confirm the keel is at its max>then add the sleeve.

Do they make split sleeves that I can place on an in-situ cable?

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#5
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Re: The Sailboat Diaries: A Leak Fixed and a Keel Leashed

12/15/2017 1:24 PM

About the sleeve. Split? not that I know of, BUT, depending on the hole size through the bulkhead, it seems you may have enough run on the cable to use a simple cable clamp. FYI: it is part of my job as Technical Partner for a "big steel" design, fabrication and installation finding elegant Oxam's Razor answers for arcane problems.

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#6
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Re: The Sailboat Diaries: A Leak Fixed and a Keel Leashed

12/15/2017 1:30 PM

Good stuff. Definitely going to have to circle back to this one way or another.

I cannot risk a sailboat with a keel!

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#7

Re: The Sailboat Diaries: A Leak Fixed and a Keel Leashed

12/18/2017 4:34 AM

Great write up, and nice to hear the full story following the earlier posts :)
Looks like you did a great job, I'd only suggest you could maybe get someone to bore out the ID of the pulleys that you bought, as spares for any later work/refurb?
Look forward to seeing her in the water :)
Del

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#8
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Re: The Sailboat Diaries: A Leak Fixed and a Keel Leashed

12/20/2017 10:04 AM

Unfortunately the inner diameter has a polymer sleeve that makes the dimension closer to 0.25 in.. Removing it altogether makes the bore too large.

I returned the first batch I ordered and the company said they sent me the wrong size. OK. Well the next batch was exactly the same. I got the money refunded, but I refuse to buy anymore 1RCV3 sheaves. The inner diameter is NOT 3/8".

Will try to post pic later of these blasted things.

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Re: The Sailboat Diaries: A Leak Fixed and a Keel Leashed

12/20/2017 10:49 AM

Yeah, that's the curse of modern business, a lot of 'em have no understanding or knowledge of the products they sell.
Del

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