Maritime Technology

The CR4 source for all nautical topics—from boating and shipping, on salt or freshwater, for fun or commerce—all aspects of marine engineering and technology reside here. This also includes related topics such as marine products and electronics, offshore energy, marine conservation, navigation, naval defense and innovation, climate and weather, and perhaps even some relaxation and recreation.

The Sailboat Diaries: Setting Sail, part 1

Posted July 31, 2018 11:07 AM by HUSH

Apologies for the long delay between posts. Things have been hectic behind the scenes at CR4 so I don’t get to blog as often as I’d like. Coupled with a computer reformat that resulted in dozens of lost images (I stupidly forgot to back them up), there hasn’t been a ton of motivation or time to wrap up what I started: blogging about my boat refit.

Well this isn’t another old boat that ended up on “the hard” forever. She floats! S.V. Harrier was launched on Lake Champlain on May 27 of this year. After a year and a half (minus winters) of rework, replacement, refreshment and cleaning, she is moored all summer along the beautiful Adirondack coast.

So let’s tack with the wind and wrap up what I started. Here is what the exterior of the boat looks like today, after all these upgrades.

  • A new, colorful sail cover sewn by a friendly and local seamstress (thanks Sue!). I supplied pseudo-Sunbrella fabric and she provided the skill. Considering the retail cost of these, it was a bargain!
  • The front windows are newly cut acrylic. I accidentally cracked the starboard side window in the bottom right during installation, but it’s a negligible flaw. These were positioned using a construction-grade adhesive and sealant. Unfortunately, I didn’t account for CTE and the port side window has bubbled out a little bit. Right now, this is helped by some disguised white duct tape until a more permanent fix can be completed off-season. Otherwise, they are leak-free and sturdy!
  • Electrical and electronics
    • New LED navigation lights: All light fixtures were actually replaced with LEDs (except the stern white nav light). Matching red and green nav lights are mounted on the side of the cabin.
    • Note the small blue LED between the front windows. A second is mounted on the top deck, centerline, just before the cockpit. These are the first deck lights mounted on this boat, and were especially helpful one recent overnight trip to a nearby island.
    • It is tough to see in Figure 1, but hung in the window is a set of fold-up solar panels. I ultimately went with a 50 W system after this debacle. I will chronicle this a bit better when I write the blog post covering the interior upgrades.
    • o Antennas: A SiriusXM antenna is mounted centerline, just before the mast. In the port side window, an FM/AM antenna is mounted (held by the white rectangle, which are two adhesive pad mounts).
    • o At the base of the mast, a white wire extends from within the mast. I spent a Saturday night wiring and installing an anchor light at the masthead (Figure 2). The fisher’s tape was getting stuck, so I ended up taping eight thin wood dowels together to run the wire. It was a huge pain.
  • U.S. and New York flags were added as badges to the sides of the cabin. It just looks right!
  • One of the winches was seized, but both spin perfectly as disassembly, soaking in mineral spirits, relubrication and then reassembly. This requires care as the spring-loaded parts want to fly out when taking them apart.
  • Griptape on the hatch! No slick deck spots, please.
  • New lines and rigging: Docklines and anchor lines have been replace. All running rigging (both sheets, both halyards, both travelers) have also been refreshed.
  • New registration lettering. The number never changed, but since everything else was getting renewed, let’s do it too.
  • Don’t forget all the painting…
  • General cleaning. You know, sweeping, degreasing, swabbing the poop deck, that kind of stuff.
  • Finally, in the cockpit, a new varnished mahogany tiller was installed. It is a beautiful piece a wood and a pleasure to show to guests!

Here is what the stern looks like (minus the camera-blocking finger).

  • The wife had the patience to apply the flag decals and the name. They say it is bad luck to rename a boat. In this boat’s first 48 years she went nameless. Not anymore!
  • Sonar: The pod-shaped module is a flip-down transducer. The boat is outfitted with a fishing-style chartplotter and depth sensor, but it is perfectly good enough for weekends out on the water.
  • Mounted on the back rail:
  • New life ring. Man overboard!
    • This grill mount holds a 17 in. Magma stainless steel marine grill and stove. What’s a day on the boat without some grilled burgers or chicken? And we always need coffee in the morning.
    • A pennant staff. “Hoist the black!”.
    • The round tube with the no smoking decals is a DIY propane tank tube. Cut from 4 in. PVC tubing and ends caps, it perfectly holds two 1 lb. propane tanks. It is attached with ties and a bungee cord.

And now here is a few more pics of some of the summer adventures S.V. Harrier has carried us to.

(not me)

Thanks for reading and looking! I'll hope to issue part 2 in the next couple of weeks.

5 comments; last comment on 08/01/2018
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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.

9 comments; last comment on 12/20/2017
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The Sailboat Diaries: Color Change

Posted October 24, 2017 11:07 AM by HUSH

Several times I’ve read that novice boaters shouldn’t bother with cosmetic fixes to their boat. Inexperienced boaters are likely to cause cosmetic damage anyhow, so it makes sense to just make those repairs after some seasoning. Besides, boat paints typically have to be reapplied once every few years and all that time spent working could be time spent on the water.

Yet, I persisted. There were a few unsightly gouges aftward on the port side of my Matilda 20 that were created by a collapsible swim ladder. Additionally, the yellow bottom paint was peeling considerably, which affects boat performance as much as aesthetics. Lastly, I didn’t want the neighbors to think an albatross now existed in my side yard, so the optics of the situation was also a factor.

The first task was to expand the gouges a bit to create a chamfer on the edge and also allow the fairing compound to be spread easier. This was my first experience working with fairing compound. While the final result was definitely more attractive than the original gouges, the finish is still a little uneven. I resanded and faired this area three times until finally, good was good enough. I wouldn’t call this a failure as it is nonetheless an improvement, but I was hoping for a perfect result. Ultimately, working with this nasty material on a 90°+ F day was a mistake, as it was curing before I could even spread it.

Originally I had hoped to purchase some used boat stands to complete this project, but none were to be had in the local classified websites, and new set of boat stands started at $500—about 125% of what I planned to pay in painting materials. Painting on a trailer is doable, provided you are willing to sacrifice some comfort during the task and ensure the boat trailer doesn’t tip while you are under it. I cut some short 4 x 4 posts to wedge under the trailer frame to prevent tipping and also lowered the trailer jack as far as it could go. The trailer was positioned over a large plastic drop cloth and the trailer itself had a week’s worth of newspaper wrapping exposed surfaces.

Reference texts recommended that I first test the adhesion of the old paint to the hull. This is done by scoring and then applying masking tape to a few areas. If paint comes up when the tape is a removed after a short interval, then entire coating must be sanded off before a new layer can be applied. Thankfully the old coating would suffice after some sanding.

A pressure washer removed a lot of ground-in dirt and grime prior to sanding. It was surprising how white the fiberglass was! An orbital sander with 150 grit paper was used to prepare the entire hull for the first layer of paint, but corners and crevices were wet sanded by hand to prevent damage to the underlying fiberglass. A full respirator and safety goggles are highly recommended for this, as some marine paint dust is highly toxic. A box fan helped with visibility while I performed this task underneath the trailer. Areas where the bottom paint started to chip also required some scraping. All of this was followed by a washdown with some simple house siding cleaner.

The hull was painted in two sections: above and below the waterline. Paints used below the waterline are typically ablative (a.k.a. soft)—meaning that slowly the paint leeches a chemical that prevents the build-up of algae or other marine life. There has been a lot of legislation in recent years about what are acceptable marine paint ablative fillers—copper is most common and is the filler of the type of Rustoleum I used. Since this boat will be primarily used in freshwater, the ablative properties aren’t as important. However, since I didn’t know the type of the bottom paint I’d be painting over, and hard-coat paints don’t cover ablative paints well, ablative was my only choice.

The hull portion located above the waterline was painted first, and my wife was an enormous help here. She had the patience to precisely tape off the waterline, where the hull paint meets the bottom paint. When it came time to paint we used a topside Rustoleum. The wife primarily focused on the trim work while I rolled the rest of the hull. Painting the hull above the waterline was probably to easiest task of all and could be done in about 45 minutes.

Another round of sanding occurred after the first coat of paint, this time prepared with 220 grit sand paper. After a washdown, the next layer of paint was applied.

Outside of the obvious challenges of painting a boat on the trailer (cramped working space, fresh air, paint all over myself) there is also the issue of the trailer rollers. After the rest of the bottom had received the recommended two coats, I needed to roll the boat about 8-10 in. back on the trailer to paint the spots that had been obstructed by the trailer rollers.

Sliding a 1,500 lb. vessel on the trailer isn’t easy, so I deployed a car jack between the upward trailer post and the nose of the boat. After some fabric and wood bumpers were added the car jack was the perfect solution. I kept the boat in this position for about 24 hr., which was just enough time to fill in spots on the bottom of the hull.

This was also my opportunity to do a lot of other painting and aesthetic improvements, including the companionway hatch boards and steps, some areas of woodwork and repair on the interior, toe rails and several other spots that were faded or didn’t match the new color scheme. As one of the last acts of this phase, my wife applied new registration stickers.

And now she’s ready for a name. (The boat, that is!)

16 comments; last comment on 10/31/2017
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Could Driverless Boats Boost the Shipping Industry?

Posted August 10, 2017 12:00 AM by Hannes

Some critics believe the world shipping industry is struggling. According to the International Maritime Organization, over 90% of the world’s trade takes place on the seas. But shipping companies overburdened with outdated container ships are scrapping them for a fraction of what they initially paid, major shipping lines are going bankrupt, and profitability in the industry is weak.

These conditions might make the industry ripe for innovation in the near future. Specifically, the shipping industry could take a page from automotive developments and turn to autonomous ships to alleviate the profitability issues.

Rolls-Royce is leading the charge toward remotely operated vessels, projecting that the first one could launch in coastal waters in 2020. About a year ago the company released a YouTube video imagining a futuristic “command center” remotely controlling scores of ships around the globe. While it’s tempting to dismiss this excessively overengineered vision, autonomous shipping comes with some potential benefits. Eliminating a crew of 16 or 17 workers for every ship makes the whole process safer. Seafaring is dangerous work: according to an Allianz report, between 1996 and 2005 UK vessels experienced around 11 deaths for every 100,000 seafarers. That’s 12 times higher than the general UK workforce. Other countries were even higher: Poland and Denmark experienced 84 and 90 deaths per 100,000, respectively.

The Allianz report claims that 96% of maritime accidents are the result of human error, and AI advocates (like Rolls-Royce) point to the fact that unmanned ships would obviously eliminate the operator fatigue problem. Autonomous ships could also reap other benefits, like greater efficiency and eventually lower costs. But the Allianz risk report mentioned warns that an overreliance on technology could make shipping more dangerous. The report cites several instances of accidents caused by faulty GPS equipment, including the famous instance when the Royal Majesty cruise ship ran aground near Boston in 1995. In the case of a malfunctioning autonomous ship, an onboard human could override the technology, but doesn’t this defeat the purpose?

Like autonomous vehicles, though, nothing is truly black and white, so the industry could employ AI technology piecemeal or only for certain ships. GPS-enabled autopilot has been common for some time, so a more mature version of this tech could bridge the gap to full autonomy. And even industry leaders like Rolls-Royce know that autonomous ships are even further in the future than autonomous vehicles. Until then, no need to worry what you’d do if a 500-ton supertanker—without a pilot, no less—goes rogue on the high seas.

15 comments; last comment on 11/06/2017
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The Sailboat Diaries: Building a Bilge

Posted July 20, 2017 2:07 PM by HUSH

For what it’s worth, I’m several projects ahead of my blog updates. I just haven’t had as much time to blog lately as I would like. Let’s hope that changes in the near future. (Also, kicking myself right now for not naming this blog series Ship’s Log!)

The bilge of my boat is to scale for a ‘pocket cruiser.’ It is considerably shallow (between 1-1.5 in. deep), and isn’t much larger than the sole of the cabin (roughly 8 ft. long by 4 ft. wide). It’s a small boat and like many smaller sailing dinghies it isn’t usually outfitted with a pump. It acts like a basin for the occasional topside leak, rain ingress or dripping-wet swimmer. Sailors with this type of bilge will typically empty it with a sponge or small siphon once back on land or at the dock.

Yet there are a few reasons why I need to install a bilge pump. First, there is a small hull leak around the keel trunk and on my shakedown cruise last October it was enough to fill the bilge in an hour’s time. (Apprently she was waterborne for most of 2016 with that leak.) Even though I intend to fix this leak completely, the ability to evacuate water from a 50-year-old boat cannot be undervalued. Also, to find and fix the leak, I’m going to need to fill up the inside of the boat with water; eventually all that water will have to be pumped out.

Lastly, my state is quite strict about invasive species and all bilges must by dry before a boat can be launched in a new lake. Several law enforcement agencies inspect and regulate this heavily!

Ideally my boat will have two bilge pumps for redundancy’s sake, but for now one will have to do. I elected a manual design because I didn’t want to have another appliance drawing electricity and also because most electric pumps are submersible, and none (or quite few) would fit the very shallow dimensions of my bilge area.

The Boat Owner’s Association of the United States recommends a pump output of 450-700 gallons per hour for a 20 ft. boat, and using this as my guidelines I bought the Whale Compac 50 (for myself, for Christmas, back in 2016).

Installation started by drilling a 3-3/8 in. hole into the storage locker underneath the port side quarter berth. I selected this location because it provided ample space to stroke the pump and also observe the bilge level from the cabin. The bilge gasket and deckplate installs on the outside of the locker and a removable handle ensures a clean aesthetic when the deckplate is closed. Installing the pump in the locker was painful because there are four screws the needed to be blind-threaded from the deckplate into the pump. After two hours and some blood loss I eventually got it aligned and tightened.

Bilge exhaust plumbing requires a mechanism known as a vented loop. This mechanism prevents water from siphoning back into the boat should the bilge exhaust ever find itself submerged. This is perhaps a little bit overengineered because my bilge exhaust is above the waterline and the manual pump should prevent water from siphoning all to way back into the bilge (which should only potentially happen on trailer launches and haul-outs). On my Matilda, the vented loop is positioned high along the inside transom wall, not far from the repair shown in Fiberglass-By-Numbers. It was screwed into a painted piece of wood that is epoxied to the fiberglass.

The 1 in. diameter pump intake hose runs underneath the boat’s kitchenette(-ette?). The sink currently drains right into the bilge so I ran the hose alongside that drain line, but continued the hose underneath the cabin sole. The end of the intake hose has a plastic screw-in strainer. The pump output, also 1 in., runs along the locker area before it has to extend underneath the cockpit floor so it can meet the vented loop. The loop is connected to a 90° stainless steel through-hull located on the upper starboard side of the transom. The hose connections are held tight by hose clamps, while the through-hull was secured with some 3M 5200 marine sealant and a plastic nut.

Today, I’m happy to report that my Matilda can expel water whenever she needs to.

Other completed tasks:

  • Installed six vents around the cabin and cockpit to increase airflow in storage lockers
  • Replaced all hardware on rudder assembly
  • Installed new tiller
  • Painted bilge cover boards

7 comments; last comment on 07/25/2017
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