Donald Crowhurst Movie Update

Clark April 19th, 2017

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My original announcement of the movie is here. There has been little news since, but the production company has thrown us a few bones:

1. It’s actually happening! There is going to be a mainstream movie about Donald Crowhurst and the 1968 Sunday Times Golden Globe Race, starring Oscar best actor winner Colin Firth as Crowhurst, and Rachel Weisz as Clare Crowhurst. This is likely to be the biggest movie ever made about sailing, or at least sailboat racing. They couldn’t have chosen a more fascinating and portentous moment in our sport.

2. They released the photo above. That’s it. That’s the teaser. A still of Colin Firth, as Crowhurst, looking worried aboard the re-created Teignmouth Electron. Read into it what you will.

3. The title of the film is The Mercy.

Beyond that they just say it will be released in 2017 sometime, and I will be the first in line.

Here is the story in the Hollywood Reporter.

Metal Tank Repair with a Shop Vac

Clark April 12th, 2017

One of my boat’s stainless steel water tanks has always had a hole in it, and a series of patches, the last of which held for twenty years, until it failed last week. Here are the tanks, under my floors and settees, meaning replacing them is out of the question, or at least worth a lot of time futzing with patches:
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After circumnavigating for ten years on an old boat with not only a water tank with a hole in it, but steel fuel tanks with holes in them, I’ve developed a more nuanced approach to patches. I made it over three years with the bottom of a fuel tank patched with JB Weld, a fortified epoxy product. I’ve had very good luck with small repairs with JB Weld, and I always keep some aboard:
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Obviously if you get into bigger repairs where some structure is needed, regular liquid epoxy, fillers, and fiberglass are better, although I’ve also had good luck with small pieces of fiberglass impregnated with JB Weld. Point being, patches, done right, can be very solid, adding years to the lifespan of a tank, or at least getting you to your next port where a replacement, or welded repair, can be made. But the patches have to be done right, not rushed, with meticulous attention to detail.

Back to my water tank. Here is the part with the leak, and the leaky patch in place:
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Here is the entire patch coming off in one piece, which tells me that epoxy doesn’t stick very well to stainless steel, even if it did last twenty years:
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On to the shop vac and my more nuanced approach to repairing leaks. First, empty the tank, or at least get it well below the level of the leak. On most shop vacs you can attach the hose to a different orifice and turn it into a blower. Turn it into a blower and attach the hose to the tank. Some tank testing procedures call for pressurizing with compressed air up to 3 PSI, but we don’t need to go that far, just enough to force a little air out our leak(s). Here I’ve got the hose loosely attached to a tank fitting. I didn’t need to close off the vents, tape it, or take any other measures:
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With the tank pressurized I could go around with soapy water, looking for bubbles and pinpointing my leak:
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It turned out to be an invisible crack in a weld, about half an inch long, visible with a mirror, or by shoving my iPhone down there:
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Now that I’d precisely located my leak, rather than slathering a whole corner of the tank with epoxy, I could pinpoint my repair. As anyone with a boat knows, tracking any kind of leak can be very frustrating. General wetness, be it water, fuel, oil, or whatever, is never a precise indication of where the problem lies.

Sand, sand, and sand some more. You want to key the metal as deeply as possible to give the adhesive something to bite into. I was going to go at it with a 16 grit disk on an angle grinder, but I couldn’t fit the angle grinder, so I sanded by hand with 60 grit. With metal, you must make it bare and shiny. On steel you may get to bare shiny metal, but still have some black spots. These black spots are rust seeds, and they will grow into rust trees and destroy your patch, or lift up your paint if you’re painting. The black spots must be removed. With aluminum, remember that the surface oxidizes minutes after sanding, so move quickly. Bare, shiny metal.

Now it’s on to three things, in whatever order works:

1. Heat the area with a heat gun or torch, enough to cook the moisture out of the crack or hole, and dry the inside of the tank:
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NOTE: If you’re repairing a fuel tank, don’t use a heat gun or torch! Welders insist that there not even be a whiff of fuel smell – gas or diesel – before welding a tank. If there’s fuel present, might opt for a day of drying, compressed air, or some other method to dry it out.

2. Switch the shop vac to suction mode and put the whole tank in suction.

3. Clean the area with acetone. When metal looks shiny and clean, it’s still dirty and greasy, so keep cleaning with acetone and fresh paper towels until your paper towel comes off spotless:
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If no fuel danger, mix your epoxy or JB Weld, keep the tank in suction, and keep it hot. At 140 degrees F you can keep your hand on metal for about two seconds before having to move it. This is about right. You don’t want to fry your epoxy. Heat will lower the viscosity of your epoxy and let it flow better, so that with the warmth and the suction, some of your goop will be drawn to the inside of the tank, or at least into the crack or hole. By keeping it warm and spreading it thinly, I could see with a mirror as the JB weld dimpled into the crack.

Turn the shop vac off and slather your patch area on the outside.

Obviously if you can get to the inside of the patch, clean the inside to bare metal and attack from both sides. This was the case with the patch in the bottom of my steel fuel tank, the one that lasted three years, until I got new tanks. On my water tank there are baffles in the way.

Four hours later, after the first layer had begun to set, I laid on a second, wider layer of JB Weld, just for good measure. The next day I filled my tanks, and my bilges have since remained dry:
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I think the shop vac makes a big difference, of course combined with meticulous prep work and cleanliness. By pulling material into the leak you’re repairing the actual breach and keying some material into it, rather than coating over it. When you just coat over it you’re relying entirely on the adhesion of the goop to bare metal. I’m guessing this patch will last another twenty years, or more, and if any other small leaks crop up I’ll go through similar exercises many times before I consider the huge expense, and gargantuan task, of replacing the tanks.

Charge!: Chargers, Plugs, and Receptacles On Boats

Clark March 27th, 2017

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The cigarette lighter plug/receptacle has long been the de facto standard to connect portable 12-Volt devices, and it sucks. Nobody smokes anymore. It’s bulky, insecure, makes poor electrical contact, and can’t carry high current. It’s got to be the only electrical connector in the history of electrical connectors with a compression spring that is constantly trying to break the connection.

I suffered many a night when the only difference between a good sleep and waking up in a pool of sweat, ravaged by mosquitoes, was a 12-Volt fan plugged into a cigarette receptacle above my bunk. If I so much as twitched, it disconnected. If the boat rocked it disconnected. It spontaneously disconnected, because the little spring was always trying to push the plug out of the receptacle. And this was with a stainless steel receptacle from West Marine and a Marinco plug, both purveyors of quality marine equipment.

The receptacle above my bunk looks all marine and stainless steely, but it wants to spit out plugs:

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We’re stuck in this backward compatible nightmare simply because cars started coming with cigarette lighters way back when. There has to be a better way. Some enterprising company has to invent the better mousetrap, sell it to the world, and commit to it for twenty years or so, long enough for the world, or as least us boaters, to banish the cigarette lighter receptacle forever. Blue Sea Systems? Marinco? Cole-Hersee? I’m calling you out!

Currently there’s just not much out there to adopt, even if we all agreed to lop off all those cigarette lighter plugs and make a collective switch. There are lots of good in-line connectors (connectors that connect two pairs of wires together), but we don’t want some pigtail hanging out of our nav station: We want a streamlined, sexy little receptacle.

The closest thing I’ve found is the EmPower plug/receptacle, used on some airlines. It’s 15-Volt DC (close enough to 12) but limited to 75 Watts, and 75 Watts at 12 Volts is only 6 Amps, and that’s not much. I’m guessing the connector itself could take much more, but the in-flight systems limit it to 75 Watts so you can’t actually charge your laptop, which is apparently a fire hazard at altitude. Anyway, the EmPower plug/receptacle is barking up the right tree:
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Some features this future dream receptacle and plug should have:

1. Compact: It can have a way smaller footprint than a cigarette lighter receptacle and the plug shouldn’t stick out nearly as far.

2. Polarized: Can’t be any way to plug it in backward and reverse the polarity.

3. Rated for 20-30 Amps: Should be able to plug in a 450-Watt portable inverter and have it work.

4. Secure: Yes, but don’t need to go overboard. I think a home 110 AC plug/receptacle is about right in this regard: You can vacuum the whole room and shake the cord every which way and the plug won’t pull out of the wall, but if you accidentally roll the vacuum cleaner down the stairs the plug will pull out. I don’t think there needs to be a locking mechanism, per se, as with a shore power cord, but if you’re using a plug-in spotlight in full combat mode, it shouldn’t come loose when you move about the cockpit (another personal pet peeve).

5. Circuit protection?: I say no. Many cigarette adapters have a fuse in the plug, but this isn’t the place for circuit protection. There’s not a circuit breaker in the plug for your toaster. The circuit supplying the receptacle should be protected by an appropriately-sized fuse or breaker, then any further protection should be in the device itself.

6. Easy install/adaptation, especially for the plugs: Installing the receptacles can take however long it takes, but installing the plug on a new device should be quick and easy. This way, if some of us are are to adopt this new dream connector and ditch our cigarette receptacles, and we buy some new device that comes with a cigarette plug, it should be a joy, rather than a chore, to lop it off and replace it with one of our dream plugs.

Anything else?

Back to reality and what we’re stuck with. Marinco and Blue Sea Systems make the only cigarette receptacles/plugs worth their salt. They’ve taken lemons, and made lemonade, so to speak. I have several of them aboard, and they really are better. The receptacles themselves are superior, in and of themselves, but used with their plugs it’s the best deal going. The plug twists and locks – sort of – into the receptacle, and at least holds the spring in compression and prevents unintended disconnects. Not cheap at about $30 for a receptacle/plug combo, and another $15-$20 for additional plugs:
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It’s worth having at least one of these receptacles, then the corresponding plugs for your mission critical devices. For me these are the portable inverter, the spotlight, the fan, and a 12-Volt vacuum cleaner.

USB connectors are now ubiquitous for charging all kinds of devices, and powering a few, but USB operates at 5 Volts, so forget about powering 12-Volt devices. Still, it makes sense to install one of the marinized USB receptacles for phones, iPads, and the like. Without one you’re looking at additional adapters and claptrap, or running an inverter, just to charge a phone:
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Or one of these combination panels, with the cigarette receptacle and the USB ports:
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They sell combination AC outlet/USB sockets, so if you’re running AC all the time this is kind of nifty. I installed one at home, and it cleans up our charging station somewhat. We just need the cords now, without the adapters:
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Eight Bells: Bill Ficker

Clark March 21st, 2017

I received sad news from my dad last night that Bill Ficker passed away last week. As a racing skipper, Bill won both the America’s Cup and the Star Worlds. For those of us who know what that means, enough said.

I knew Bill, through my dad, my whole life, and I’d see him at my dad’s coffee klatch when I visited. At this coffee klatch, which didn’t have any slouches when it came to sailing, Bill was always the alpha dog, yet patient, unassuming, and shy about his accomplishments. The last time I saw him at the coffee klatch he said, “If nobody has any more questions or problems that need solving I’ll head out and start my day.” I must have looked blank, and my dad said, “You know he’s completely kidding when he says things like that. He’s known all of us for over sixty years.”

Story here in the Daily Pilot/LA Times.

V-Berth Rebirth (with strong opinions about drawers on boats)

Clark March 20th, 2017

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Like many V-berths, mine was designed to be two bunks, but by putting a board and a cushion between them it becomes a double berth. Since the cushion in the middle is called a keystone cushion by the upholstery people, we’ll call the board the keystone board.

On my boat the keystone board and cushion are in place nearly 100% of the time, creating my captain’s cabin, roughly the size of a queen-sized bed. Below the keystone board is seldom seen, but this is some primo storage, accessed from aft, and visible looking forward from the main cabin. During my circumnavigation it was home to my bike and my guitar. In the photo above it is occupied by a shop vac, and a baby lies on the keystone cushion.

Recently I cleared out the V-berth to replace the opening ports, and upon seeing below the keystone board for the first time in years, decided to gut and rebuild the V-berth.

First, though seldom seen, it’s all unsightly. The teak veneer is peeling off the plywood, and once plywood gets to this point there’s not much to be done for it cosmetically:
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Second, below the keystone board, on both sides, are a drawer, a cabinet, and a cubbyhole, none of which are accessible with the board in place and the bed made up:
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The cabinets are innocuous, but the cubbyholes are useless, and the drawers are a complete waste of space. I did away with the drawers long ago, keeping only the drawer fronts, fastened from behind:
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Drawers are never an efficient use of space on a boat, but of course they’re the best for convenience. A boat should definitely have a few drawers around, especially in the galley, but anyplace you put a drawer you’re giving up some overall space in exchange for that convenience. Drawers are square and boats are round, so a drawer never takes full advantage of the volume it occupies. Then add all the support structure a drawer requires, and you’re probably looking at halving, or worse, the volume of a storage space by subdividing into drawers. In my V-berth, for example, the large, deep compartments under each berth were completely blocked off – interrupted – by the drawers and their supporting structures.

I found while cruising that larger storage spaces, big enough for a sail or an outboard motor, were the hardest to come by. Smaller items can always find a home. By ripping out my drawers I opened up some big new storage spaces, but they could only be accessed from above, meaning moving a mattress and bedding.

Finally, they say with fiberglass boats of certain vintage they built wooden boats inside of fiberglass boats. This was especially true at the foot of my V-berth, the forward part, where they’d built a wooden boat inside a fiberglass boat, then changed their minds and did it a second time inside the first, then threw in some fake bulkheads and terrible access. This was the only entry:
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By gutting it and rebuilding it this:
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…was replaced by just the two unpainted beams running athwartships, opening about two cubic feet of previously-unused storage space:
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So my new design would have no drawers, cabinets, or cubbyholes. The only access to the storage would be from above, from under the bunks, but I’d want plenty of ventilation, so I put in five of these round vents:
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Finally, the boards under the bunks didn’t allow for very good top access, since they assumed the whole space would be occupied by the drawers. I made templates and then cut new boards from a sheet of half inch marine plywood. I think it’s a good idea to have lots (6) of smaller boards for access, rather than fewer larger boards, and to divide starboard from port so you can open the bedding like a book and get to one side of the storage. It would be tempting to have the boards at the foot of the bunk (forward) be one piece, but then you’d have to move, or bend up both mattresses:
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I made the aft boards the smallest, so I can get to them from a standing position, while lifting up the head of one mattress:
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Of course I varnished all the new work and everything else in there. I spray painted all the headliner panels years ago. It was time to do it again:
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You’ll notice I didn’t show you the final product with the cushions back in place? That’s because the cushions are also fifty years old, but that’s a project for another day.

Marine Carpentry for Dummies

Clark February 23rd, 2017

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To be a true marine carpenter is to live in the high country of the craft, because boats are curved every which way. There is seldom a right angle, seldom even a simple beveled angle, because all those intersecting curves mean that every place two pieces of material join together is a compound angle. To put a finer point on it, terrestrial carpenters can frame a four-bedroom house in a day or two. A team of talented marine carpenters can frame a 40-foot wooden boat in a couple of months? A couple of years?

I am not a marine carpenter, but I often get into marine carpentry projects, or more accurately marine joinery, like building new electrical panels out of teak, rebuilding consoles, and of course endless work on my own boat. I have many more tricks to learn, but here are a few rules I’ve picked up:

Thou Shalt Measure Angles

To make a piece with a compound angle, a tape measure is only going to get you so far. You need some way of measuring angles accurately, then you later replicate these angles to your cuts. I haven’t found a great product for measuring angles in tight spaces, but this protractor is what I’ve got, and I can always make it work by turning it one way or another:

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The important thing is to be able to measure accurately down to the degree, because if you’re off my more than a degree in finished joinery it’ll stand out like a sore thumb and reveal that you are a hack.

Thou Shalt Draw Diagrams

All the angles and measurements you take will only lead to confusion unless you document them and get them to the cutting area without reversing something. Overcommunicate with yourself: Note top, bottom, inside, outside, port, starboard, forward, aft, athwartships, all the lengths, and all the angles, and you’ll still manage to screw something up:
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Thou Shalt Make Templates

There may be master marine carpenters out there who just go take their measurements, then cut perfect finished pieces, but I doubt it. Everyone I’ve seen makes lots of sacrificial templates, these templates go through multiple rounds of tweaks, and end up with hieroglyphics scrawled all over them.

Good quality teak runs $30 to $40 per board foot. A board foot is a foot wide by a foot long by one inch thick. A sheet of 3/4-inch teak-fronted plywood is $220 where I buy it. Ergo, mistakes become very expensive. This piece of trim I’ve installed in a head is over a board foot of teak, and it sure don’t look like much:
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For trim pieces I make templates from cheap, usually scrap, plywood of the same thickness:
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Simply mock up your measurements and diagrams in cheap plywood, then go try them out. Of these four templates, one ended up perfect and the other three needed tweaks. I purposely make the templates a little short, which means I accidentally made one too long and it ended up perfect…by mistake. By making them a little too short, say by half an inch, you can fit your template in place (if it’s too long it can’t even fit), and ensure that the angles are all right by sliding it from side to side. If not, you can measure much more accurately now that you’ve got something to go from, and make notes on your templates. You can also now get your final length measurements very accurately, since you’ll be increasing the length of your template by some fraction of an inch, rather than relying on overall measurements.
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I guess this is just another way of saying I know I’m going to make mistakes, so if I make mistakes on purpose I feel better about myself. There are two other reasons for cutting your templates too short: First of all, those overall length measurements get very confusing with a piece that has compound angles on one or both ends. Do you mean the length at the inside corners, the outside corners, top, or bottom? These will all end up being different length measurements. Ideally you want your length measurements based on where the saw blade will enter the material, rather than where it will exit, as the entry point can be measured and marked very accurately, while the exit point is only known for sure when, well, the blade is finishing the cut.

Second, due to that pesky fact that boats are curved every which way, your piece will probably have some bend induced into it in final installation, and with a template that’s a little short you can bend it into place and see how this bend changes the angles. Unfortunately plywood is more flexible than hardwood, so there may be some surprises in the final installation due to the different properties of the two materials, but these surprises are usually minor.

For larger panels, to be made out of plywood, there are several 4 x 8 foot sheet products, such as hard board and utility panel, that cost less than ten bucks per sheet. Make templates, and your mistakes, on these. Once you’ve got a template for a larger panel, even if it’s way off, it can be made perfect by stapling, taping, or hot gluing extensions here and there, or cutting off excess material with a saw or utility knife. I discuss how to be gentle with veneered plywood here.

These cheap template materials are usually thinner than the final product, and this sometimes leads to some unpleasant surprises too. If you’re making a really complicated piece out of plywood, best to make the template out of the cheapest plywood you can find of the same thickness.

Thou Shalt Have a Good Way of Cutting Compound Angles

If you’re building something like the trim for this instrument cluster, count yourself lucky. It’s all right angles, and the pieces are so small that mistakes aren’t terribly expensive:
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I’ve had this simple hand miter saw for years, which makes accurate angled cuts, and the blade has stayed sharp through countless pieces of teak, but it can’t cut compound angles unless I use some cockamamie method with shims:
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To cut compound angles you need either a table saw with a crosscut sled (miter attachment), or what is called a compound miter saw or chop saw.
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In other words, you need a way to accurately cut angles, and accurately angle the blade while cutting said angles. Of the two, a chop saw is way cheaper. I’ve seen them for as little as $100, but can’t vouch for quality at that price. A chop saw is the better machine for trim work, for pieces less than six or eight inches wide, but to make long, straight cuts a table saw is king. A chop saw can be stowed away on a shelf; a table saw needs its own room.
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A handheld circular saw is great too, and can cut both compound angles and long cuts, but it will never be a precise as a chop or table saw.

When preparing to make your final cuts on your final material you can set the angles on both the miter and the blade angle, then cross-check these angles with your protractor and your template. Use a fine-toothed finishing saw blade to avoid splintering, and clamp your material where possible.
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Thou Shalt Not Try to Correct Your Mistakes (Too Much) By Sanding

It just seems like you can nip off that extra material with your belt sander and it will fit perfectly, right? It won’t. It’s nearly impossible to square up an angle by sanding. Sanding always rounds off the edges and leaves the middle too proud. By all means clean up the splinters and rough edges by sanding, but you’ve got to get your angles right with the saw.

Split Your Angles

If you measure a 110-degree angle where you want a miter joint between two pieces of material, each piece needs to be cut at a 55-degree angle. If you make one 35-degrees and the other 75-degrees it won’t work and it’ll look funny.

Shape Your Pieces Before Cutting

Your pieces will undoubtedly be shaped, with rounded corners, or in the extreme quarter-round or half-round material. If you cut your pieces from square or rectangular material first, then shape them afterward, it will be hard to make the miters match. If you shape your whole piece of material first, then cut the miters, it will still be hard to match the miters sometimes, but you’ll be off to a better start.

It’s very satisfying when you get it just right:
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Advanced Electrical: Diodes

Clark February 7th, 2017

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The most common diodes on boats these days are LEDs, Light Emitting Diodes, which are changing the way we light our boats and use energy. They’re great! There are all kinds of specialty diodes in the electronics world, but the kind of diodes I’ll discuss here are basic, simple old diodes, the kind you could buy at Radio Shack for thirty-five cents, if Radio Shack were still in business. I always keep a few diodes in my box, because they provide a magic solution to some very specific problems.

Diodes are one-way valves for electricity. Place a diode along a wire and electricity will flow one way down the wire, but not the other. If you connect an LED the wrong way it won’t light up; connect it the proper way and voila. Above is the electrical symbol for a diode, and as you might guess, the arrow points in the direction of current flow. Current can’t flow against the arrow.

It’s good to know the symbol, and basic symbols for switches, fuses, and the like, because when considering a diode to solve a problem, diagramming the circuit first really simplifies the matter. An actual diode looks like this, and the silver band is the cathode end, that is, the end the current flows out of, but not into:
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There are several common situations when I use a diode on a boat. The first is when I’m installing a light like this:
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It’s got a bulb in front, and one in back. When you want it to be an all-around light, or anchor light, you power both; when you want it to just be a steaming light you only power the front bulb. Sounds simple, but it’s not so simple. Since the the two bulbs share a negative wire (three wires, not four, lead into the assembly) you’ll quickly find it’s hard to separate them: Both bulbs will light together when you only want the steaming light.

The simplest way to avoid this is by using a DPDT switch (Double Pole Double Throw), a switch with ON-OFF-ON settings and various terminals for isolating the various loads. Turning this switch to one of the ON positions gives you your all-around light; turning it on in the other gives you your steaming light, maybe along with the nav and stern lights. But sometimes this setup isn’t practical, and many electrical panels come with one switch for an anchor light and one switch for a steaming light. Enter the diode.

By placing a single diode in this circuit you can make your two switches do what you want them to do:
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If you follow the circuit you can see that without the diode, unintended current would flow from our steaming light circuit to our anchor light circuit and make the aft bulb light up too. If, in the same circuit, we had nav and stern lights connected to our steaming light switch, then they’d light up when we turned on our anchor light. A second diode would prevent anchor light current from flowing to our nav and stern lights.

Another common use for diodes is for engine alarms. The standard setup is to have a light/buzzer that goes off when you’ve got high water temperature or a drop in oil pressure. Well, which is it? It would be nice to know at a glance whether the alarm is from high temperature or low oil pressure, and to have a separate light for each. Depending on the way the panel is wired, you’ll sometimes get the same problem as with our pole light, both bulbs lighting when you only want one, and a diode can isolate them.

Electricity can be sneaky, especially on engine panels and distribution panels where you’ve got a lot going on in the same place. Sometimes, even in a well-designed and well-built panel you’ll get a sneaky phantom current that makes bulbs glow dimly or buzzers/beepers make irritating noises. Again, simple placement of a diode can solve the problem without completely dissecting your handiwork.

Also found on boats are solar panel blocking diodes: Solar panels “leak” a bit of juice at night, so the blocking diodes prevent this back flow. Solar blocking diodes (indeed all diodes) add some resistance to the circuit, reducing the panel’s output somewhat, so the day/night balance ends up being about a wash.

Basic diodes usually have four different ratings, most of which can be ignored for our purposes. I always use NTE5800 diodes, which are rated for up to 3 Amps of current. I know I’m never going to have more than 3 Amps, because I’m always solving problems like those above, with small bulbs, buzzers and the like, in 12 or 24-Volt DC systems.
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The NTE5800 diode takes .9 Volts to “turn on,” that is, to function, and I’m always going to have that in a 12 or 24-Volt system. It’s rated at 200 Amps to break it, that is, the amount of reverse current to make it fail and not block. 200 Amps ain’t gonna happen either. It also has other ratings for the amount of abuse it can take in either direction before it fails, but these aren’t ever going to happen in my applications. I just need to remember it’s good for 3 Amps, and if I ever try to do something exotic I might need a different diode.

In practice I like to install diodes using two heat shrink butt connectors to connect the diode’s two leads to wires. The leads on the diode are live and exposed, so I always then cover the whole thing with heat shrink tubing, both protecting from accidental shorts and waterproofing it (I think they’re waterproof anyway). Then definitely label it on the outside with some kind of label (white heat shrink tubing works well), otherwise it will just look like a mystery blob inside some heat shrink tubing. It’s also very easy to bend the terminals on the diode, insert them into two of the terminals on a screw-down terminal block, then connect your wires to the opposite terminals.
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Vendée Globe Nail Biter

Clark January 18th, 2017

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If you haven’t been following it, the leaders in Vendée Globe are within a day or two of finishing, to cap one of the greatest games of cat and mouse in sailing history. At the time of writing, after racing for 73 days and over 24,000 miles solo, Alex Thomson is only 34 miles behind Armel Le Cleac’h.

Alex Thompson has slashed the gap by two thirds in the last few days, in part by setting the Vendée single day record. Video here. You will also see in the video that Mr. Thompson is battling multiple equipment failures, but still fighting to the end.

Thompson acknowledges that it would be tough to win at this point (yet he keeps closing the gap!) Full story here. He’s been up for days, and is on the verge of collapse.

At any rate, in the next 48 hours we’re going to see either:

1. Thompson overtakes Le Cleac’h to be the first non-Frenchman to win the Vendée Globe. In this scenario, could the Vendée Globe get into close tactics? Le Cleac’h luffing Thompson up as they turn off the autopilots a go into full close battle mode, when neither have slept in days dodging fishing boats and freighters, hallucinating at the wheel? Unlikely, but would be something for the record books.

or

2. A very close finish, in which Le Cleac’h crosses the finish line, then just has to wait an hour or two to embrace the man he has battled all the way around the world. The two have thought about each other every moment for 75 days, yet haven’t see each other’s faces since the start. When they finally meet face to face, it will be a moment to remember.

3. Or some crazy thing we never could have foretold…

Ways to watch it are here.

Electrical Fire! (and some lessons learned about starters)

Clark January 2nd, 2017

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Voice Mail: “Hi Clark, it’s (name withheld). I was out sailing today with my daughter and we had an electrical fire on the new starter you installed. Because of the fire we lost the engine and hit the south tower on the Golden Gate Bridge, called the Coast Guard, and had to be towed back to our berth. When I opened the engine compartment there were six inch flames rising from the starter, but I was able to blow them out. I don’t know where that leaves us, but I’d sure like to speak with you.”

Not what a marine electrician wants to hear. After my initial panic, I reflected that this was a basic R&R (remove and replace) of an old starter for a new one. I’d tested it several times, by cranking and starting the engine, and all seemed well. Various scenarios flew through my mind – defective starter, defective solenoid, some sort of shorted wire, stuck solenoid or stuck starter button, or, eh gads, installer error. I called the owner, who was very understanding, and was back on his boat the next day. If you look at the photo above, all the insulation on all the wires leading to the starter is fried, and was burning until he blew it out.

After an initial check, I called the owner and told him that no matter whose fault it was, the damage was probably less than the deductible on his insurance, and that I might as well remove the starter and start the replacement process. He agreed. I pulled the starter and found it well-burnt, and the solenoid completely melted, with both of the studs loose. The main linkage between the solenoid and the starter motor had acted as a fuse, melted through, and ended the fireworks:
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I took it back to the starter store, where they were very understanding and agreed to replace it under warranty, but also opined that something had probably got stuck, and that the starter probably wasn’t at fault. They noted some damage to the pinion gear, which I hadn’t noticed.

I installed the (second) new starter and continued my postmortem, finding very quickly that the cranking circuit was closed, as in, if I’d connected it the starter would have started cranking and wouldn’t have stopped. In this instance the boat had a starter button, separate from the key switch that energized the circuit, and the button was stuck:
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Blessed sweet mother of God, it wasn’t my fault! I replaced the button, and the burnt wires, tested it all out, and all was well, for the second time. The owner was very understanding, ended up buying my wife and me a nice bottle of wine, and we decided we owed the guys at the starter store a case of beer.

There are some interesting things that happen with a stuck starter, one of which I didn’t know about. I knew about shorts, of course, and 98% of high amperage starter circuits aren’t protected with fuses, so these can be spectacular. And I knew about all kinds of unintended open circuits, as with bad motors, bad solenoids, etc. But I always thought that a stuck starter, as in, a starter that stays engaged after the engine starts, would just burn out its innards or strip its pinion gear.

Nay. A starter that stays engaged after an engine starts gets spun continually, much faster than its intended rotation speed, and actually becomes a generator, sending high current back into the electrical system. In most cases the batteries and cabling can handle the current, but the starter can’t. It gets very hot and finally burns up (from high current, rather than friction, overheated brushes, or whatever). Even in normal use a starter is an intermittent duty motor: With a recalcitrant engine you should only crank it for ten seconds or so at a time, then give it thirty seconds to cool off, and to allow the surface voltage to come back on the battery.

So, it is very important to make sure your starter disengages after your engine starts. In most cases this is obvious, as in your car, where if you held the key in the cranking position, or the starter got stuck this way, you’d hear it. But on many boats it’s not so obvious, since the engine panel might be some distance from the engine, and once started the engine noise can drown everything else out.

This boat happened to be a Catalina, and on Catalinas it’s standard to have a starter indicator light on the instrument panel. This is a good feature, and not common on other boats, but you’ve got to know it’s there:
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On this boat it was there and still worked, but the owner didn’t know about it, plus it’s hard to see in daylight, and easy to miss in full combat mode (they were close to the south tower of the Golden Gate Bridge in an outgoing tide, after all). But also on Catalinas, and many other sailboats, the engine panel is exposed to the elements in the cockpit, sometimes gets kicked a lot, and generally takes a beating. In this case the starter button saw constant rain and spray, and eventually corroded and got stuck.

On my boat I’m standing right over the engine when I start it, so I’d hear it in a nanosecond if my starter got stuck, but not so on many boats. If it wouldn’t be obvious to you if your starter got stuck, you should consider an indicator light or buzzer. When you consider that it would result in not only a destroyed starter, but in not being able to start your engine again, and maybe an electrical fire, it’s worth some thought.

Shore Power Cord Economics

Clark December 13th, 2016

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Unfortunately, as in the photo above, the connectors on shore power cords often get toasty. It always seems to happen on the neutral connector (white wire in the US system) and I don’t know why. Maybe the electrons get all gummed up and dirty from being on your filthy boat, then get stuck on the way off?

Sometimes it happens on the male side too, and the guts of the shore power inlet have to be replaced:
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At any rate, a burned/melted shore power cord is bad, and should be repaired, but therein lies the rub. The new connector for the end runs about $35, but that’s not all. In order to make it like before you also need a new boot, which you can buy with or without the threaded ring, but call it another $15:
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So now we’re up to $50 (prices vary, but you get the idea) in parts alone to repair a shore power cord. Fifty foot, 30 Amp shore power cords sell for as little as $80, if you shop around. It’s fairly straightforward to re-terminate a shore power cord, which a do-it-yourselfer can easily do. It takes me about ten minutes, but it’s easy to see that the cost of parts, plus the cost of a marine electrician quickly makes the cost about a wash.

To do it right you’ll want some good wire strippers, a cable stripper (judicious use of a box cutter will suffice), a cutter big enough to lop off the whole fried end cleanly, then it’s nice to have a multimeter or AC tester to check that you haven’t reversed something that will really make things burn. So the task becomes daunting without all the proper tools, and if you don’t have the right tools they’re not cheap.

So what are we to do? It’s terrible that we live in such a throw-away society. I once toured the second largest open pit copper mine in the world, in southern Peru, and it’s no small feat to get copper out of the ground and turn it into copper wire:
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So alas, if you just need to replace one end of a 50-foot, 30 Amp cord, repair costs enough less than replacement that you should fight the good fight and do it, if you can do it yourself or your electrician happens to be around working on other things anyway. If you have to replace both ends it’s cheaper to just buy a new one. If the whole cord is looking fairly tired and sun-baked, then definitely replace the whole thing.

If it’s shorter than 50 feet, it’s probably not worth repairing it.

For 50-Amp cords the whole magilla gets much more expensive for either repair or replacement, but the economics are about the same.

Copper wire should always be recycled, but finding where to do this can be a pain. As a marine electrician I take a big box to be recycled every year. Back during the height of the economic crisis people were desperate and copper prices were at an all time high, so shore power theft was common.

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