Laying a Second Anchor

Rev. 7-22-2024.

 ( One of many draft posts as I was trying out ideas for my eventual book, "Rigging Modern Anchors.")

 For the most part, a single working anchor is a simple and dependable practice; nothing to tangle, a simple procedure, and since others do the same, boats will generally swing the same way in response to wind and current. However, on a holiday weekend you may find somebody has dropped way to close and you want to limit your swing in that direction. You may find that your boat swings differently from the others. The bottom may offer terrible holding; thin stilt over rock-hard clay is a common Chesapeake "bad" bottom; it feels like you have a set... until you pull, whereupon in tracks through the silt but refuses to go deeper and cannot be depended upon to reset in a shift. Severe storms may be coming and perhaps you are anchored too darn close to rocks to tolerate any dragging. Perhaps other boats moved in around you (herd mentality), restricting swing in one direction. All of these coincided  for us yesterday.

The greatest hassle of setting two hooks is the resulting tangle if the boat spins. If both are lowered from rollers, with the rode passing through a hawse pipe and  ending deep in the bilge, the twists are not easily removed. A simple solution:

I have since dispensed with chain, using a Dyneema leader with a webbing chafe cover. Reducing weight on the shank helps the light weight anchor to set.

• Get a light secondary anchor. I've been using Fortress anchors for this purpose for 15 years and love them. I've never had one drag.
• Do Not keep the second anchor on rollers. We keep ours in a stern locker, from where it is most often deployed. The rode lives in a bucket
• Keep the rode short; only enough for the day's situation. We keep 50 feet of rode on the anchor for most uses (in 6 feet of water with a 15 foot bridle this gives 7:1 scope). If we need more, we have two docklines with spliced loops in the both ends that we chain together with cow hitches. But only deploy enough for the exact scope you want.
• Connect the second rode either to your bridle or to the main rode a few feet below the bridle. We typically connect the second rode to the bridle plate with a strong stainless carabiner, but a Prusik hitch is good too.

Because the second rode is not connected to the boat, only to the rode, it is simple to disconnect and unwind if the boat has spun.

 A second anchor can actually increase the strain on the anchors, if the angle is too great. The optimum angle for holding is almost always 90-120 degrees; less, and the anchors will still need to reset when the wind shifts, more and the tight-rope effect really piles up the force in a cross wind.  The notion that 2 anchors set close to each other can increase holding is plainly false; even a small wind shift places all of the load on one, and the potential for the second rode to foul the primary anchor is too great. The case that tandem anchors provide increased holding is very weak, though it has proponents. The problem is re-setting; the second anchor will generally keep the primary on it's side, preventing a good bury, and 150% of  standard rode length is required (the second anchor "lifts" the rode by providing tension from the end of the rode).

Generally we use this procedure:

• Set the first hook at longish scope (14:1) and set.
• Lower the second hook from the transom, bringing the rode forward outside all of the rigging. If I had a heavier anchor I would mount a roller on the stern. This would also make it easier to load into the tender, when that is needed.
• If we are in shallow water, I can generally feel the hook in with that 35 feet of scope. If not, we shorten the primary as need to get in the right position.
• Take in the main rode to desired scope (7:1?).
• Give the secondary hook a better pull, just feeling it in.
• Connect secondary rode to the primary as above. Let at least 4 feet of chain out, so that if the boat spins, the chain absorbs the twist.
• If you're really expecting a blow and want to power set these, wait about 20 minutes and back at a 90 degree angle to a line between the anchors.We've only done that a few times, when we could hear the storms and knew we were anchored in silt. Each time we got to watch a few less diligent--or perhaps just unlucky--souls drift to leeward.

We can row an anchor out if the above procedure won't place the anchor in the right spot... actually, we've done this just once, to see if we could do it from the kayak (no problem). I've run big anchors out for other folks, helping them kedge off, using our tender. However, generally we can place the second anchor from the main boat, by using the engines to swing the boat against the primary anchor, though even that assistance is very seldom needed.  

Tip: the rode for the secondary anchor should be mostly or all rope with chafe protection. Because there won't be any yawing, chafe will be minimal. Second, it will be much easier to take out. Finally, it's not your sole anchor, and in the infinitesimally small chance the rode cuts (I've never heard of a V-twin rode cutting--there isn't enough motion), you still have the other anchor.

From "Rigging Modern Anchors." See the bookstore for the more up-to-date and complete explanation.

What if the boat is hanging to the second anchor in a strong wind in the morning? Attach an extension line and ease it off until you are hanging from just one anchor. Retrieve the main anchor while you are drifting back; this should be easy, since you may drift right over it. Then motor back up to the secondary and retrieve. If you don't want to let go, attach a long (150 feet) line to the secondary, release, and follow the same steps. Easy if you have a plan.

With practice, this typically adds about 5 minutes to the anchor drill and has never caused a bit of trouble.

New Canvas

Sewing gear back together is a traditional cruisers' pastime, and I've certainly passed time resewing the seams of our enclosure. I actually find it enjoyable, weaving the thread back and forth at anchor or dock, when there's nothing special to do. If there are sailors about a sailors palm is always a conversation starter.  Some haven't learned to use it efficiently, some are afraid to try their hand, and someone always has a good tip. However, after the Stayglass spit along the bottom edge this winter, it was time. Additionally, the glass had hazed and I've gotten tired of not being able to see well, rather like having cataracts or atrociously dirty glasses that can't be cleaned.

 

Courtesy of Canvas Connections, Deale, MD. They were timely on the estimate, stuck to the bid, and met my delivery requirement. It was over one boat buck, but it exceeded my DIY capabilities and that is worth payment.

I have also posted this to illustrate our genoa and spinnaker sheeting, since there have been questions. There is a sail track just forward of the aft cleat with 2 blocks mounted. The forward block is the genoa block, which is a good windward to beam reach setting (if broad reaching or running wing-and-wing for long, we move the lead forward like this). The aft block is for the chute (if the tack is moved to windward we can move the lead forward the same way, but seldom do). These lead adjustments are often made to be adjustable by pulling a line--and they were on my last boat, a high performance design (Stiletto 27 with many tweaks)--but I chose simplicity and fewer lines for this boat.

What else is obvious? Numerous rod holders, anti-chafe gear, stern mooring line redirection, window covers, and solar panels.

Note: the only products aproved for preseving and cleaning Staglass are by IMAR and are brutally expensive at West Marine. Defender is about $8/bottle less. They are good though, and Practical Sailor rated them the best performers. Just boat bucks....

Lessons in Electrical Trouble-Shooting

1. Never assume there is only one fault, even if the problem is new.
2. Never assume the previous owner didn't set you up. He did.
3. Always start with the multi-meter.
4. Always trace the wiring.

I travel altogether to much in my work, but there is a silver lining, beyond meeting good people and sometimes going interesting places; the boat is "sort of" on the way to the airport. Often I can manage a little time and get some hours and a night on the boat, though not always sailing time. Still, I'll take it. Projects that might subtract from sailing time get done and quiet time at the marina is bliss.

My last stay, as I turned in for the night I realized the reading light and fan didn't work in either cabin, and neither did one of the cockpit lights. Since my solar panel project had passed through both of those boxes and only those boxes, it seemed clear I had made some error that I could track down in the morning.

My multimeter battery was dead and I was too lazy to look for a replacement. I opened the cockpit light but found no obvious fault. Not surprising, since I had not disturbed any wires there. Then I dropped the ceiling on the starboard side. When I dropped the ceiling for the solar project the wires leading to the ceiling fixture had flown apart; the PO had done some stupid wring-size crimp connector splicing and everything came apart. I had right-size spliced it back together, but I had certainly guessed on some of the connections; there seemed to be an obvious pattern, I had used my meter, and I thought it was right... but I couldn't remember it I had tested the reading lights (I retrospect, I remember that I did). I tugged at all of the wires; tight and solid.

So I chased down a battery for the multi-meter. I had one on the boat, right where it was supposed to be and had the meter working in minutes. I should have done that first.

I checked the cockpit light. Power in, power on the pass-through. Clearly a bad switch. Since I picked up an unused spare at a marine consignment store for $3.00 a year earlier, a simple fix. It had been acting up and I should have figured as much, rather than place blame on the solar project. Easy. Two crimps and two screws.

 Lesson one: Start with a multi-meter. I checked the power on the starboard ceiling fixtures; no faults. Huh. It seemed the solar project was not involved. I traced the feed to the cabin lights. Sure enough they are separate from and unrelated to any other circuit (though there are many lights and fans on the "cabin light" breaker, the breaker feeds a pair of terminal strips and the aft cabin reading lights and fans run off a single feed from those strips. A mental light came on; we had a birthday party the week before with a group of teen age girls (my daughter is 16 now!) and as a result we had stuffed an unusual number of PFDs in the stern lockers... right where the cabin lights branch apart.

 

Proper wiring tools are essential

And sure enough, the PO had added fans and in the process, used crimp connectors. I'm a strong believer in crimps; I did hundreds for a 1-year hyper-saline salt chamber torture test for Practical Sailor Magazine, without a single failure. But the PO apparently either used a cheap tool or did not reset the tool for the fittings he used. In fact, the fittings were so far below standard size, that the die in my ratchet crimper for 2 gauges smaller fit perfectly; it should not have closed at all on that setting with that wire gauge. The wire had easily pulled out, without any damage, but remained hidden from view inside wire loom.

Problem solved for a few pennies... and at least 30 minutes of wasted diagnostic time because I was not systematic. Well, I knew better, now the lesson is further reinforced, my multimeter has a new battery, and now you know better as well.

 Lesson two: Never let your daughter count candles for your 50th birthday cake.

More Bike Weeny Stuff

I'm a fossil and come from the pre-cycle computer age. What's more, I like to understand machines so as to better work with them, but that desire doesn't extend to computers; I like to know as little of them as possible. Today's subject; bicycle gearing and attaching files to in Blogger.

For example, modern bikes have many gear options, the purpose of which are to decouple pedaling cadence from incline and wind resistance. In English, you can keep your feet moving at their best speed while the head winds and hills conspire to make you peddle too slowly.

Many have studied the whole business of cadence (peddle RPM) and how it relates to efficiency. Eventually all cyclists realize that when peddling easily a slower cadence is most efficient (70-80 RPM), when moving more briskly faster feet are more efficient (85-95 RPM), and when really delivering a best effort over a few miles, even more is is better (95-105 RPM). Why? Because slow twitch muscle fibers like low forces but are aerobically more efficient. Fast twitch fibers fire when forces rise. Curiously, the fast/slow naming convention is primarily a misnomer carried over from sport where higher speed and higher force go hand in hand. It's about high force/low force. It also explains why high reps just don't make you stronger.
 
While you can do this by feel, some calculations clarify, for me, what is going on:

Gearing, cadence, and speed calculations

If you click the down load tab to the right, you get a copy of an Excel file you can play with to your hearts content. Can't imagine why you would want to, but I needed practice.

Is this the best way? I seriously doubt it, but it only took a few minutes to figure out and it's a free service. Not bad.

Fossil Hunting in Fairhaven

rev. 5-30-2011

The Chesapeake Bay is famous for it's large, complete, and exposed Miocene Formation deposits, best know at the Calvert Cliffs, but extending from Fairhaven to St. Mary's. Since my daughter was small, we would walk these beaches, picking up shark teeth and molluscs and talking about what the Bay might have been like then. When she was very small, it was simple, fun talk of a time when the Bay was ocean, after dinosaurs but before people. Even a small child can see that shells belong to organism that are gone, and with a little explanation, to organisms that can't and don't live in brackish water.

Shark Toothed Dolphin  (Squalodontidae)

Some of our favorite places are the cliffs and beaches near Fairhaven. While the beaches are not littered with the large scallop shells that characterize Calvert Cliffs beaches, there are many small sharks teeth and other small shells, and occasionally something more interesting. Once, to our delight, a small section of vertebrae had been exposed by the passage of a tropical storm.

Thorasic Vertibrae

They were all broken up and scattered, and it took some time to assembly and identify the remains, not being a paleontologist and having only a rudimentary knowledge of mammal skeletons. A trip to the Smithsonian in Washington made it clear that it was a marine mammal, and trip to the Smithsonian Naturalists Center made it clear that it was a dolphin or small whale. Some reading about the formation and the discovery of a small whale skull by others, a short time later only a few feet away, makes it likely that this is from a small whale about 14 million years old.

Arrowheads are always tricky to date, even more so when found loose on the surface. Since there are no context or excavation clues, the best that can be done is compare this artifact to others that are better dated. This could be anywhere between one thousand and several thousand years old; I'm guessing Bakers Creek style, about 2,400 BCE since we have found others of that type in the area, but it's worn and could be older, perhaps 5,000-7,000 BCE.

Other times, it was evidence of our human past--and perhaps evidence that Fairhaven has been a nice spot for a long time. All I know is that my daughter could spot an arrowhead in a mall parking lot given time to look; she has found several on the beach.

Pretty neat.



Note: Since nearly all of the cliffs and beaches adjoin private property, stay on the beach and be a quiet visitor. Please do not dig anywhere as erosion is a serious problem. Additionally, that many of these cliffs are not too stable, and that after heavy rains collapses and land slides are common. There have been fatalities and some cliff beaches are closed for this reason (the cliffs grow progressively less stable, heading south). Do not climb on the cliffs.

Don and Steve Round the Horn.

 Cobb Island Lifesaving Station. Cobb Island, VA.  

Although this trip deserves and will receive better description, Don delivered the above documentary evidence of sailing around the Delmarva, nearly halfway by now. This photo doesn't really do the scenery justice, an old lifesaving station beat down by storms. Neither does it do justice to the feeling of elation at entering the harbor after passing one of the longer stretches of uninhabited and shelterless coast. The entrance itself is potentially tricky, moving with the passage of storms and not always marked correctly. The Coast Pilot suggest local knowledge, so it's a definite milestone. I imagine the sailboats that have visited this harbor--in the past few decades at least--could be counted on your fingers. Adventuresome stuff.

Steve and Don have sailed their Starwind 223 from mid-Bay, around Cape Charles, some 175 miles to get this far, and will probably cover close to 500 miles by the time they return. I expect some tall tales and fine photos.

The station about 80 years ago.

What a great way to start the season. They probably even got a jump on the flies!

A Minnow Trap from Recycled Flotsom

My back has flared up in annual protest for some perceived slight. I can't sail, I can't ride, I can barely walk. I can post something trivial.

Collecting critters and fishing may not be sailing, but I love them both. Even more, I love introducing my daughter to the natural world. Add to that father -daughter time the opportunity to teach a D-I-Y ethic, recycling and thrift all in one stroke; a bargain.

Any plastic bottle with a cap will do. Two are required. Any beat-up thing from the wrack line will do. 2-liter jugs are best, but even 12-ounce bottles do well.

• Cut the bottom off one.
• Cut the top off the other and insert it inverted. Leave the cap on the external neck only--it's handy for decanting the catch. The other neck, of course, is the entrance.
• Secure them together. I've seen everything from staples to cable ties to bolts to bits of string.
• Poke a few 1/8 holes near the neck to allow some water flow, carrying the scent of the bait our the inverted opening. Additional holes only attract fish away from the trap entrance.
• Tie a string around the neck to orient the neck into the flow, if any.
• Add bait. Bread is a good starting point.

We've caught minnows, spring peepers, small crabs, grass shrimp, and eels.

Something to entertain the kids and an idea to keep in your tool box for your next Cast-Away adventure.

 _____________________________________

 Post Script. We actually carry a commercial minnow trap, which gets heavy use, both at the dock and at anchor (use care at anchor not to wrap the line around the rudders--just enough line to get it to the bottom).

Aero Bars. Yeah, I'm off Sailing Topics...

Well, only for a while.

When I got back into riding I had carpal tunnel and the vibration was a killer. Aero bars were a life saver, worth sharing. I started with these:

When I got my new toy, I moved on to these:

The hinged model failed at the hinge from metal fatigue after only a few years of moderate use, which I reasoned was too little time.

Because I need a neutral wrist position I need a bar with an up-turned end. Would bar end shifters be better? No, I think I prefer brake lever shifters, since most shifting occurs on hilly terrain. The bars do add about a pound to the bike, but I don't live in the mountains, not any more.  

I think there is little question that aero bars are faster and more comfortable on the flats, racer or not. There is a learning curve: expect them to feel twitchy to start, but this soon passes; be careful on bumps; no, you can't reach the brakes, but you soon learn to switch one or two hands smoothly; set them high and wide when starting and stay far from traffic; if you're touring and value ease and comfort over speed, set them higher, further apart and not so far forward, and them leave them there. A little cork tape near the ends is nice too.

I'll repeat, they're not such a good idea in traffic. Moderation in all things.

A New Toy

Rev. 7-22-2024

[Many sets of tires, three chains, and she's still going strong! I've also gotten faster, the result of taking her out on the bike path every week, year round. Not like in my 20s, but it's a rare day that I get passed and never unless by some smart assed racer type, ... just like I was at that age.]

I dreamed of something like this in college, when racing was a passion. Then I destroyed my knee in a crash and spent 30 years waiting to ride again. What a difference aluminum and carbon fiber make.

Fuji ACR 2.0. If you can find old stock, a super buy.

 

 Now I am old, crippled, and unworthy. Perhaps I'll look fast enough if I simply lean it against a bench, pretending I've come far; Like Will Rogers, I've come far, so I should be satisfied to look the part. Perhaps I should paint it olive drab and scratch it up a bit.

I do promise that this will NOT be riding on Shoal Survivor's bike rack, dripping in salt. It's older sibling has inherited that chore.

PS. My wife tells me I have 2 mistresses now, both starting with "B": bike and boat. She's right. The past few nights have been consumed with tweaking and minor additions (water bottles, aero bars to support my sore wrists), just like the boat.

Solar Panels

Rev. April 20, 2014

Cruising farther means more nights on the road. Limited battery capacity flat means more nights in marinas. That's money, but more importantly, it means bending our plans to fit in marina stays, and I don't like that. We could go sans power, but when the mid-summer Chesapeake humidity hits and the wind fades, fans equal sleep.
 
The Choices
We could run a Honda generator or use a wind generator. Too much noise. I like passive and silent, so panels it is. We have a substantial deck, but we use all of it, either lounging or sailing. Only 2 small areas on our hard top remain low-traffic, no more than 15 square feet.

We have 270 amp-hours (AH) in nameplate storage  capacity from 3 x group 27 batteries, but realistically we can only use 140 AH without straining the batteries and shortening their life. We know from experience that we run about a 40-70 AH deficit each day, depending on use of lights, DVD, fans, and CPAP.

The available 15 feet square will fit 2 x 100-watt panels, or about 60 AH in real-world charging capability, if we consider shading and passing clouds. While this won't replace out entire deficit when we're energy hungry, it will stretch our battery life and may be enough if power is used responsibly and charging is supplemented with some coincidental engine time. For better or worse, this is our chosen compromise.

The Panels
Price matters. We also needed a specific shape. I hunted for something cheaper with good customer ratings and came up with these:
Renology 100W

They are of a simple design that appears to be well executed. I load tested them in the front yard, in the sun, and they were on the numbers. Nice wiring boxes; however, accessing an additional knockout required some very careful drilling (we padded and protected the back side of the cells with thin plywood over cloth), since smacking it firmly with a screw driver seemed unwise. Once inside, there are plenty of extra terminals.

(Note: to "yard test" the panels you will need a load close to the projected out put of the cells. Other wise, you will be so far from the maximum power point you will see a much lower value.Of course, without an MPPT controller in the circuit, this means running a bulb at 18 volts, so keep it brief!)

The Mounting
The adjustable feet used to compensate for the crown in the hard top may be handy any place a self-leveling or adjustable mounting is needed, just as threaded studs are used to mount and level engines, traffic signs, industrial equipment, and outdoor lighting poles; perhaps the only innovative part of this installation. they neatly address the recurring challenge every D-I-Y sailor faces who lives and hour from his boat but likes to tackle significant projects; how do I prefabricate as much as practical and insure it will fit easily and properly when I reach the dock? This was a true piece of cake.

The hard top is not flat; in fact, it domes asymmetrically about 3/4-inch over 3 feet. Additionally, we need to protect the panels from accidentally dropping of the boom and provide air flow under the panels (PV cells lose efficiency when hot--more on that later). I also dislike the idea of drilling holes in a foam core deck. The solution? A simple aluminum frame and 4 adjustable feet for leveling and load distribution.

The feet are 1 1/2" x 1 1/2" x 1/2" prelaminated FRP with 1/4" x 1 1/2" stainless threaded rods tapped and epoxied in place. This material holds threads very well, and even without the epoxy, any thickness over 3/8" will break the bolt or strip the nut before stripping the FRP threads (I tested a few trial pieces to destruction).

Note: remember to degrease bolts and rods before embedding in epoxy. Residual thread cutting lubricant will interfere with the bond. A little sanding is good too. In this case, however, because the nuts tighten against each other, there is little torque on the rod.

Installed with nuts and washers above and below the aluminum frame, these provide a solid mount that easily accommodates the curve of the deck. In my case I embedded the cut end of the rod in the FRP block, but in some cases it may be desirable to leave the studs very long and then trim after test-fitting. To insure that the threads are not spoiled when the rod is cut, be certain to thread the nuts on first. After cutting the rod, camfer the cut end and then remove the nut to straighten the threads.

These are another excellent choice, though less "trick" looking. I have used these for interior equipment mounting, including bolting down an air conditioning unit. From Duckworks.

The frame is nothing more than two  2" x 2" x 1/8" aluminum rails bolted to pre-drilled holes in the underside of the panel frame. These rails are as stiff as a pine 2 x 6 and are high enough to keep the boom off the glass. The slightly elevated mount allows free air circulation under the panels for cooling and drying. To insure good alignment...

Note 4-20-2014: The boom has contacted this frame numerous times, occasionally with considerable force (me winching, not realizing the boom is resting on the frame) with no damage. I think the design is about right and would not go any lighter in this location.

• Drill the holes in the frame only slightly oversize (+ 1/32-inch) to insure good bolt alignment. Wobble the drill slightly to create an allowance for misalignment.
• Dry-run the installation, adjusting the legs to the correct height.
• Tape off the outline of each foot to minimize the epoxy mess. Sand the gelcoat surface.
• Bond with thickened epoxy (West System with fumed silica/Cabosil). Tighten the nuts slightly to insure the feet are aligned vertically with the frame. Remove tape before the epoxy cures.
• Be warned, the whole assembly will try to slowly slide off the deck. Temporary props and duct tape may be useful.
• Remove the masking tape before the epoxy is set. It become very difficult later.
• After final cure. remove the equipment and frame and re-drill the mounting holes about 1/32-inch larger to insure easy removal in the future. If there is significant crown on the deck, there may be some binding during this removal step because the studs will not be parallel to each other.
• Reinstall and tighten the nuts.

Although this sounds convoluted, it is simple and fast and insures that the panels can be removed in minutes for for final wiring or any future trouble shooting. All parts are easily prefabricated at home, always a plus in convenience, time, and workmanship.

Pre-bonding adjustments were made.

The Charger
A 15 amp charger with an LCD screen is mounted in the starboard hull equipment bay, behind the steering gear and galvanic isolator. Short wire runs, out of the weather, and easily accessible. PDQ did a nice job with the access panels.
Morning Star 15 Amp charger

What about MPPT (Maximum Power Point Tracking) chargers? Photovoltaic cells (PV) don't simply crank out 12 volts of electricity and magically charge batteries; they put out something between 23V and 0V at variable current. The maximum power point, where V x I = W is at a maximum, is generally at about 16.4V. An MPPT controller senses this and keeps the panel output in the sweet spot while providing the battery the voltage it requires for proper charging. That is assuming cool temperatures and a blue sky.

For a little more on MPPT charging, Wikipedia is always a quick source: Wiki on MPPT chargers

If there are clouds or haze, or if the panel is heated above it's rated temperature, the maximum power point will shift left, to lower voltage. On the Chesapeake in mid-summer heat can easily shift the MPP from 16.5V to 15V. What is the actual required charging voltage? That varies with the state of charge; when near full charge 14.5V is a very good match, but when first charging a 50% discharged battery we may need only 12.2V and some efficiency will be lost, perhaps 16%. MPPT is at it's best when first charging deeply discharged batteries.

What does a power curve look like? The below table and graph are for a 1.1 watt panel, but you can easily scale it to fit your application. All 36 cell panels will have very similar voltages and power curves, regardless of wattage. This graph assumes 75F ambient temperature, a high sun and a right angle orientation, and NO shading or cloud cover.

How much does heat lower efficiency? the output voltage is lowered by about 0.041V/F, or about 1V lower on a scorching day than on the cool spring day when you did your installation (assuming you allowed good ventilation to the underside--it could be worse). In other words when it hits 95F, the MPP voltage will be about 16.4 - 1V = 15.4V. Since out electric load is maximum on a hazy 95F day, this is the most relevant MPP. (Some will argue that cool weather charging is more critical, since the days are shorter, nights longer--more lights--and the sun lower, but it is running the fans in the summer heat that always does us in. Plan according to your reality.)

Shading due to haze lowers the output amperage but does not significantly lower the MPP until severe (evening or heavy clouds). Spot shading (a sail or even a shroud) can be devastating, depending on whether it takes a portion of a column (small amperage drop) or a row (small voltage drop that effectively shuts the panel down). However, the reason we did not put a panel under the boom was not shading (if we want zero shading we take the boom far to the side); it was because we walk there when furling the sail and wanted to leave one free impact zone where we wouldn't worry over sailcovers and ropes and even loungers.

For some detail on panel output corrections: PV cell output

Series vs. Parallel Wiring
This has been debated to death on the web. When panels are wired in series an MPPT controller can deliver slightly more power during periods of low light; simply put, the voltage can stay at usable levels longer and resistance losses can be a bit less. However, if any shading occurs, the drop in output is much larger than it is in parallel installations, where only the blocked cell is depowered, not the train. For boats where some shading is likely, parallel wiring is more practical. For a terrestrial roof top installation, series wiring and higher voltages can be explored.

And I didn't even analyze the shading loss owed to seagull poop. It turns out we can't really see much difference when we clean the panels; I guess we're disgusted long before it is functionally too bad.

I've probably given up 5-10% in charging capacity on a typical day by using a simple controller. I suspect for most people, larger panels are a better investment at this scale, but it could go either way; for a project over 200 watts, choose an MPPT controller.

Wire Routing
I expected hiding the wires to be a battle, but pulling the wire took less than 30 minutes. Unique to the PDQ 32, but here it is:

• The panels are connected to each other above the deck by hiding the wire (2 x 12 awg) in wire duct. The stuff is intended for hiding phone cables, is strongly self adhesive, and would probably fit 3 x 12 awg or 2 x 10 awg wires. It snaps open to the side, should you need to service the cable.
• From the panel to the deck above the helm light is only ~ 2 1/2 inches; wire loom covers this.
• From the light to an existing hole in the stainless hardtop support is only 2 inches. Again, a bit of wire loom covers this plus the existing wires nicely.
• The wire runs down inside the support, forward across the aft cabin ceiling above the liner to the steering gear/instrument cluster access, and down to the charger, below the galvanic isolator.
• From the charger to the main bus bars.
• In-line 15 amp fuse between the bus and charger.

Total wire run, about 15 feet each side, 10 AWG.

Total Cost
With all materials (of course, the might-need stash coughed-up some bits an pieces, including the wire and FRP), about $700.00. I struggled with the decision, but if it becomes a 20-year investment and saves a few nights a year charging batteries for $1.50/foot + electric + taxes, then I come out ahead in only 2 1/2 years. Not too bad and better than my 401-K in the best of times. Installation only took 8 hours, including making the feet and frame at home, so not too bad. Time spent puzzling it through? We don't count that.

Afterwards:

• The birds love to poop on the boat, but unless the situation is awful, the amperage drop is only a few percent.
• I've seen panels installed under impressive crash bar protection, but this amounts to permanent shade.
• I've unplugged from shore power as there doesn't seem much use in running both (if I had a large sump pump I might reconsider this, but I have none). Moreover, both systems have charging algorithms the float and equalize, and they can easily confuse each other. One less thing to disconnect when day sailing, an advantage I had not foreseen. 
• The panels easily manage any day sailing usage (1-8 amps) before we even return to the dock.
• While sailing one panel is often shaded, while the other is almost always clear. When anchored, both are easily exposed by swinging the boom off and securing forward.
• Summer charging has been great, but cloudy fall weather has been troublesome: shorter days, more clouds, and longer nights.
• Typical output, with no shading: 9 amps at 14 volts on a sunny day, 0.8-2.5 amps in heavy clouds. The most I have seen was 9.6 amps, and by Fall 7.4 amps is good, given the lower sun angle. The reality is that without angling the panels toward the sun you will always see somewhat less than the rated capacity. While sailing everything depends on the course; both panels may be shaded, or neither.

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Follow-up, March 25, 2012: Amperage on sunny day still tops out at 8 amps, about the same as day-one when corrected for sun angle.

April 20, 2014: Still charging at the original rate. No sign of water intrusion.

August 11, 2016: Still charging at capacity.

 After 5 years.