Friday, April 12, 2013

A restless night

We did not get under way this morning.  For one, the weather is not cooperating -- it's blowing 15-20 right now, certainly enough to make it a challenge to keep the boat in a narrow channel.  Moreover, we slept right through what would have been the optimal departure time, owing to the fact that we had a partly sleepless night, due to that same weather.

An integral part of the learning curve with any new boat is developing confidence in your ground tackle.  For us, there is the additional issue of confidence in our anchoring technique.  Last night was our first real test -- up to now, conditions have been mild, to say the least.

One of the negatives mentioned about this spot in several reviews was that there is no protection here from the wind.  And as I wrote earlier, the tidal current here gets up to around four knots.  Last night the leading edge of a line of storms arrived here, and winds quickly built to 15-20 knots with gusts to 30.  For a good part of the night, the winds and current were from opposite directions, making for some interesting boat motion.  Several times I checked on the anchor rode and it was running down from the bow and behind and under the boat, with the snubber/bridle tight against the boat sides.  Every time the boat ran into the chain like this there was a mighty clank; steel boats transmit this kind of sound absolutely everywhere.  Given that the anchor roller hangs only three feet or so beyond where the bow meets the waterline, I'm not sure there is much we can ever do about this, short of adding a longer pulpit.

We've been lying on a little more than 5:1 scope since we arrived.  "Scope" is the ratio of the length of anchor rode to the distance from the bow roller to the seabed at the anchor location.  We calculate that by taking the depth sounder reading where we drop the hook, adding any additional tidal depth from the tide chart, then adding six feet for the distance from the water to the roller.  We selected this spot because the charted depth is 16' MLW, whereas there is a 40' hole just north of us and a 20' hole just south of us.  We confirmed the charts by driving around and reading the depth sounder.

Allowing for tide and pulpit height, we needed to account for about 26' of depth where we dropped anchor, and a 5:1 ratio calls for 130' of rode (including snubber).  That's what we paid out when we arrived.  Now, before I go much further, I should say here that the amount of scope required is dependent on conditions as well as the ground tackle itself, and there is something of a religious debate about it anywhere you look.  One of the more hotly contested topics is whether an all chain rode or a mostly rope rode is better; in our case, the boat came with 400' of all-chain rode, so that's what we use.

While 7/16" regular carbon chain would probably be more than sufficient for a boat of our size, displacement, and windage, we instead have 1/2" high-tensile chain.  In addition to much greater strength, the larger chain is heavier, at over two and a half pounds per foot.  This plays heavily into the scope equation, as the heavier chain will tend to lie flat against the bottom for a much longer distance from the anchor.  The goal is to have the force on the anchor be as nearly horizontal as possible -- any vertical component pulling up on the shank will try to dislodge the anchor from the bottom.

Lots of people will tell you that 7:1 is either the ideal scope or the minimum scope.  Where that number comes from is simple trigonometry coupled with the anchor manufacturers' specifications on the maximum permissible angle between the shank and the bottom for proper holding.  The math works out that the maximum permissible angle will not be exceeded at a 7:1 scope, even if the connection between the shank and the boat is a straight line.  This assumes all the "sag," known as "catenary" (appropriately from the Latin for "chain"), has been pulled taught, a condition many refer to as "bar-tight."    The amount of force required to bring 130', over 330 pounds, of chain bar-tight is considerable and can be calculated.

While I would love to have 7:1 out, which would provide a much greater margin of safety, there are always other realities to contend with.  Here in Price Creek, there is only about 360' total between the six-foot MLW depth countours on either side.  That means that the "shadow" of our rode on the bottom, assuming we precisely set the anchor dead-center, should be at most 180' long.  Otherwise our swing circle could encompass water not deep enough for us.  In light winds, generally the boat will just travel back and forth in a narrow pattern over the anchor as the tidal current reverses.  In high winds, however, all bets are off, and at low slack, even a modest wind can push us to the shoreward edge of that circle and aground.

Since nailing the anchor dead-center is a virtually impossibility, and the anchor may well un-set and re-set itself with every tide change as the rode pulls against the shank in the opposite direction, we need to leave a buffer of at least a boat length on each side, arriving at that 130' number.  Fortunately, 5:1 on our heavy all-chain rode is sufficient in most conditions.

Last night, as the winds increased and the boat started moving more and more erratically, we opted to put out another 25' of scope, bringing us closer to 6:1.  We felt we had a good set near mid-creek, so decreasing our swing buffer was an acceptable tradeoff.  Nevertheless we were quite nervous, and whenever either one of us got up for any reason we went upstairs to check on things.  We also had an anchor alarm set on the iPad with the Drag Queen app, from ActiveCaptain, with a short leash.  It woke us up once, as the current reversed and we bounced to the end of the rode.

Today conditions are even worse, with wind more or less directly across the channel, and we found ourselves inching closer and closer to the lee shore.  Rather than take any chances, we moved the boat, re-dropping the anchor a little closer to the windward shore.  The high winds should let up sometime this evening and we will once again drop closer to center and tighten up the scope a bit.  We'd like to get an early start tomorrow, so I hope we will get some better sleep tonight.  I'm typing this in the pilothouse, so I can keep an eye on the instruments as well.

I did take advantage of yesterday's downtime to get another few things done.  One project was to trace out the wiring to the currently unused aft-deck freezer, which has been nevertheless drawing current to run it's temperature display and heat the lip seal, with no way to turn those off, apparently.  Turning off the breaker also killed the power to the AC receptacles in the pilothouse, where, among other things, the aforementioned iPad is plugged in.  I was finally able to isolate the circuit onto a breaker by itself, so now we can keep that phantom load off.  We're trying to sell the freezer anyway; it's a really nice one, but we'd rather have the space on the aft deck for relaxing and entertaining.

I also spent some time reconciling differences among the four (!) separate voltmeters connected to the house batteries, none of which agreed with my handheld meter.  I was able to recalibrate one of them, but the all-important state-of-charge meter is reading about a volt low, and I need to delve into that one further.  We also spent some time figuring out exactly what else can be shut down to conserve power.  I came up with a plan to keep the essentials, including the iPad, running without the inverter, so we can drop its substantial idle current from the mix, at least overnight, but we opted not to implement it last night, as the iPad anchor alarm is a critical system, and I did not want to impose yet one more systems change on top of an already stressful event stream.

In regards to the failing battery plant, which is necessitating all this detailed power management, long-time reader and fellow bus enthusiast Tom asked why we did not simply transfer the 8D AGM batteries from Odyssey, which I replaced only a couple of years ago, to the boat.  That's a good question which brings up the broader picture of Odyssey's future; one could argue that not only batteries but many other items such as the microwave, TV, inverter, transfer switch, water pump(s), and diesel boiler could just as easily be cannibalized from Odyssey and used on the boat, saving us a few bucks.

As to the batteries specifically, I did consider it, but more from the standpoint of expedience than cost savings.  Ultimately, there were two major reasons that I dismissed this idea very quickly.  The shorter but less important reason had to do with the return on my labor.  Long-time readers will remember that changing the batteries in Odyssey was a major undertaking -- nothing will make you feel like an old man faster than having to manhandle eight 175-lb batteries in a tight crawlspace.  It ended up costing me a bottle of bourbon and a dinner out for the warehouse manager who so generously helped me, in addition to the toll it took on my own body.

Getting batteries in and out of the boat will be no picnic, either, but the working room is a bit less restrictive.  Still, to "trade" batteries between the two would be a very labor-intensive process, and then we'd have batteries on the boat that are nearly two years old, or about halfway through their service life.  Meanwhile, Odyssey would be left with virtually no battery capacity at all.  For the amount of labor involved, I'd rather leave the bus with a half-used bank, and spring the money for a completely fresh set here on Vector.  Of course, that makes no sense until we correct the charging issues that damaged the batteries in the first place, a condition which also would have made short work of whatever was left of the Trojans from Odyssey.

The more important reason speaks to all those other items we could, conceivably, have moved to the boat from the bus.  Chief among those is the inverter, a model no longer available and whose capabilities I will have trouble duplicating here.  Here, the short answer is that this would be tantamount to "parting out" Odyssey.  While that is certainly a viable option, and we considered it (very briefly) when thinking about our options once we moved to the boat, it would really be an admission that the bus held so little value, either to a potential buyer, or even to ourselves for some future use, that it made more sense to scrap it after salvaging what we could.  Devoid of any of the house systems that make it what it is, a 28-year-old empty Neoplan shell has virtually no market value at all.

In fact what we decided is that Odyssey is, indeed, worth a fair amount.  Perhaps we will not succeed in convincing anyone else of that well enough to persuade them to buy it, but it still holds value to us.  So much so that we have budgeted funds to store it and maintain it indefinitely, until such time as we need it again, someone comes along to buy it, or we deem its value to have dropped to a point where the storage no longer makes sense.

Thus, Odyssey will remain fully functional, batteries and all, for the foreseeable future. This will come in handy almost immediately, as we are planning to move back into the bus at the boatyard while Vector is being worked on.  This will allow the workers to remove as much of the stateroom finish and furnishing as necessary to access the bilges, where the real work needs to happen.  Once we are done at the boatyard, we will start to market Odyssey much more aggressively.  As much as we would miss her, I'd much rather see the bus being used regularly by someone who appreciates it than sitting forlornly in a storage yard waiting patiently for her masters to return.  The money would be nice to have in the cruising kitty, too.

Tomorrow the weather will be better and we plan to weigh anchor and get underway at 08:00, which will give us two feet and rising at the mouth of Price Creek, and put us past all the skinny water near McClellanville just before high tide there around 11.  As I am typing these last few lines, another trawler, Slow Churn, has appeared in our heretofore un-shared anchorage, giving us even more reason to be mindful of our scope.  Once the wind and current align this evening, we will re-set the hook closer to channel center, and with winds back down in the 10-15 range, tighten back up to 5:1.


  1. Just out of curiosity, what is your depth sounder calibrated to ?

    I have mine set so zero is the bottom of my props which equals 4'8" on my boat.

    Bill Kelleher

    1. It was set to depth of water (below surface) when we bought the boat, and it turns out I prefer it that way. Lots of folks prefer depth-under-keel, but with a draft of almost exactly one fathom, I know instantly how much is under the keel by seeing depth below surface, math I have to do anyway with the soundings on the charts.

  2. Maybe in some more serious situations you and the "crew" might have to sleep in shifts to keep tabs on weather conditions?

    1. We did consider it, and I am certain the time will come when we need to "man the anchor watch" over night. We are certainly prepared for standing watches overnight anyway, as it is necessary on longer passages. Even making the Bahamas in this boat, except on a very specific itinerary, requires an overnight. We are willing to do one night on our own (or two, in an emergency), but beyond that we will have at least a third crew member aboard to help stand watch.

  3. Sean --

    Sorry about the rough night. I have experienced anchoring in the conflicting winds and currents in the area and there is no easy solution. Once, when we were threatened with a hurricane (which thankfully stayed far offshore), I got seriously worried about how the anchored boat would deal with a blow if the current was holding me so that the boat would not face into the wind. I ended up using a large stern anchor and facing the boat into the anticipated wind. The result was that the boat was sideways to the current, no matter which way it was moving. I got some interesting movements, but I preferred to have my nose into a possible hurricane wind. I've done the same thing in a previous boat in an actual hurricane near Mobile, Alabama, but we were tied off at the stern to trees rather than using a stern anchor, and it worked out well.

    I realized reading this that I offered you my large hurricane anchor and never got it to you. It is too large to easily stow on the boat unless you had some kind of mounting made for it on deck. It is too large to go into the aft deck opening to the bilge. You are still welcome to it, as it will not help me much in the airplane. Perhaps I'll send you a picture and some measurements when I get back to Savannah. I'll be over there tonight and get to this next week if you are interested. I also have some serious hurricane rope that you are welcome to as well.

    1. Thanks, John. I had forgotten about that, too. Please do shoot me the dimensions and photos. If I can find a way to stow it, I would love to have it, and while we are at Deltaville next month would be a great time to have a mount fabricated. If I can make it work, then I will come get it from you when I come back down to retrieve the bus. I'm also happy to have whatever other lines, fenders, or other miscellany you have lying about from your flight-level-zero days.

  4. I've enjoyed your postings on the T&T forum and now this blog. As you get to be an old hand at cruising those waters, you'll learn a few things. One, unless there is a river upstream, you will have significantly less current issues anchoring above or west of the ICW, rather than between the ICW and the ocean. We always used Dewee's Creek / Long Creek in that area, both because they fit that spec, and are much wider than Price's and others. There are a few clumps of trees here and there to get in the lee of under certain conditions, though I don't think they did much good. Holding is excellent too. I am not sure what your anchor is, but it sounds like you have very heavy ground tackle, which is good (until the windlass breaks, that is). 3/8" BBB chain and a 88lb Delta have held our 60 LOA 80,000lb boat through all kinds of nasty, shifting stuff. More scope is always good, but over time you will find you can use 3-1 most of the time with that kind of gear especially as the water gets deeper; but that will come with time and experience as it relates to you and your boat.

    As you get closer to Morehead City / Beaufort, let's see if we can meet. We are usually either at Morehead City Yacht Basin or anchored at Cape Lookout at given time.

    56 Hatteras MY

  5. Hi, I can only imagine your concern when anchored with current / tide in one direction and wind in the opposite direction. Such a condition even affects me and I am on a 16 foot pontoon boat fishing off Marco Island in the backwaters. I have a 40 ft Monaco RV in Naples. You are living my dream on your boat. I would like to do the circle from here to the Mississippi and up to Detroit, and then return to Naples via the St, Lawrence seaway. But at 75 years, not much chance.
    Enjoy your boat. I really enjoy your blog. ernie

  6. Your cats were sea sick at first, how are the cats taking all this boat movement now?


    1. Hi, Mike. Thanks for checking in on the kitties. Other than Angel's one big barf fest when we were out in the open ocean, they've been perfectly fine. George usually sits on the pilot house settee while we're under way, and Angel goes back and forth between the helm chair and the saloon.

      We'll see if Angel has trouble next time we see anything rough.

  7. A Victron inverter should do all that your old one on the bus did, and more.

    And... Lithium's might at last be worth considering too. I've seen some great prices on 1000Ah cells. :-)


    - Chris

    1. I'm pretty sure it was I who first alerted you to Victron (in August, 2011 -- not that I am keeping track, but Gmail never forgets...). You are correct in that Victron units do have many of the same capabilities, but, as I wrote way back then, I have concerns about their US service and support. That's a bigger concern here on the boat than on the bus. They're also very spendy, as you know. The big reason why they are not tops on my list right now is that I can't actually use the "load support" capability here on the boat -- we have a 16k generator, and our shore power comes in through an isolation transformer, so it's 50 amps or nothing at all. They are still in the running, but I am looking more towards a pair of inexpensive far-east units that do not have integral chargers, with a separate high-current charger (or two). Nothing firm yet, and all will be disclosed here on the blog when I know more.

      As to lithiums, they are still not yet at a competitive lifetime cost, per kWh "banked," as compared to AGMs. The significant weight and space savings, a real advantage in the bus, do little for us here on the boat. But I did review the state of the technology while noodling through the battery/inverter problems, just to be sure. I'll be looking at it one more time when it comes time to actually buy all this stuff; the key challenge right now is finding a replacement alternator to fit the existing mounts and belts that can be externally regulated and is 24-volt.

    2. I could have sworn it was Ben who first showed me a Victron data-sheet, long before August 2011 even. But you might have been the one who started him on that track...

      FYI - when I bought ours, I found that by calling and emailing around to dealers I was able to track down an inverter/charger for substantially less than list and way below the lowest advertised prices - it ended up not costing much more than a new Xantrex. I never did find much discounting of MasterVolt though.

      Though without being able to take advantage of the load support features, I totally understand why you'd go with something different.

      And as for lithium pricing... Balqon is currently selling 1000Ah cells for $740/ea. $6000 for a 24V 1000Ah battery is pretty close to what you would pay for Lifeline AGM's, before you factor in any other Lithium advantages. Let me know if you want any links - I've been sending Ben stuff to help him finish speccing his bus.

      And besides, the bleeding edge is fun.... ;-)

      - Chris


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