Thursday, 24 July 2025

2025-2026 Cruising aboard Sakura

This is very much a "living document" which will be updated as plans begin to take shape.

Das Boot

Non-sailing friends often ask basic questions about Sakura and I do a pretty poor job of providing a non-geeky description, so I’ll try here.   
Sakura is an Alubat OVNI 435, a 12.9m (43’) Aluminum sailboat, built in France specifically for rugged, reliable ocean sailing in very demanding conditions.   This type is sometimes known as an expedition yacht and is very different from a fibreglass production boat intended for coastal sailing or chartering, (even though both look like ‘sailboats’).   OVNIs are sometimes  called the 4x4 of yachts, meaning they can go anywhere.   (and, hopefully return!).  One of the unique features of the OVNI series and similar types, is that keel and rudder both retract, allowing access to very shallow waters.  
This size of boat is the largest I feel I can manage single handed (whether solo or not) while being  big enough to be comfortable and fast (ish) sailing offshore, and  as a compact but well-outfitted home for two and occasional guests.   This size permits 3 double cabins for crew and large tanks to carry sufficient fuel, water and provisions for extended travel, and she is generally designed for sailing offshore vs vacationing in marinas or accommodating 6 charter guests for a week.  .   

Travel Considerations

The Government of Canada website provides a summary of travel advice and advisories by country here..    Be aware of vaccine requirements, which on the Caribbean islands are fairly routine, though Yellow Fever is present on the continent.  Be aware that if you lack proof of a Yellow Fever vaccination, and have travelled to a country where it is present, you may not be permitted to subsequently enter a country where it is not present.   A summary of the current requirement is here.      

Sakura is currently (September 2025) on the hard in Curacao, and will be ready to sail at the close of the 2025 hurricane season, (June 1 to November 30.)    

Planning a sailing  route involves exploiting the prevailing winds, which, at Caribbean latitudes generally blow north easterly to easterly at15-25kts.  (see below)  These are known as the ‘trade winds’ because they are strong and constant, and defined trade routes in the days of sail.  

Simplified North Atlantic trade winds

The intention is for Sakura to join the legions who cruise and charter in the lesser Antilles ( the smaller islands, running north-south from British Virgin Islands to Trinidad) between December and May, with visits from friends and family.   These islands are popular winter tourist destinations for obvious reasons, but this area is a winter sailing playground specifically because the winds now fuel the tourist trade - sailors who enjoy straightforward sailing between islands that are usually within sight,  and are a day's sail of each other.         


At the moment though (Sept 2025), Sakura is nearly 500 NM south and west of the Lesser Antilles.  This means that initially, Sakura must be delivered from Curacao, upwind, somewhat against the trade winds,  to make landfall somewhere near the north end of the island chain.   

The draft timeline as of Sept 2025 is as follows:

November  2025  

Fly to Curacao Oct 27 to complete refit of Sakura through November, ideally launch, (update survey and insurance) and first sea trial mid November.

Early December 2025 

Mike and Mark fly to Curacao Nov 29.

Curacao>Klein Curacao>PR>BVI

The Curacao to BVI trip comprises three stages - first is a 20NM shakedown to Klein Curacao, and from there north for 400NM, to Puerto Rico., then a day to windward to the BVI.   

Klein Curacao is a half-day hop from Curacao.  This provides an opportunity to test the boat and and confirm that all systems are working properly, and will provide the opportunity for any revisions or fine tuning that might be required, and an easy run back to Willemstad should any major issues become evident.   Depending on weather and circumstances, we could spend two nights at anchor, with a day's circumnavigation of the island as a test sail, however much depends on the weather forecast.   


Passage NE from KC to PR (400 NM)

Depending on conditions, KC to PR this would be a 3.5-5 day passage.   


East from PR to BVI   (80 NM)


From my father:

Looking at your projected trip, the passage to PR in particular, it occurred to me that if you need to ease off on the windward beat it would not be a big deal to make your landfall further west on the PR coast. As I recall the winds along the coast were light and gaining easting would probably be easy along the coast toward Vieques and/or Culebra. From there it's a short hop to USVI. (If I were to enter the USVI territory I would just anchor off for the night or simply continue to the BVI. When we headed to PR from the BVI we found a place to anchor for the night a little way west of Charlotte Amalie and never had to clear into US customs.) Of course we did it in the opposite direction and it may have just been lucky that the winds were light. Our final destination was Boqueron on the SW corner. From there we headed back home. Along the south coast of PR we were in the lee of the trades which were usually NEasterly. Clearing in to USVI customs was never a pleasant experience, even those many years ago,


From Ronnie R, a Puerto Rican sailor who has done the route north from Curacao>PR  many times.  

Heading N, a weather window for me is a minimum 3@4 days of decent E (or SE, S) wind speed between 10 and 16 kts, maybe 17.
The 45nm trip from Curacao to Bonaire is a nice one day sail (no power) avoiding sailing close to the SE tip of Curacao as your friend recommended.
Besides the current, the waves are usually big and from all directions.
On my way to Bonaire, I usually stop overnight at Klein C, something I recommend if you haven’t been in that beautiful island.

[Ronnie then shares that while Bonaire is is a Bucket list destination for divers, it an expensive and limiting sailing destination, where anchoring is prohibited.   Little is gained by sailing there if the intention is to sail North, and that any easting gained is of little consequence.  ]

You will be able to sail straight to the BVIs only with SE winds, very improbable in November, but possible since it happened to me two yeas ago in my fastest ever crossing, a 42 hr incredible pleasant dream.  [Ronnie has a catamaran, so his average sailing speeds are higher]
But, that is not a big issue because once in PR, it is quite easy to get to the BVIs.
I will send you an article I helped the author, Don Street, to publish in some nautical newspapers.
Usually, the trips takes me around 50 hours.
I remember 4 or 5 that were 46hrs and the longest, 66 with light NE winds that took me to the Mona passage.
From there I motor sailed 11 hours to Salinas.

The article referred to above is excerpted below, and explains the south coast of PR in some detail.


Sailing Eastward Along Puerto Rico’s South Coast

Puerto Real to Vieques

by Don Street
Are you among the sailors who plan to come from the east coast of North America to
the Caribbean in the fall via the “Thornless Path” rather than sailing offshore directly to
the Lesser Antilles? Here is some advice to make the trip easier and more enjoyable.
This article is based on numerous exploratory trips along Puerto Rico’s south coast, on
Iolaire and Li’l Iolaire from the early ’80s to 2002. Experienced Puerto Rican yachtsman
Ronnie Ramos checked the article for accuracy, updated information where necessary,
and added numerous important bits of information.
Just a few days before I started writing this article I skimmed through my 1966
Cruising Guide to the Lesser Antilles; the piloting and sailing directions are just as true
today as they were in 1966. The 2001 edition is available from Amazon.com.
Having fought your way eastward through the Bahamas or along the north coast of
Hispaniola, you’ll arrive at the western end of Puerto Rico. Clear in at Marina
Pescaderia (https://marinapescaderia.com), relax, and then spend a few days enjoying
their facilities and exploring the village of Puerto Real to get a flavor of the wonderful
Puerto Rican hospitality.
You might be dreading the next leg: to Vieques in the “Spanish Virgins,” the ideal
jumping-off spot for the short sail onward to the US Virgin islands. It can be a 110-mile
slog to windward against the westward-flowing equatorial current along the south coast
of Puerto Rico. However, if you take advantage of the land and sea breezes, you can
sail from one anchorage to another with no long hard beats.
Start early for favorable winds
The south coast of Puerto Rico has built-in air conditioning — the katabatic winds.
The hills are so high that as soon as the sun sets the air cools and falls down off the
mountains, counteracting the tradewinds and producing a light northerly breeze that
continues at dawn. Then, after the sun warms the hills in the morning, the breeze will
switch to northeasterly then easterly and sometimes southeasterly. If it goessoutheasterly it allows a long starboard tack along the shore, with occasional short port
tacks when getting too close to shore.
The key to sailing eastward on Puerto Rico’s south coast is getting an early start. In
1993, the engineless 46-foot yawl Iolaire left Boquerón, just south of Puerto Real, at
about the same time as a group of four yachts cruising in company that was also
heading east. Almost every morning Iolaire was underway at the crack of dawn, taking
advantage of the light northerly, which would slowly switch to northeasterly than
easterly, increasing as the day went on. By 11:00AM we had a nice fresh easterly or
southeasterly. By noon, when the wind was on the nose and really increasing, we were
sailing into an anchorage. About 4:00 or 5:00PM our friends would come staggering in
with tales of battling 20- to 25-knot easterlies.
Lobster pots and fish traps
While heading eastward in the early morning, careful navigation is necessary as the
sun is low and ahead, making eyeball navigation difficult but possible. Your chart plotter
and GPS are useful instruments but eyeball navigation is more important, glancing at
the chart plotter and GPS now and then. Lobster pots and fish traps, often marked by
nothing but a Clorox bottle, must be spotted and avoided. (It is no use for the lookout to
say “lobster pot ahead” as a warning. Rather, if under sail say, “lobster pot spotted, hold
course,” or “head up,” or “bear off,” as the case may be. If under power say, “come to
starboard” or “come to port.”)
Charts
I suggest using the Imray Iolaire charts A11, 12, 13 and 131. I made these based on
NOAA’s published charts, an unpublished US Navy survey of 1902, and a copy of a
DMA chart of the eastern half of Vieques unavailable to the public, as Vieques was then
a naval base. Sales of these paper charts have dropped off as Puerto Rican sailors
evidently rely on electronic charts, so Imray no longer corrects them. However, two
years ago I carefully reviewed the updated NOAA charts against the Imray Iolaire
charts. Buoy characteristics have changed, the deep-water channel to Ponce and the
turning basin in the harbor have been dredged, and Sunbay Marina has been
established north of Fajardo, but everything else seems to be the same as on the Imray
Iolaire charts.
Sailing directions
From Puerto Real head south two and a half miles to Boquerón. Enter the harbor via
Canal Norte, thus avoiding the Bajo Enmedio shoal. Head for the northeast corner of
the harbor, avoiding Roca Velásquez and also the two five-foot coral heads that are on
the Imray Iolaire chart. Explore the pleasant town of Boquerón for a couple of days.
The following day you do not have to start dawn as you do not want to be at the
eastern end of sheltered water and leaving through the gap at the north end of Arrecife
Laurel before 11:00AM, when the sun is high. Leave Boquerón about 9:00 through
Canal Sur. You’ll be sailing dead downwind, a so rig a main boom foreguy preventer so
you do not have an unexpected gybe.
When the harbor is cleared, head south along the coast but watch the fathometer.
Stay in two fathoms of water to avoid shoals off Punta Aguila. Once clear of the shoals,half a mile south of Punta Aguila is a isolated shoal which should be well to the east of
you when you head for Cabo Rojo.
Once you have rounded Cabo Rojo immediately head close inshore, right up on the
beach. It will now be about 11:00. The wind has probably switched to the east, but even
if it’s blowing hard you’ll be in sheltered water and should only have a small chop. Work
your way eastwards, passing inside all the reefs and favoring the shore, as it is easier to
pick out shoal water rather than the isolated coral heads near the reefs. As you
approach the gap at the north end of Arrecife Laurel, start the engine and motorsail
through the gap.
LA PARGUERA
Work your way eastwards until you find the buoyed channel into La Parguera.
Anchor and enjoy; the village, offshore islands and cays are within easy dinghy
exploring distance. You can also visit the bioluminescent bay — considered one of the
best places in the world to see bioluminescence — in your dinghy. This is best done on
a night when there is no moon. Overnight anchorage in the bioluminescent bay is not
recommended because of tourist boats and mosquitoes.
You can have another lazy morning at La Parguera, as exiting the reefs before the
sun is high is not a good idea. Get underway at midday and work your way eastward
inside the reefs, and then exit the sheltered water through the gap in the reef east of
Arrecife Enmedio.
CALETA SALINAS
Your next anchorage will be at Caleta Salinas, off the white hotel. This is a rolly
anchorage so anchor bow and stern facing into the swell. It gives you an excellent early
departure point for a choice of points east: Caña Gorda, the anchorage east of Punta
San Jacinto, or Ponce.
Leave Caleta Salinas at first light. Go far enough south to clear Arrecife Baúl.
CANA GORDA
Then continue east until your longitude is approaching 63°53. Look inshore and find
a hotel with peaked-roof buildings: Copamarina Beach Resort at Caña Gorda. Bring the
buildings to bear 017° magnetic. Run in on this bearing, threading your way through the
reef and coral heads, and dodging one isolated coral head once you have passed
through the reef. Anchor off the hotel, which in the past has been most hospitable.
ANCHORAGE EAST OF PUNTA SAN JACINTO
Alternatively, proceed just a bit farther, and east of Punta San Jacinto there is an
excellent sheltered anchorage with good holding and a good beach to leeward. In the
southeast corner of the harbor in among the islands is a wonderful beach loaded with
tourists over the weekends, but fairly deserted in midweek. It is well worth a visit in the
dinghy. It would also provide a nighttime anchorage but being in among the mangroves I
suspect might be rather buggy.
PONCE
Or instead of stopping as above, continue on another 14 miles to Ponce. Stay
inshore to stay out on the westward-flowing current. Off Guayanilla on the inshore tack
keep a good lookout for reefs. As you approach Ponce you can pass inside Cayo
Arenas, tacking through and eyeballing for the deepest water. When we sailed Iolaire
through here in ’93 the fathometer showed 11 feet.
In the harbor of Ponce there are two shoals that are difficult to spot: Cayo Viejo and
Las Hojitas. Take bearings on the big crane on the pier in the commercial harbor to
keep track of your position to avoid the two shoals.
Work your way into the southeast corner of the harbor and anchor off Ponce Yacht &
Fishing Club (Club Náutico de Ponce). Be forewarned, the bottom is soft, gooey mud
with poor holding. Once sure you are not dragging, go ashore and introduce yourself to
the yacht club manager. Organize guest cards for yourself and crew, and ascertain if
there is space in the marina for your boat. Ponce YC is reputedly the most hospitable
yacht club in Eastern Caribbean.
There is also an excellent anchorage in two fathoms northwest of Buoy 7, which is
just west of the northwest corner of the commercial pier.
PONCE TO SALINAS
It is 18 miles from Ponce to Salinas. If you make a dawn departure you have a very
good chance of reaching Salinas with almost all the trip made in a light northerly or
northeasterly. Even if the easterly comes in, it will not be blowing hard by the time you
reach Salinas. Stay inshore, right up on the beach.
There is a reef off Punta Petrona. The chart shows a narrow channel with a sevenfoot
depth. If the sun is high enough and the light good enough for eyeball navigation
and you draw six feet or less, this channel can be used motor sailing with the jib rolled
up. This will keep you out of the sea, in shore, with a better chance of holding the earlymorning
offshore breeze.
Alternately, depart at 8:00 or 9:00AM and sail seven miles southeast to Isla Caja de
Muertos, pick up one of their free moorings, and enjoy a day ashore. The next day
make an early morning departure and sail 12 miles to Salinas, which you should reach
before the offshore breeze dies out.
SALINAS
Salinas is an excellent harbor with an easy entrance. The controlling depth of the
channel is seven feet all. Deep draft boats should proceed slowly so if you accidentally
“park” you can back off. The channel into Salinas and the bay is all soft mud and sand.
Within the harbor the general depth seems to be about ten feet. There is an excellent an
excellent anchorage in 12 feet of water immediately west of Punta Arenas. This
anchorage is within easy dinghy distance of Marina de Salinas.
Marina de Salinas (www.marinadesalinas.com) is an excellent marina offering all the
facilities one has come to expect. The staff will be able to tell you what is available in the
area.
From Salinas take a dawn departure, as it is 18 miles to the anchorage just west of
Punta Viento, an anchorage that must be eyeballed.
When leaving Salinas, head southeast, noting the buoys while continuing east,
exiting at Boca del Infierno. Then continue east hugging the shore and hoping that since
you left at dawn you are sailing or motor sailing on a light northerly or northeasterly.
WARNING: Four miles east northeast of Boca del Infierno you will see the buoys
marking the entrance to the commercial harbor of Las Mareas. The shoal Arrecife
Mareas extends one and a half miles eastward from these buoys.
Once clear of the eastern end of the reef continue close inshore, passing inside the
five-foot spot 0.6 miles due south of Punta Barrancas. Also pass inshore of Arrecife
Algarrobo, which should be easy to spot, and Arrecife Corona, which may be difficult to
spot. Pass inside Arrecife Guayama and continue east inshore to the eastern corner of
Puerto Patillas.
PUERTO PATILLAS
NOTE: What follows are the sailing directions we were given in 1993. They worked
fine then but the marks have probably changed. Hopefully someone can come up with
better piloting directions to the inner cove where we anchored. We found ten feet with
the white splotch of paint on the retaining wall bearing 030° magnetic with the southeast
of the point of the harbor bearing 125° magnetic. Exploring with the dinghy rediscovered
that only 50 yards to the south east of us the water shoaled.
The sea hooks around the point and sets a swell into the bay. We left our yawl’s
mizzen up to minimize the roll. Sloops should anchor bow and stern facing into the
swell.
From Punta Patillas, you have a number of choices for your next anchorage. You
can stop at the Yacht Club marina at Palmas del Mar (www.theyachtclubmarina.com),
but it is only 32 miles from Punta Patillas to a good anchorage on western end Vieques,
with its numerous harbors and coves to explore.
AFTER PUNTA PATILLAS
Leave the anchorage at first light, heading north toward shore, then west into you
feel you can turn south and clear the reefs to the south. Once clear of them, turn east.
Hug the shore 12 miles to Punta Yeguas then try and hold a course of approximately
080° magnetic to an anchorage south of Punta Boca Quebrada with its beautiful white
sand beach.
VIEQUES
Five miles to the east of Punta Boca Quebrada is the town of Esperanza on
Vieques.
When entering Esperanza harbor leave Cayo Real to port and enter in the center of
the channel. (Unless you draw five feet or less do not try to pass between Cayo Real
and Vieques as there is no more than six feet of water.) There is roughly eight feet of
water in the channel and in the majority of the basin.
Puerto Mosquito just to the east has excellent phosphorescence and a perfect
anchorage at the mouth of the harbor. You are behind the reef, perfectly sheltered from
the sea but cooled by the breeze. There is good snorkeling and a white sand beach all
within swimming distance, so no need to launch the dinghy.
From Vieques to Marina Puerto del Rey (https://puertodelrey.com) on the east coast
of Puerto Rico is easy course to sail — approximately north for 13 miles. The marina is
huge and has all the services one would expect, including a major hauling facility. If you
have crew departing or arriving, transportation to San Juan airport can easily be
organized.
Heading north you can pass inside or outside Isla Piñeros. If passing inside consult
the back of Imray Iolaire chart A141 for the sailing directions for Pasaje Medio Mundo.
Iolaire has successfully used this passage, twice southbound, twice northbound, by
paying strict attention to these directions.
Detailed piloting and sailing directions are in Street’s Guide to Puerto Rico, Spanish,
US and British Virgin Islands (1995) available as a print-on-demand facsimile edition at
iuniverse.com or as secondhand originals from Amazon.
See “Eastern Puerto Rico: Stop Over or Stay” by Joan Conover in the May 2021
issue of Caribbean Compass at www.caribbeancompass.com/online/
may21compass_online.pdf


Mid-Dec 2025 to January 2026

We will leave Sakura in Puerto Rico or the BVI, and return home for the holidays, and then fly back again, hopefully with one or more family members in tow for New Years' eve and early January.   

This from Ronnie in response to my question regarding the ideal location for a Christmas layover:

Buenos días Dave!

Considering your crew will fly to Curacao Nov 29, most probable you will be sailing N around the first two week of Dic.

During winter, the odds of getting a weather window with SE winds are very slim.

That said, most probable you will be sailing somewhere to the S coast of PR.

Don’t know if you have been in PR before; but if not, I strongly suggest to your the Island at least one week.

Ah, don’t forget to pre fill your departure from Curazao and entry to PR using the SailClear app.

OK, now to the main topic: Where to leave your boat during your 10 days holidays.

If you can afford around $1,500 to leave your boat in a marina, that will be my first recommendation.  But the main issue is not economical, but to find a slip in any marina.Try first Marina de Salinas, which is next to our property or Ponce Yacht & Fishing Club (PYFC).

An alternative will be to anchor your boat in Salinas and ideally to pay somebody to check it periodically.

And as said before, once in PR, it is easy to make your way East to the VIs.

NOTE:

There are about 4@5 marinas in the E side of PR but they are more expensive and more difficult to get a slip.

If you are lucky to get a SE wind for the crossing N and end up in the VIs, there are more than half a dozen marinas there.

I will never leave my boat anchored there.

Sailing E from PR (including Culebra and Vieques) to the USVIs, you DON’ T have to check out NOR check in!

Hope all this info  helps!


Cruising the BVI

The BVI are a bustling sailing destination, and quiet, secluded anchorages are not its main attraction. Bellamy Cay is adjacent to the Airport, and a handy spot for coming and going, Nanny Cay marina and Sopers Hole marina are options at increasing cost.   
Moorings are reserved with an app called "boatyball"..

Jan 2026

BVI and then to Angulla, St Martin, etc... 

Departing the BVI would likely involve the longest (but still short) passage in the Antilles, at around 90NM.      


And after that?

Meander South, enjoying the gaining of sailing experience, the comings and goings of friends and family, and the people and culture of the islands.   

At the end of the Caribbean sailing season, May 2026, decisions must be made, as Sakura must be out of the path of hurricanes.  
.



Meander south.  

To be continued.


https://shell-storm.org/repo/Sailing/Pilot-Charts/atlantique-nord/



Friday, 4 April 2025

FleetOne antenna relocation & new composite antenna mount.

Composite antenna mount.  


The Cobham Sailor Fleet One Inmarsat system was an 'add on’ by the prior owner. The antenna was mounted atop a Scanstrut pole and its two struts (forming a tripod), all of which was wedged into the cluttered transom/cockpit area. One of the struts obstructed the port side cockpit locker lid, preventing it from opening fully. There were other additions, including solar panels, mounted in the shadow of the a wind generator, which reduced their output by 50%. As you can see in the photo,  Sakura was bristling with high-tech and no-tech clutter. (The photo reminds me a bit of the Apollo lunar lander model I had as a kid.)   In an effort to simplify things I have removed both the wind generator and the satellite antenna's scan strut pole, along with several other items,and am re-thinking the various parts and pieces and how the entire collection can be more coherently integrated.  When the boat is reassembled I will post before and after pics.  

As already stated, Sakura was equipped wth a Cobham sailor FleetOne satellite telephone and Redbox router.   I had been advised that this system was out of date and decided to replace it with the  cheaper, faster and more popular Starlink.  I have since reconsidered this and will retain the Inmarsat system, and use it for emergencies, weather, and minimal messaging.     

Revising the Antenna mount.

The FleetOne antenna is fairly compact and at 2.6kg is not terribly heavy.   After some thought, I decided to mount it on a platform bolted to the arch and extending forward far enough for the antenna to clear the solar panels. (The stern light is at the rear and must remain unobstructed)   While at the boat I templated the curve on the top of the arch so I could construct a fitted composite bracket at home.  

There were a few things to consider in designing the mount:

  • it must be compact, lightweight, and adequately stiff and fatigue-resistant as the antenna is a mass perched at the end of a lever that subject to constant cycling..  
  • The antenna mounting area is flat while the other end must conform to the curve of the arch, where it will be secured with the 4XM8 through-bolts that had previously secured the wind generator's mounting post.   
  • The solar panels reside above where the bracket will mount, so the bracket must be low-profile enough fit beneath them.
  • There should be access to the wiring opening on the top of the arch, which will be covered by the bracket, otherwise future access will be quite inconvenient.  This may not matter much in practice.   I will prepare by making a curved panel that can be secured as a cover.   
  • The installation should be simple, require zero maintenance and not look like a DIY effort.  

With all that in mind, I decided to use two layers of  a honeycomb core material called Nidacore, sandwiched between mulitple layers of biaxial stitch-mat, laminated with epoxy resin.  (Nidacore is not ideal for this, but I had some on hand)  Construction is kinda' like one of those hazelnut wafer cookies that shouldn't be good, but is.   

After making a form from some scrap, the various alternating layers were progressively laminated.    The Nidacore layers were beveled at one end to conform to where they  landed against the transition to the curved section, and this bevelled area was bedded/bonded with very thick glass-filled epoxy putty for strength and to ensure no voids.   . (This is the where the stresses from the constant flexing will concentate).  The 'glass was tripled across that area as well, but otherwise runs end-to end for strength, including a lamination between  the two layers of Nidacore,  The exposed edges were filled with dense glass-filled epoxy putty which was smoothed and radiused, then glassed over twice by wrapping the edes of a final bottom layer of stitch mat up, and then this overlapped with the top layer down around the entire perimeter. .In the photos you can see some carbon fibre tape laid into both sides beneath those final layers of stitch mat.   No reason for this other than I had some on hand, as one does, but it likely adds to the stiffness.  (and will make the boat go faster)  Before the final laminations were done,  the antenna mounting  holes were laid out and bored oversized, then filled with putty and pilot drilled.  Finally, reinforcing discs were fastened where the mouting bolts bear.    It will require some trimming to fit and will therefore be painted on site.  I will use 3m 4200 to bed/adhere it to the arch for extra security and to prevent it from shifting/wandering.  


 


Dimensions of the antenna below.  One thing I should have provided for but did not, is the mounting footprint of the slightly wider Starlink antenna.   Making an adaptor is pretty straightforward, but less elegant..  


 .   



Wednesday, 2 April 2025

Battery Installation and Victron Lynx Application

Battery/Bus Installation Complete

In 2024/2025, Saukura received a fully upgraded battery and distibution setup.  

See here for the battery selection criteria, and my experience purchasing LiTime batteries.  

Some minor tidying to do yet, but the installation is essentially finished.  The improved lid in place.  It's surprising how small changes can have a major usability (and therefore safety)  impact.  I was able to find M6 stainless steel-shafted knobs and these will be used to secure the lid, making it toolless.  Hefty screw-fastened  cable tie mounts repace the earlier type, and the hefty releasable cable ties used are not trimmed, making operation and retrofit much easier.       


After a one-week customs delay, the Victron Lynx assembly and battery hold downs arrived.  The existing cabling was dismantled, consolidated, repaired and reassembled.   Several runs of trunking were eliminated, several cables consolidated, and unused stuff removed.  All cables were labelled, and proper fusing was incorporated adjacent to the batteries.    It all works well and is much tidier and safer.  As it was before, It would have been very difficult to troubleshoot, and should that be necessary, I am now extremely familiar with the setup.
 The cumbersome battery box lid was cut in half lengthwise, and an inward-turned aluminium angle was added to each half to capture the outward-turned flange of the battery box.  It now requires only two bolts per side to secure the lid, and these will be made tool-less by replacing the m6 screws with threaded screw-knobs.      The batteries and compartment can now be accessed by removing two screw-knobs, and half of the lid, from either side.  Electrical work requires opening the portside only, and there is equally accessible storage on the starboard side.  .
Installing the internal hold-down beams and rewiring.

Basics of the new buss system

Negative 12VDC battery connections 

Start and house batteries share a ground connection in the battery box which connects the Lynx Shunt's main ground bus.   All other ground connections are made on the "other" side of the lynx shunt, via the Lynx distributor.   
The common battery ground appears to be how the factory connected the batteries, though the main battery switches open both ground and positive sides on two banks. (two batteries, four switches)   This seems at odds with the shared ground at the batteries, and would seem to risk ground currents reaching the hull via the engine.  (though the MD-22 is supposedly isolated from its electrical system)      I will need to confirm that the engine ground is isolated from the hull, and diagram the switching.

Positive-side connections 

The two house batteries are connected in parallel, and the positive side is connected to the Lynx Shunt's 1000A main bus  via cables less than 2' in length.  The Lynx shunt contains a 250A fast CNN fuse, and is bolted to the 1000A bus of the lynx distributor, which breaks out four seperate fused connections and their negative cables.   To these, are connected:
  1. The main house panel/loads
  2. The 1600VA multiplus 220v/70A inverter/charger
  3. The 800W 125VDC inverter
  4. The Alternator (via an ORION DC:DC charger)  
The Linx distibutor (a Power In with fuses added) has an M8 bolt at its end, two which the two marine breakers are connected, one for each of the "renewable" power sources, solar and SailGen.  The -ve sides of these are connected to the -ve side of the bus, via the BMV'712 smart shunt.   

Repurposing the BMV12 and its shunt.

The existing Victron BMV712 battery monitor was  made redundant by the installation of the Lynx shunt.  Fortunately, the BMV 712 can be reconfigured as a current monitor.  I had planned for this, and had drilled and tapped appropriate holes for the shunt  in the lexan  mounting plate. (in the photo below, you can see holes below the breakers)   The BMV 712 now serves as a current monitor for "renewable" energy sources, and measures the sum of energy being produced by the Hydrogenerator and the solar panels.    

Incorporating the Alternator.  

The stock alternator (either 50a or 70a, not sure) is externally regulated using a Sterling Power Products unit, with start and house banks originally isolated by a split-charge diode.  This appears to have been the stock arrangement.  This diode has now been  bypassed and the alternator, via the Sterling regulator, is connected directly to both the start battery and the Victron Orion 12/12-30 DC:DC charger, which is in turn connected to the Lynx distributor ( to charge the house bank).  The DC:DC charger  now provides the battery isolation previously provided by the split charge diodes, without the voltage drop penalty.   

Some helpful reinforcement from Ben at Stering Power.   

Alternators, when charging a lithium battery, urgently require current
limiting between the two. Without something to taper back the current and to
actually sustain a healthy continuous supply from the alternator we would
often see alternators running at full load for prolonged periods of time-
which inevitably can lead to alternator damage.  Even if the battery bank
was only 50% discharged, we could be seeing the alternator running at full
yield for over three hours, and frankly I've seen alternators practically
glowing within one. 

And when asked about incorporating the DC:DC charger:

2) Yes, this is the recommended approach. If the user needs more power, the
BB1240 would be an excellent consideration and is also more or less the
limit on what I would recommend for a 70A alternator.

I've read that unfortunately the Orion DC:DC charger runs as "hot as the Devil's dick".  An overtaxed alternator would however run even hotter.  It is obviously preferable to run each device within its respective operating limits, which is now assured.   The Orion can only provide a maximum 30a to the house bank, (which can accept much much more) and hopefully this translates to a resonable sustained load on the alternator.  I beleive the ORION can be programmed to limited the current further if necessary.   Hopefully a coooler-running, more efficeient DC:DC charging technology will become available, however in this application I am happy to accept that the alternator is not sized to "fast charge" the LiFePo house bank, and am quite willng to live with the conservative 30a ceiling.   .   .

Powering the water maker

I ultimately decided that the simplest solution was to install the 12VDC Seawater Pro water maker up forward and to power it via the existing anchor windlass circuit, which happened to be sized appropriately..  .

Earlier Posts

Components of the buss and battery hold-down setup. 

 

The battery box on OVNI 435 #6 measures 22.5" X 30.25"X 9.5" deep and is located below the cockpit.  It is made of welded aluminum and is bolted in place. It has an outward turning 2" flange around the top, with a seperate, single-piece plywood lid,     With the lid removed, the batteries are partially accessible from either aft cabin, with all electrical connections on the port side.    (note - OVNI 435 battery boxes can vary in size)

The one-piece plywood cover is secured to the flange with machine screws and easily-dropped nuts, and it has a 2"X2"  (approx) cleat around its perimeter.   The cover is bulky and inconvenient, and access is more difficult than it needs to be.  Fortunately, this can easily be improved.

Cables enter the battery compartment through randomly-drilled holes on the port side.   There is no positive bus bar, and no fusing at the batteries,    Over time, accessories with a mishmash of fuse styles (or none) had been stacked on the various battery terminals. none labelled, most with no means of disconnect.  The cables intrude into the middle of the box, interfering with battery installation and removal.   

The house bank's 4 group 31 batteries were connected in parallel with heavy, well-made jumper links that appear to be original equipment.   With the limited clearance to the conductive cockpit sole above, caution is required when working here, especially with top-terminal batteries.  

The starter battery was/is also in this box, furthest aft.  Access is particularly inconvenient.   

The photos below show:

  • how access is restricted by the cockpit, 
  • how the cabling was installed and intrudes into the box.
  • The many live connections that must be made in an awkward, confined space.    

Below left you can see that batteries must be placed in or removed from the box it in a fore and aft orientation.  Below right shows a pair of terminals in the cockpit locker that were connected to the starter battery.    Presumably this was to provide for boosting or charging.  This DIY hack has been removed, and I will eventually relocate the starter battery to a more accessible location, probably in the port side cockpit locker. 



What to do?

  With the upgrade from 4 group 31 to 2 group 4d (ish) lithium batteries, it became a necessary to re-think the stowage of the batteries, and opportune to incorporate a bus bar, circuit protection, and a safer, more orderly layout.  

Scope

  1. determine battery orientation  ensuring:
    1. optimal use of space, 
    2. minimal wiring
    3. tool-less method to install/secure/remove batteries. (small ratchet straps?)
    4. must be easy to reconfigure with - at most - basic woodworking tools.    
    5. Battteries must be well secured
    6. Ideally, either house or start betteries could be removed while leaving the others in place.
  2. design/install distribution and circuit protection for current uses and future expansion
    1. Likely this means locating the bus bar and fusing outside of and adjacent to the battery box for better access, however it must then be protected from accidental contact.    
    2. it should be easy and safe to disconnect each battery while leaving the other(s) in use.
    3. a ATO/ATC "blade" fuse block may be required for some low-current accessory connections.   
  3. Improve the cover
    1. Cut the existing cover in a fore and aft direction. 
    2. Incorporate a tool-less means of securing the cover so that either side can be quickly accessed. 
    3. Ensure that terminal fuses can be inspected and replaced from the port side.   
  4. Incorporate storage into any unused space if possible.
  5. Insulate the interior sides of the battery box to reduce the risk of contact with a live conductor.
  6. Provide clearly marked storage for spare fuses nearby.

The Physical part - Thinking inside the box.


Due to the size and shape of the batteries and the restricted access to the box, satisfying the above critieria is trickier than it first appears.  Particularly item 1.6, as the batteries must be placed in the box in a fore-and aft orientation  and then rotated atwhartships if that is the intent.  This creates a bit of an assembly puzzle.   See below, the mdf mock-up of the box and batteries.  


I cut a thick rubber mat to size and placed it in the bottom of the battery box.  This provides some cushion to the batteries, and will help prevent them from sliding.  I ultimately decided to arrange the batteries as pictured above, with a hold down system made of stout oak rails, with two 2" wide rails at either end of the box, elevated off the bottom by 2".  In the photo, mock-ups of these can be seen at the narrow ends of the box. Note that the postive terminals are at what will be the forward end of the box.   The 2" rail width was chosen to provide a protected space for cables and terminal fuses around the perimeter of the box.      

A second pair of rails, 2"X2" and movable, span the full 30" length of the box.  In use, these are placed in the empty box, and slid under the raised. fixed rails.  The fixed rails thus prevent these movable, longitudinal rails from lifting.  The batteries are placed between the longitudinal rails as pictured, and against the forward rail.   Ratchet straps looped around the movable rails are used secure both house and start batteries.  As the strap is tightened, The rails are pulled upwards and towards eachother, and the batteries, between these rails, are pushed downwards against the rubber mat.  Once the start battery is installed, wooden spacer blocks will be fitted into the remaining spaces to further secure the movable rails (and therefore the batteries) laterally, preventing any movement, and spacers will be added to the to the lid to further limit movement should the ratchet straps fail.   

No tools are required, and the layout can be reconfigured as required in future. 

Parts of Oak  

The mdf protoype worked well, so a more refined version was committed to red oak.     You can see the short end rails with the M8 bolt holes, and the movable rails with the added refinement of a cleat to secure the hold down strap.  The straps were cut and loops sewn as shown.




Below you can see how the movable rails and ratchet straps engage the fixed rails to secure the batteries by pressing them downward into the rubber mat on the bottom of the box.    Filler pieces will be fitted on site to further restrict movement of the rails.   Also visible are some additional refinements to the rails. 

Ready to be packed and shipped!  The long rails are oriented as they would be in the box.



The Electrical Part - Safe and Simple?

Circuit Protection at Battery box


Based on the info above and the cabling already in place, the following circuit protection should be incorporated. 
  1. Battery 1 terminal fuses @150a
  2. Battery 2 terminal fuses @150a
  3. Inverter charger 1600w/70a (100A)
  4. Small inverter.  (40A)
  5. 70A Alternator via smart regulator (verify cable, regulator output)
  6. House loads (125A per dwg, s/b fused already - where?)
  7. Future water maker (100A circuit?)
  8. 200W (450W future) PV (50a)
  9. 200W Sailgen (50a) 
  10. Wind (50a)  **  The wind generator may be retired.
That’s a lot….  Too much in fact.   It will be consolidated.

Bus bars, circuit protection and monitoring

After having purchased the necessary bus bars and circuit breakers to upgrade the DC distribution, I struggled to design a safe and compact electrical layout that would work in the limited space available.  This brought me back to Victron, and their Lynx bus bar range.   I had previously ruled out this system as being too expensive, but, all things considered, it isn't.  Relatively few additional components are necessary with this system and it has an inherently safe design.   
While the Lynx Shunt wasn't absolutely necessary, it provides the opportunity to further consolidate components.   The Lynx Power-In has been "hacked" to incorporate fuses (google it) and now functions as a Lynx distributor .(minus the LED blown fuse indicator)  The fuses (and breakers) are of a type and rating to protect the cabling in the event of a dead short, they are not intended to protect the equipment.     (Fuses are a topic worth investigating.)    Two thermal breakers were added and provision was made for an additional Victron smart shunt to monitor non-GX compatible charge sources.  
The components were arranged on a piece of 3/8” polycarbonate that will be fastened to (or very near) the port side of the battery box.  The polycarbonate was drilled and tapped for M5 allen head cap screws, to secure the Lynx devices, two thermal breakers and a future Victron smart shunt.     Clearance holes were drilled for M5 screws which will would be tapped into the battery box to mount the entire assembly.   These screws will also secure mounts for releasable cable ties to secure the cabling running below the lynx devices.

 Below you can see the space around the perimeter of the batteries and the oval holes at either end of the battery box for the battery cables, which exit the box and  connect to the adjacent bus bars (red and black covers in the photo.)  There is very little cable exposed.  
There is room for a third house battery if required but the removable hold downs might require some minor revision.   
There are fuses on each battery terminal and a very fast fuse in the lynx shunt.  
Load and charge source cabling will enter at the bottom of the Lynx power in, where it connects via a fuse to the bus bar.  The Lynx shunt is located between all grounds and the battery negative. 

Hopefully I can simplify and remove some of the massive amount of cabling and trunking that runs beside the battery box. 

There are two less-than-ideal aspects to this approach:
  • one of the house batteries must be removed to remove the start battery.  (I will relocate the start battery at some point)
  • There is no means to externally disconnect each house battery.   This means that an unused battery cable would remain live unless first unbolted from the bus.   While this is not unusual, and can be accommodated,  battery disconnects or external fuses might be more convenient than terminal fuses.   








Notes

Fuses required 

CNN350DIN.   Fast fuse for dead short, in lynx shunt.

Mbrf for terminal fuse disconnect battery.  There is a problem here in that either end of the wire will remain live.  For disconnect it should be at the lynx shunt.  
Mega (50.8mm) fuses within the lynx shunt.  
Littelfuse makes mega/AMG fuses as low as 40a








 
















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