Details and Some Cruising

September 6, 2018

I have always wondered how I could get a charge to the thruster/windlass battery in the forward part of the boat when it’s away from shore power.  Making it a part of the main bank would require a long run of heavy gauge, very expensive wires.  I could pull power from the main batteries with one of the new 12-volt to 12-volt chargers, but that would be expensive, too, and I would like to keep the systems separate.  The great performance of the new Go Power solar panel made the final decision pretty easy — another, smaller panel up forward on the cabin roof.  It’s only a 10-watt, but after you’ve used the thruster or windlass, you have hours and hours while underway for it to recharge. $50 at Defender.

I anchored last night at Duck Island near Westbrook, Ct, and after pulling in about 80 feet of chain and rode, I really couldn’t see much voltage loss at all after only a few minutes on the panel.

— The exposed wiring tying together the AIS, radio and MFD display always bothered Ray, so I finally got around to covering it with a cherry box and split loom.  Looks much better.

— The steering and engine controls protrude into the head, so I made removable boxes to cover them.

— There all kinds of expensive 12-volt fans for boats, but they have to be hard-wired, and finding ways to hide the wire runs on a small boat like Tardis is hard.  But I saw some USB-powered fans on Amazon and since I have USB ports all over, they should work just fine.  They are not as powerful as the dedicated fans, but I have three of them and they seem to provide plenty of air movement.

— Search Google for “float switch problems” and you will get as many search results as “cute kitten picture.”  Float switches that turn the pump on when the water reaches a certain level just never seem to work.  I changed them out on Memsahib every two years after a couple scary episodes.

I was giving the decks a good spray last month, which always puts water in the bilge.  Float switch dead — one year old.  So now I am trying a device called a “Water Witch” which the Coast Guard now uses.  It uses water to close an electrical circuit and start the pump.  So far, so good.  In fact, I had to raise it a quarter inch because it was actually TOO sensitive and was activating when running the boat, which always puts about a quart of water sloshing around the bilge due to spray from the cockpit.

Took a short cruise with John to Mystic and Watch Hill over Labor Day.  15 knots and tide on the nose, which made for a 2-3 foot chop, but the boat handled well, even though we only made 8-9 knots (which became 14 coming home).  Tardis is a light boat, and it’s going to be pretty jumpy in a chop.  But it very seldom pounds, which is always scary because as the boat becomes a bass drum you wonder if your glasswork is as good as you thought it was.  Chines seem to keep rolling down, too.  Maybe we lose a half-knot and a little fuel efficiency, but the boat runs much smoother with full gas and water tanks.

I think my fuel efficiency is much better than what my instruments are showing.  Over the last couple days we’ve run about 50 miles in 5 hours, and I just filled the tank we were using with 20 gallons.  The instruments are showing just under 5 gallons per hour and 2.2 miles per gallon, when it looks like we’re actually running 4 gallons per hour and 2.5 miles per gallon.

Actually had just been in Mystic on a short trip on a Corsair F31 25-knot screaming, high-tech trimaran (which we motored all the way in no wind).  Seeing her tied up next to the 200-year-old whaling ship Charles W. Morgan was ironic, but then again wasn’t, since the wind is still the wind, sails are still sails and sailors still go ashore in Mystic in search of rum.

Solar panel for thruster and windlass

Box to hid AIS connections

Split loom in front

Boxes to hide rear of steering and throttle gear in the head

USB-powered fans

The Water Witch — let’s hope this works better than float switches

After 33 years as a Mystic Seaport member, I pulled rank and got the best slip in the place — a floating dock right in front of the heads and restaurant

Pat Harris’s 25-knot trimaran “Gypsy Heart” in among the tall ships at Mystic. (Steve White photo)

3 comments on “Details and Some Cruising

  1. Ross King
    September 12, 2018 at 3:58 am #

    I was wondering about a similar issue regarding a forward battery to run a capstain and how to charge it. I’m not sure if the battery will last very long (age) with only the small charge the solar can provide. If you find it’s not sufficient I wonder if a VSR from BEP Marine would be the ticket? You wouldn’t need any heavy cable, and it would only provide juice once your start battery is full.


    • ton
      September 27, 2018 at 11:23 pm #


      I will give you 5 reasons why I opt for the ‘big cable’ solution for the Olga I help to build here in NC.
      #1. Technical: Nigel Calder debunks the ‘thin wire and VSR’ theory on p.54 (4th ed.) of his Boatowner’s Manual. In short, with running engine, the alternator will try to fully compensate the voltage drop of the battery when used. So you have to size the ‘thin’ wire to accommodate full alternator amperage.
      #2. Financial: I estimate Paul’s solution (Group 27 wet cell starting battery, restrainer, battery switch, solar panel and controller) on at least $300. For that money, you can run 100″ AWG1 Red and Yellow Ancor Cable. See ABYC E11.
      #3. Economical: A Wet Cell Battery needs periodical maintenance (check electrolyte level, replenish) and eventually needs replacement. Cables do not need any of that.
      #4. Practical: With a Group 27 battery, you put an additional 50+ lbs. in the bow. Forever and ever. Batteries do not get lighter when empty.
      #5. Safety: Sulfuric Acid and Seawater form lethal gasses. If not mixed with salt water, the battery produces Hydrogen. You want that in an unvented area that has only a 3″ mattress to separate sleeping persons from any of that?

      Make a wise decision.


    • memsahibsvoyage
      September 28, 2018 at 1:23 am #


      Tom’s comment reminded me that I didn’t get back to you on this. What I forgot to mention was that my A.C. charger can handle three banks, so the solar panel is only for use on the hook. On the dock, the batteries are always topped up by the charger. I have a separate meter on the front battery and so far the 10 watt panel is keeping it at full voltage w without shore power. I looked hard at the VSR when setting up the whole system, but finally decided I wanted two independent battery systems in the boat. If everything goes totally to he’ll with the start and house batteries, there is a nice, big fully charged Group 27 up there that I can pull out and use for anything.

      I like to baby the house batteries and hate pulling them down with a big load from the thruster or windlass. And distributing the weight of the electrical system along the length of the boat helps with trim, especially with my big engine.

      As to safety, it’s a big, well-ventilated area up there. If saltwater ever gets to that battery, it would mean the boat has sunk, which would be a bigger problem.


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