Answers to questions on cabin sole treatment, the right spinnaker, batteries and safe charging
THE RIGHT CABIN SOLE FINISH
Q: I am working on refinishing my cabin floorboards. I have brought them home and sanded the old finish off and would appreciate comments on using varnish or polyurethane for the sole. — Danny Love, Grand Rivers, KY
DON CASEY REPLIES
Polyurethane is the better choice for a cabin sole. Oil-based varnishes are too soft. Keep in mind that any gloss finish on the sole can compromise footing, particularly if the sole becomes wet. That said, the beauty of a varnished sole has for me trumped traction reduction for four decades without consequence. That is not due to good luck, but rather to good handholds and a perpetual appreciation of the risk.
NEW BATTERY CHEMISTRY
Q: My tender motor takes 12 volts to start, and after a long winter the battery is usually toast. It is heavy, too! Any new battery technology out there for small-motor starting ? —J. Reynolds, Boston, MA
GORDON WEST REPLIES
New technology has arrived, and it’s called Lithium Iron Phosphate. Imagine an 8lb, 12.8-volt sealed LiFePO4 battery rated at 30Ah that can handle 60 amps of quick starting, can take up to 6 amps of recharge, and has built-in current protection and under/over load protection. Best of all it won’t blow up like your laptop, will take 2,000 charge cycles and works great in the cold! Yes, it’s more expensive than AGMs, but this new technology is excellent for marine applications. I use them myself. You can learn more at bioennopower.com.
MAYBE AN A-SAIL?
Q: My wife and I are planning on buying a spinnaker for our Alberg 35. The boat has a spinnaker pole and rigging for a symmetrical spinnaker, but we are wondering if buying an asymmetrical spinnaker would make more sense. — Emme Barkley, Miami, FL
BRIAN HANCOCK REPLIES
It really depends on the kind of sailing that you do—or are planning on doing. If you just knock around daysailing, then I think that an asymmetrical spinnaker would be a better choice. They are very easy to set and douse, and you don’t have to mess around with rigging the spinnaker pole and running the lines. On the other hand, if you are planning to sail offshore, especially in areas where there will be steady winds
from astern, then a symmetrical spinnaker would be my first choice. Once you have the sail set and pulling, you have much more flexibility with a spinnaker set on a pole. You can bring the pole aft and bring the spinnaker out from the dead air behind the mainsail. This enables you to sail deeper downwind angles; something that can be a challenge with an asymmetrical spinnaker. Sure, there is some hassle setting the sail, but if it’s going to be up for an extended period, a few hours or days even, then the extra effort will be rewarded.
DO NOT CONNECT?
Q: I am a sailor and also a volunteer fireman. Our department acquired a surplus Coast Guard 26ft Zodiac RIB. The boat has a placard next to an inlet that goes to a battery charger and breaker box that states: Do Not Connect to Dock/Ground Shore System; Connect Only to Ungrounded Shipboard System. I assume that this has to do with galvanic corrosion, but I am not sure. The hull and deck of the boat are aluminum, and due to deck plates that are not sealed tightly, there is usually some water in the bilge. We have put the boat onto a floating dock with a Hydro-Lift. We are working on running the electrical to the dock and would like to plug in the battery charger on the boat. Any information you can supply as to how to run the wiring that would avoid any corrosion or other problems would be appreciated. — Nowell Maluski, East Lake Buchanan VFD
NIGEL CALDER REPLIES
I could do with a bit more information. However, there are two issues involved here: protecting the boat against corrosion, and protecting people in the boat and in the water around it from electric shock. Without knowing how the boat is wired I can’t make specific recommendations, but I can make some generic suggestions. First, make sure you have a marine battery charger and not an automotive one. Marine chargers are built around isolation transformers that enhance their safety. Second, I recommend you find a way to fit a 30 milliamp (mA) ground-fault protection device into the shorepower circuit. If you have a regular shorepower inlet in the side of the boat, you need something called an electric leakage circuit interrupter (ELCI) installed in the boat’s wiring immediately after the shorepower inlet (for example, check out bluesea.com). If you just run an extension cord to the battery charger, you need ground fault protection in the shorepower cord. (If you do a Google search for shorepower cords with ground fault protection you will find offerings from the likes of Marinco and Hubbell.) Either way, a ground fault protector senses any leakage current that could cause an unsafe condition and shuts down the circuit. Finally, if you do have an onboard electrical system that consists of more than an extension cord to the battery charger and you are going to plug into shorepower when the boat is in the water, you should install something called a galvanic isolator (you want a “fail safe” model) in the AC grounding wire close to your shorepower inlet. This minimizes the corrosion risk. As you can see, this gets quite complicated and has significant differences from shoreside electrical installations. If there is any doubt, I strongly recommend you consult a marine electrician! s