Give or treat yourself to a subscription to Boats in Motion print + digital and for only 39 euros a year you get the magazine at home plus read it on your PC, smartphone and tablet. With a sea of advantages.
Pilot automatic, on-board tools, AIS, Radar, voltage regulator. Do you know all the tricks to make them work best?
1. WHAT ARE THE TRICKS TO MAKE BETTER USE OF AUTOPILOT?
The autopilot is the best companion for navigation at night as well as during the day. It can be used in so many ways, toward a waypoint, under sail, under power, with the angle to the wind, or simply pointing the course.
To use it properly it needs to be properly installed, so with the fluxgate compass, the autopilot’s own compass, properly installed, possibly amidships and away from magnetic sources. The hydraulic arm acting directly on the rudder shaft must be well sized so that it does not overstress and overpressure.
To use the full potential and functions of the instrument, it is good to have the network of on-board equipment working properly. This way you can select a waypoint on the Gps and have the pilot follow it directly. Similarly, if you wish to sail and want to relax without being at the helm, you can select the pilot-to-wind function. Choose the angle for which you have set the sails and select the sail autopilot function on the instrument.
This function is particularly useful if you are sailing with the wind at your back or otherwise in wide swaths to the wind, as it in fact avoids the risk of sudden and unintentional gybes, which are much more frequent if you are sailing with the pilot set on a course or waypoint. To sail with the autopilot, it is good to have a Gyro sensor, a kind of gyro compass, and a very fast processor. The former very accurately calculates the course and angle held even if the boat is heeled or stressed by waves. The second, on the other hand, analyzes the movement and reaction time of the boat and rudder. In this way, adjustments on the tiller angle are minimal and smoother.
2. WHAT TOOLS SHOULD I BRING ON BOARD
Basic tools are those to have on hand and at hand at all times: fundamental are a complete set of screwdrivers, wrenches, socket wrenches, Allen wrenches, large, good-quality pliers, as well as fine-nosed ones for miniature work. Don’t be short of a caliper, an iron saw, files and fine and coarse sandpaper. Pay attention that the keys are the correct size you need on board. An iron and rubber hammer and a tester are always useful.
The necessary for clear silicone, anti-mold and gun. SikaFlex is versatile and ideal for making elastic vibration-resistant sealants: after curing it can be sanded and painted. A set of wood glues, a universal glue and a two-component epoxy like West System. Electrical tape with the inner roll made of plastic and not cardboard, some cloth tape (gray tape), and a roll of Teflon, which is essential for replacing gaskets and eliminating small leaks from plumbing joints.
3. WHY DOES RADAR ONLY INTERCEPT METALS?
Radar antennas emit at a precise frequency an electromagnetic wave that is “launched” into space. By definition, an electromagnetic wave, once in space, creates a magnetic field and an electric field. When the wave encounters a metal and thus an electrically conducting material, the electric field generated by the wave short-circuits, thus ending its travel through space and being “reflected” back to the source.
If the wave encounters a nonconducting material, such as fiberglass, it passes through it, without any interference. But then how to “see” and “be seen”? What matters for the radar efficiency to be correct is the surface area of the reflecting object, which essentially produces an echo to the wave, as if it were a mirror.
For this reason, it is essential to equip oneself with a radar reflector, having the ability to be spotted more easily by a wave beam, even at a great distance. Such an accessory is much more useful for motor boats, since a ten-meter sailboat with its mast already has a reflective value of 10 square meters. Since the main dangers to boaters in the open sea come from intersections with ships, it is good to know that normally offshore they use a wave beam with a frequency of 3GHz, with a length of 10 cm for a range of about 24 miles.
Its accuracy in getting the details right is in the 10-mile range, so if you consider you are both sailing at 20 knots, you have less than 30 minutes to sight or be sighted. The larger your spotlight the more likely it is that a freighter will be able to identify you on time and especially clearly.
4. WHAT IS THE DIFFERENCE BETWEEN AIS WAVES AND RADAR WAVES?
The major difference between the two systems is the type of frequency that is used to scan portions of the sea. AIS adopts the frequencies of Vhf radio on a band around 100 MHz and uses the same antenna. These types of waves are called directives, that is, the transmitter and receiver must “see” each other.
However, this is not absolute; basically with AIS you get a signal from a boat even if it is behind an island. Radar, on the other hand, exploits microwaves, on a frequency as low as 3 GHz that, using perhaps an untechnical term, we can call superdirective. It means they do not cross obstacles as in the example of an island. However, radar waves are more powerful; they have substantially greater signal range.
5. WHAT IS A VOLTAGE REGULATOR FOR?
All marine alternators require regulation of the electrical output voltage, which is done by a regulator. Its job is to change the rotor current, which in turn energizes the alternator. By varying this current, the value of voltage generated by the alternator is changed and consequently the current delivered by it and sent to the batteries. Internal regulators often have a constant output voltage, without being able to change its value, and are used for engine batteries: in practice, as soon as the voltage rises above the preset value (about 14 V), the regulator blocks the supply from the alternator. For service batteries, a second regulator often comes into play.
It generates a voltage that is around 14.2 volts, and when the battery is fully recharged (normally an efficient recharge should take at least three to four hours), the voltage decreases to a value called maintenance. The value for liquid batteries is around 13.2 V, while for gel batteries it is about 13.7 V. The level of the holding voltage is regulated by the alternator and charger. For gel batteries, the consistency of the holding voltage is essential, because if lower it causes the so-called memory effect, thus compromising their service life. Then check the maintenance voltage level and if different from that recommended on the batteries, have it changed.
HELP US KEEP YOU UP TO DATE
The journalists of Motor Boats , together with Giornale della VELA and Top Yacht Design strive every day to ensure quality, up-to-date and correct information about the boating world free of charge through their websites. If you appreciate our work, support us by subscribing to the magazine. The annual subscription costs only 29.90 euros!
Also support us on SAIL Newspaper and Top Yacht Design!
Sign up for our Newsletter
Powerboats, its stories, from small open to motoryachts. Sign up now for our free newsletter and receive the best news selected by the editorial staff each week. Enter your email below, agree to the Privacy Policy and click the “sign me up” button.
At sea with top technology. Did you know that there is an American company that has eliminated the problem of tanks on board? With a buoyant system and a simple hose you can dive up to 5 or 10 meters
Excosystem is an all-Italian company with more than 50 years of experience in the safety sector, particularly at the forefront of fuel tank protection. It is in this context that their flagship product was born, an aluminum alloy grating that,
There is never enough power aboard modern boats, and in fact even those with small boats find themselves having to power – often – energy-intensive utilities. Voltab, an all-electric portable generator designed and made in Italy, is a smart solution
Is it time to change the outboard for the tender, but you don’t know what choice to make? Are you undecided whether to stick with the endothermic or, maybe try an electric? Today we show you two electric outboards for
Send us your sea photos and enter history with us! Your pictures will be featured on our “bulletin board” immediately.
