Chart Plotting Tools and Inclinometers

Relying exclusively on electronics for navigation carries risks that should not be underestimated. Traditional chart plotting, done with nautical dividers and protractors, is the only method for verifying the position provided by the GPS or for planning a route with full autonomy. The accuracy of a plotting instrument depends on the stability of its joints and the rigidity of the materials: a divider that slips during use or a square that flexes can seriously compromise navigation safety.

The inclinometer also plays a key role, especially on sailboats or motorboats with narrow hulls. Knowing the heel or roll angle lets you better adjust weight distribution and anticipate the boat's behavior in rough seas. A well-positioned inclinometer provides an instant visual reading that no digital display can replace in terms of physical feel for the hull.

When choosing these instruments, always evaluate the construction material. Instruments made from technical plastic offer good resistance to the marine environment, while metal ones maintain superior rigidity over time. It is critical that the graduations are engraved or printed with high legibility, because at the chart table, possibly at night or in dim light, the clarity of the markings is a key safety factor.

Our technical support is available to clarify any doubts about compatibility or the specific use of each instrument. Before completing your order, check the divider span against the size of your nautical charts and verify the inclinometer's mounting system to make sure it is suited to the bulkhead or helm console of your vessel.

Selection criteria for manual navigation instruments

• Mechanical precision: Verify that the dividers have firm but smooth joints so the opening does not shift during use.
• Legibility: Choose instruments with clearly marked and high-contrast graduated scales for quick reading even in low-visibility conditions.
• Materials: Prefer anti-static plastics or metal alloys resistant to salt corrosion to maintain accuracy over time.
• Inclinometer mounting: Make sure the mounting base is compatible with the curvature or surface of the bulkhead where you intend to install it.
• Dimensions: Match the length of the dividers and squares to the actual working area of your chart table.

How can I tell if a nautical divider is reliable?

A functional nautical divider must have well-aligned points and an adjustable friction that keeps the opening constant. If the points shift under light pressure, the instrument does not provide the accuracy required for a correct position fix.

Is an inclinometer necessary on a motorboat?

An inclinometer is useful for monitoring lateral trim during navigation in rough seas or for balancing the load of tanks and equipment, helping prevent excessive heel that affects fuel consumption.

Are plastic or metal squares better?

Plastic squares are lightweight and less likely to mark the chart, but they can warp if exposed to very high temperatures. Metal ones are more rigid and durable, but require more care when handling to avoid damaging the chart.

How do I get support choosing the right instrument?

The Nautiba technical team is available to assess your specific needs. You can review the detailed product pages on the site and contact us to verify the suitability of an instrument for the type of navigation you practice.