Vancouver Island Marine Surveying Blog

  The condition of a vessel’s underwater profile is a primary indicator of its overall maintenance history. A "fouled" bottom is more than an eyesore; it increases hydrodynamic drag, compromises fuel efficiency, and can lead to engine overheating by obstructing raw water intakes. When choosing a bottom coating, owners must navigate the technical trade-offs between Ablative and Non-Ablative (Hard) paints. Selecting the wrong product for your operational profile can lead to premature coating failure or a costly "strip-to-gelcoat" restoration down the road. I. Comparative Analysis: Ablative vs. Non-Ablative Coatings The choice between these two systems depends entirely on how—and where—the vessel is used. 1. Ablative (Self-Polishing) Coatings Ablative paints are designed to wear away over time. As the vessel moves through the water, the outer layer of the coating "erodes," constantly exposing fresh biocides. Best Suited For: Coastal cruisers, seasonal boat...

  A common point of inquiry during marine surveys involves the presence of surface discoloration on bronze components—specifically the transition from a bright metallic finish to a blue-green hue. It is critical for vessel operators to differentiate between stable passivating films and active corrosive processes such as de-zincification. While the "pink" hue of de-zincification indicates structural compromise, the presence of a green patina is often a sign of a healthy, self-protecting alloy. The Role of Cupric Carbonate (Verdigris) In high-quality marine bronzes, exposure to a saline environment initiates a controlled oxidation process. This results in the formation of cupric carbonate , the characteristic green film often seen on thru-hulls and fasteners. Unlike de-zincification, which is a subtractive and destructive process, this patina is additive and protective . Once a uniform layer is established, it acts as a microscopic barrier that stabilizes the metal, significa...

  I was recently doing a sea trial and saw a lonely mast sticking out of the water.  This is a sobering reminder to inspect your underwater fittings as you get ready for the start of the busy cruising season. In marine surveying and naval architecture, the hose clamp is a critical mechanical fastener responsible for maintaining the water-tight integrity of the vessel. Failure of these components—particularly in raw water cooling, exhaust systems, or below-waterline penetrations—represents a primary cause of preventable emergencies. Inspection  An inspection goes beyond a visual check for "tightness" - look for the following:  Crevice Corrosion: Frequently occurring in 300-series stainless steel when deprived of oxygen (common in shielded or submerged areas), this manifests as dark pitting or a dull red oxide. Any sign of "bleeding" or staining requires immediate replacement. Mechanical Deformation: Inspect the "housing-to-band" interface. If the housing ...

  If you own a boat with a sail drive, there’s a critical piece of rubber maintaining your boats watertight integrity. As a marine surveyor, I’ve spoken with enough clients to know that the sail drive diaphragm (or hull seal) is one of the most overlooked preventative maintenance items on boats. Here is the reality: while saildrives offer smooth operation and easy installation, that rubber seal has a finite lifespan. Ignoring it isn't just a maintenance lapse; it’s a safety risk. What Exactly Is It? The saildrive unit passes through a large hole in your hull. To keep the water out while allowing the engine to vibrate and move on its mounts, manufacturers use a thick, reinforced rubber gasket. Some systems use a double-seal system . There is a primary inner seal that does the heavy lifting, and a secondary outer seal. There can be a water-sensor alarm fitted between these two layers to warn you if the first line of defense has failed. Service Life  Most manufacturers suggest r...

    As a marine surveyor working on the best coast, I’ve seen a lot of confusion lately regarding radio registration. While most Canadian boaters know about the MMSI (Maritime Mobile Service Identity) for their vessel, there is a newer, personal tool that is becoming essential for safety: the Maritime Identity (MI) . If you’re a commercial crew member hopping between tugs or a recreational kayaker exploring the Gulf Islands, here is what you need to know about navigating the National Maritime Information Database . What is a Maritime Identity (MI) in Canada? According to Innovation, Science and Economic Development Canada (ISED) , an MI is a unique nine-digit number that identifies you as an individual .   You can read more here Think of it like this: MMSI: Stays with the boat (the vessel's "license plate"). MI: Stays with you (your personal "maritime cell number"). It is programmed into your personal portable maritime radi...

    Ah, the MMSI. If you've ever stared at that "Distress" button on your VHF radio and wondered if it actually does anything, you’ve stumbled upon the most important safety tool on your boat. Think of an MMSI (Maritime Mobile Service Identity) as a digital fingerprint or a cell phone number for your boat. It’s a unique nine-digit number that identifies your vessel to the Coast Guard and other ships. In Canada, getting and managing this number is managed by Innovation, Science and Economic Development (ISED) Canada , and the best part? It’s completely free. Here is everything you need to know about setting yours up. Why Every Canadian Boater Needs an MMSI Without an MMSI programmed into your Digital Selective Calling (DSC) radio, that red "Distress" button is just a plastic flap. With it, the radio sends an automated digital Mayday that tells the Coast Guard: Who you are (vessel name and description). Where you are (if connect...