Choosing the right antifouling paint
Choosing the right antifouling is crucial for your boat's long-term protection against marine growth, algae, barnacles, mussels, etc. We've all tried to take the boat up in the fall and thought, "I should have looked into antifouling a little more." It's actually not that difficult to choose the right antifouling if you just take a little time to familiarize yourself with it.
The first thing you need to do is find out what TYPE of antifouling your boat has now. It can be a bit tricky, but if you spit on your finger, rub it over the antifouling on your boat and it stains, then you most likely have self-polishing antifouling. If it doesn't rub off, then you have Hard Racing or a thin film antifouling, such as VC 17.
Below we have just tried to list the different types of antifouling, so that it is easier for you to find out what you have on the bottom and tell you a little about the advantages and disadvantages of the different types. You can really only use advantages and disadvantages if you are planning to give your boat a bottom treatment and are starting from scratch. The overriding starting point is that you should always paint your bottom with the same type of antifouling as before. It does not have to be the same brand (Hempel, International, Jotun, etc.), but it MUST be, for example, self-polishing on self-polishing.
The relationship between price and quality
Price and quality of antifouling are inextricably linked. The reason is that there are some substances in antifouling that are quite expensive - including, for example, copper. Copper is expensive and the more copper there is in it (and other biocides), the more effective the antifouling is. If you lift a 2.5 liter high-quality antifouling you will notice that it is very heavy. Often 2.5 liters of quality antifouling weighs up to 4-5 kg., because there is so much dry matter in it and that is what makes it effective.
Types of Antifouling:
There are different types of antifouling, each with its own characteristics, as well as several brands with unique formulations. In this in-depth test, we will explore four main types of antifouling and evaluate several prominent brands to help you make an informed decision.
Self-polishing Antifouling Paint:
Advantage: Self-polishing antifouling gradually releases active substances, ensuring constant protection. It is a type of antifouling that is really easy to work with. The bottom must of course be high-pressure cleaned when it comes ashore, but then you can paint a new layer on top. If you buy a quality antifouling, you can almost be sure that there will be no growth on it when you take the boat ashore.
Disadvantages: There are several disadvantages to self-polishing antifouling. Since you paint a new layer on the outside every year, new layers are automatically built up and after some time it will start to peel off. There is nothing dangerous about your self-polishing antifouling peeling off, but it can affect speed and fuel consumption. That is why many people choose to scrape or blow it all off and start over with primer and new antifouling every 5-15 years. Another and very significant disadvantage is that it is HUGELY ENVIRONMENTALLY DAMAGED - there are biocides in the antifouling and they harm the environment (and you, if you are not careful.)
Test result : Ideal for boats that move regularly (typically under 50 knots) as it maintains efficiency through use.
Our good advice: BUY QUALITY PRIMER - THIS IS HOW YOU AVOID HEADACHES
Hard Racing Antifouling:
Hard Racing or hard antifouling types are made for boats that sail fast or that want a completely smooth bottom. The antifouling type is not as effective as self-polishing, but that is the trade-off for having a smooth bottom.
Advantage: Hard racing antifouling is known for its tough surface and high speed performance. It is reasonably effective, but requires a lot of sailing.
Disadvantage: In reality, you have to sand the boat lightly every year, as the outer layer of Hard Racing is "dead" and therefore you have to go down to a layer where there are still active biocides. This is again an antifouling paint that harms the environment and has biocides in it, which is not good for you and the marine environment.
Test result: Excellent for racing boats that require minimal friction and optimal performance.
Thin film primer (VC 17m, VC 17 m Extra and similar):
Thin film treatments and thin film bottom paints have been used for many years. If you take a walk in the harbor in the spring you will see boats that have a nice copper-colored bottom. However, this color changes quite quickly when the boat is put in the water and will become graphite-gray instead. These are boats that have been given VC 17m, which is a very popular type of bottom paint - especially among racers, etc., as it gives a completely smooth bottom
Advantage: Thin film antifouling, such as VC 17m, provides a smooth surface and prevents algae growth. The more you sail, the more effective the antifouling is.
Disadvantage: There are many biocides in thin-film antifouling paints and therefore they harm the marine environment (and you) - in addition, you should probably expect this type to be phased out in the future, as it is environmentally harmful.
Test result: Suitable for fast boats as it reduces friction and is effective in mild waters.
Biocide-free Antifouling Paints:
As the new biocides directive dictates the amount of biocides in antifouling, you should expect the traditional antifoulings listed above to be phased out. That is why many are switching to biocide-free antifouling types. Most major antifouling manufacturers are offering biocide-free alternatives, but Hempel is probably the one with the longest experience. They have developed a silicone-based type for commercial traffic and have further developed it for pleasure boats. Many mistakenly believe that this is a new technology, but it has actually been used for over 10 years.
Advantage: Biocide-free antifouling paints use alternative technologies to reduce environmental impact. Many of the products are 2-year products so you only need to treat the boat every other year. In addition, the friction is very low, so many experience a reduction in fuel consumption and higher speed.
Disadvantages: It requires that you familiarize yourself with the products and process when switching from traditional antifouling types to biocide-free, environmentally friendly antifoulings.
Test result: A sustainable solution with varying efficiency depending on sailing conditions and water quality.