Do you have to coat your props? No. But, should you? YES! Prop coatings help boat and yacht owners get the most out of their vessel by improving performance and fuel efficiency. By preventing growth, or allowing the growth to be castoff, the boat can more easily run in the proper RPM range. This reduces the stress on the motor and allows the boat to more easily run at the proper cruising speed. Finally, prop coatings allow for greater fuel efficiency. By having prop coatings you are allowing the props to operate more efficiently which, in turn, reduces the drag caused by the build-up of growth. Marine fouling raises your gallon per minute burn which results in poor fuel economy.
So, now you know why you need to coat your props but which coating is best?
As we mentioned, propeller coating helps prevent marine growth from accumulating on the blades of the prop. There are really only two options when comes to coatings; antifouling coatings and foul release coatings. The difference between the two is in how they work.
Antifouling coating relies on chemicals to keep growth build up from occurring, This generally takes the form of paint with cuprous oxide (copper) being the inhibitor of the growth. The higher the amount of copper in the paint the better it works. One of the pros of paint is the cost compared to other coatings as well as the ease of application. It can be applied with the props and shafts on the vessel and typically by the contractor painting the vessel. Just make sure that the surfaces are properly primed before painting. A few of the cons to mention? Painting does not allow for the growth to be cast-off as with foul release coatings and the props must be scraped to remove the growth that does accumulate. Also, paint is prone to damage from scraping and will be eroded away as the vessel is used.
Foul release coatings are a bit different. They have no antifouling properties whatsoever. There is no chemical in the coating that prevents growth. Foul release coatings work by creating a very smooth, slick surface that will shed the accumulated growth while the vessel is in operation. When the prop is spun up the smooth surface does not provide enough grip for the growth to adhere and it is consequently “flung” off the prop. The downside to foul release coatings is that if the boat is not used and the props spun up on a regular basis the growth will adhere and damage the coating. Aggressive cleaning will also scratch the surface and provide the necessary grip for the growth to adhere. There are generally two types of foul release coatings:
Etched metal top coated with a polymer base. We have worked with two different brands; PropSpeed and PropGlide. Both work in roughly the same manner and come with both pros and cons. Pros - The propeller and shaft do not need to be removed from the boat for application. Cons - Cost of application and durability. The topcoat is delicate and manual cleaning can easily damage the coating causing scratches and gouges.
Hard, baked-on coating is a durable finish that is baked onto the propeller. The one we are most familiar with is Muscle buster. Pros - Durable and less vulnerable to damage from cleaning or abrasions. It holds up better and, is therefore recommended, for boats or yachts that don’t see a lot of use. Cons - Components must be removed and sent to an application vendor for coating. This isn’t so bad for props but if you want the shaft coated it is no small feat to remove the prop and send it to the applicator. We have also noticed that this coating seems to suffer from harmonics forming after the coating has been applied which will require the filing of the props to eliminate.
If you have any questions, we welcome you to give us a call! 561-408-8042
You can also visit our website for our Propeller Removal, Installation and Coordination of Repairs services as well as all the services we provide.
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