Originally Posted by GreggL
Having a bit of a speed issue here. Some are saying that my hull not being clean will produce noticeable results. My boat was commissioned in march and has been in the water
since then. Is there some way of cleaning
the hull without hauling? Is this even necessary? IOW, will a hull get dirty enough after a few months to warrant a speed change of over 2 knots? If not, then I may have an engine
or prop problem...
I responded in your engine thread and will elaborate a bit more here.
Again, you are an experience powerboater and powerboats are designed with "excess" horsepower and are not as sensitive to fouling.
Sailboat engines are as small as possible to predominantly save weight.
Sailboat hulls are very efficient and need to be to go places under sail.
Most boats will use an "ablative" anti-foul. Basically it is a "soft" paint
that has some chemical in it, some copper usually and these are designed to inhibit critters. However with changes in environmental rules the amount of chemical is reduced these days.
Plant growth also happens and if the boat is sailed often the "scrubbing" action of the hull through the water helps shed the anti-foul over time, taking the "plant growth" with it.
My observation is most weekend boats don't move enough for ablative paints to be as effective as they could be. So most owners as Bash says hire someone to dive and "wipe" the anti-foul on a periodic basis. You will figure out over time what works best for you and your waters.
Eventually the ablative paint is worn off. The chemicals are largely gone, the barrier coat is largely worn out and where you could wipe every 2 months, now you get growth and real barnacles
within 4-6 weeks. This is time for haulout and new anti-fouling
There are a zillion zealots for their own particular brand of anti-foul. Where I am I am happy with Micron Extra.
The prop - I have not figured out how to protect the prop. It fouls quickly and anything applied to it wears off almost immediately. There are really expensive prop coatings but I just make sure I dive the prop and clean it often.
When my boat loses 1-2 knots of boat speed the prime suspect on my boat is the prop and my prop can get fouled in our waters in as little as 3-4 weeks.