Hull Cleaning

[mbianka]

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...
Thanks!

Gregg:

I sail in the LIS area and because of some recent work commitments have been off the boat for several weeks. You can get a look at what I found when I finally got back on board a few weeks ago:
THE BIANKA LOG BLOG: PROP TALK
My prop was extremely fouled as I expected. The boats bottom had a heavy coat of slime and some marine growth but, compared to the prop was relatively clean. I dive and clean the prop and bottom a couple of times over the season. If you have not cleaned the bottom and prop since you launched yes you will have some speed issues especially if the prop is encrusted with barnacles. The best way to keep the bottom and prop clean is to keep the boat moving but, sometimes that is not always possible.

[fstbttms]

Originally Posted by Sailmonkey

...it really depends on your local waters.

100% correct. As true for fouling rates as it is anti fouling paint effectiveness. Very region-specific.

[Ex-Calif]

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...
Thanks!

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.

[GreggL]

That's great info. I appreciate the help.

[hugosalt]

In western Long Island Sound I currently have bottom cleaned on monthly basis...I haul boat and paint every year.
Growth is specific to very local conditions. Different conditions, as stated above, along with currents will result in varied growth
within small distances.
Hi chance if in water since March and bottom has not been
cleaned that growth on prop is primary reason to losing
your 2 knots....The water is warm take a swim and check it out
bring a scraper...then have your bottom cleaned.
You will most likely get your 2 knots back.

[GreggL]

Had my hull and prop cleaned out by a diver last week. The issue with speed still remains and I'm sure it's not a mismatched prop because this is a new issue.

[Dulcesuenos]

Originally Posted by GreggL

Had my hull and prop cleaned out by a diver last week. The issue with speed still remains and I'm sure it's not a mismatched prop because this is a new issue.

Just curious did you see them cleaning it? Did you snorkle down and inspectvtheir work ?I have known some cleaners who maybe hit the waterline an nothing else. This is why i do my own when it needs it.

[Gelfling]

I would rule out mismatched prop if this just started to happen. I would dive myself and male sure prop is clean. If it is........you might want to check the shaft alignment.

[GreggL]

Guess I'll be going down myself. The diver came highly recommended from the marina I'm staying at.

[Gelfling]

Originally Posted by GreggL

Guess I'll be going down myself. The diver came highly recommended from the marina I'm staying at.

Then just go ahead and check the alignment on your prop. It won't hurt to make sure it has a good alignment. I am with you.....not a fan of being under my boat either!

[foxpro]

Hello!

I also have my Sailboat in a slip near Kemah, TX and all I get for the most part is slime if it gets to bad I will Dive on it and simply wipe it off. I bought the boat about 2 months ago, cleaned it when I got it and it's just now getting to the point where i'm thinking of doing it again (If the fish don't clean it first )

[DivingOtter]

For future reference, Im always around and we dive year round.

[psk125]

Is the 2 kts speed difference under power, sail, or both? Crud on the prop can make a huge difference under power. Is it a folding prop? Blades that aren't fully deployed - because a barnacle is growing in a hinge point where a diver can't reach- won't push the boat very well. Folding blades that are being held open by mussels work as brakes too. Perhaps the speedo is getting decalibrated somehow because of vibrations, and so making it look like you're going slower. We notice about a quarter knot difference under sail between having a clean bottom and one with three week's growth. When we wet-sailed a Soling, (no bottom paint) we hauled it every week to keep it clean in Long Island Sound. Stuff grows faster in cleaner water, and it's a lot cleaner around here now than it was 20 or 30 years ago.