Ultra sound anti foul devices

[Huskybeer]

indeed there are some systems that do use only one frequency. the better system uses a varying frequency plus a very low power. given the hull specifics (GFK or polyester) and the usual hull shape the dispersion of the power is such that a few meters away no meadsurable disturbance should be expected for the dolphins. there are two sides of the medal. to use the u/s may reduce the amount of toxic chemical release in marine waters, a fact with which we will be faced over short or long period thanks to the "green" environmentalists, the other side is an eventual perturbance of marine animals dpending on snar for survival. however, once they detect a certain frequency they can consider it as a "threat" and stay away from it, or they get used to it and work their way around it (cerebral adaptation). I give to remind that the cavitation bubbles generated by the propellers generate an ultrasound waves that can be heard several miles away.

[Rustic Charm]

Thanks everyone. I've noted all the antidotal evidence doubting them.

I had kind of anticipated that by now there would have been some more specific data and research into them. Given quality units for a boat under 40 foot are not particularly expensive, I if they do work and do extend the life of a good anti fouling, then the $2k would be worth it in my book.

Can't seem to locate the comparisons Dockhead referred to.

I antifowled just last September and this year used Sigma ebrasive which is a common brand used on many commercial ships. It was 'cheap' and came in 5 ltr tins. After six months in our cold water I think the paint is feeding and encouraging growth. So, this year I'm hauling out again and I'm going to take it all back and put a better known quality on like International.

As I have a steel hull, a good quality ULtra Sound unit should work well, if indeed they work at all. But, whilst I acknowledge they have been around for 20 years they are still very much from what I can research a new technology. And given technology changes slowly in some aspects in the recreational world, then perhaps it's just not taking off yet?

And when talking about the 'engineering logic' behind them. I hear the same thing about ultra sonic pest controllers which are very popular over here. And I know that two years ago putting a Dead Sea gull on my boat for six months marked my boat. I've not had to do anything about birds for over a year now. Not a drop of bird ***** anywhere. But, few people anywhere think this works

[Huskybeer]

Rustic Charm. Having a steel hull is even better. make sure that the trransducers are strategically placed (take 1,5-2x the number recommended) and are bonded flush with as trasferring medium an epoxy containing silver.the thginner the better, eventually secure them mechanically as a precautionary measure. do not forget to apply/renew the antifouling paint, before you install the transducers. good luck. keep me posted

[hzcruiser]

Originally Posted by Rustic Charm

Thanks everyone. I've noted all the antidotal evidence doubting them.

I had kind of anticipated that by now there would have been some more specific data and research into them. Given quality units for a boat under 40 foot are not particularly expensive, I if they do work and do extend the life of a good anti fouling, then the $2k would be worth it in my book.

$2k is ridiculous for what's in the box and the transducers. I bought a kit from Jaycar here in Oz a few years ago with just one transducer for less than $300. It draws less than 100mA and is on all the time.

I wouldn't vouch that "it works" since there are too many other factors that have changed since, like different anti foul paint and different usage patterns. It certainly didn't make matters worse. Subjectively I noticed fewer hard growth at the haul-out this week than 2 years ago. Note that's on a steel hull. The biofilm also took longer before it started to grow noticeably.

I've read up before buying the kit and yes, there were people that loved it and people that called it snake oil. My take is that it can work better on some hulls and in some climates than on others. It's a matter of trying it "on yourself", but certainly not for $2k!

As a side note, has anyone tried the copper anodes approach, where you hang one each in front and behind the boat and let a small current flow between them?

[Nicholson58]

These things were reviewed in Practical Sailor a couple of years ago. They were unimpressed. The review placed it about with snake oil. If it really worked, we'd all know.

[hellosailor]

Some of them, if installed properly, appear to work against some types of critters and growth under some circumstances. Good luck trying to find any particular system that will come with a guarantee of performance, and explicit aid to ensure it is properly installed on your boat.


Overall, they seem to not work, but it looks more and more like some of them will. IF they're installed properly, which apparently is an elusive goal.


Even if I was sure I had "the best" brand and "the best" installation advice, I wouldn't buy one unless it came with a "satisfaction guaranteed" money-back guarantee.

[JAYEN1]

My sad experience is that Ultrasonic Antifouling does definitely NOT work.

[Rockyscience]

I am certified level II in ultrasound and unless you have a lot of power you can put this idea to rest, you may do better with hanging a fence charger lead overboard but don't get caught doing that, it would also be very bad on a metal hull... Active cathodic protection stops corrosion on metal hulls very well but does little or nothing for marine growth. The best thing may very well be the old hydraulic rotary brush and elbow grease... http://www.cruisersforum.com/forums/...lies/trash.gif

[Rustic Charm]

Originally Posted by Rockyscience

I am certified level II in ultrasound and unless you have a lot of power you can put this idea to rest, you may do better with hanging a fence charger lead overboard but don't get caught doing that, it would also be very bad on a metal hull... Active cathodic protection stops corrosion on metal hulls very well but does little or nothing for marine growth. The best thing may very well be the old hydraulic rotary brush and elbow grease... http://www.cruisersforum.com/forums/...lies/trash.gif

"Certified level II in ultrasound", in what field exactly is that?

[Rockyscience]

Electrical Reliability. As in asset condition monitoring. (Industrial RCM)
Rocky

[TOT]

Rustic Charm
We have installed the Cleanahull system from Cleanaboat and have 6 points of connection (3 on each hull) with 2 power boards and we have been running it for approx 13 months, we had nothing prior and having the boat berthed in Singapore in tropical waters we have seen approx a 60-75% reduction in barnacles, this is based on our observation only.

It is a very simple system to install and worth every penny as l have found the barnacle growth here is - 1 month in the tropics is equivalent to 12 months of barnacle growth in Melbourne, Australia.

The system does NOT reduce algae...

PS - The fish seem to be attracted to the sound and we find we have a lot of fish at anchor.


SV TOT 😃
Wayne

[senormechanico]

Originally Posted by Emerald Sea

I put a set of US system (Clean-a-Boat, Australia) on my previous 40ft boat based in the marine growth aggressive tropical waters of Singapore and it ran 24/7. There were two transponders and it was on for 2 years before I sold the boat. Easy to install. I'd say it was 95% effective with the occasional barnacle getting a foothold. Doesn't work around the water line of course.

This has been my experience in the PNW since I installed a 4 transducer version of the Clean A Hull system a few months ago.
I am on the third year of Micron Extra bottom paint and it is pretty weak now.
I am getting waterline grass, but my knotmeter never fouls.
It used to quit working after only a couple days of non sailing.
The ultrasonic system is definitely helping, even on my cored hull.
The real results will be known next spring when I repaint.

[Rustic Charm]

Thanks guys, that's the feed back I wanted to hear about as well. First hand from those having success.

I'm starting to think it won't be too successful over here in tassie, as its 'weed' I seem to be having the biggest problem.

[jtgarcia26]

To all the "un-believers":

Let me start by saying that I keep my boat in the water year round in the Chesapeake Bay, just south of Annapolis, MD. I currently own a 27 foot Ranger Tug and I purchased an ultrasonic anti-fouling system from west coast ultrasonics based in Canada and installed the system myself in October 2014. Eight months later (June), I pulled my boat out to trailer it to Ocean City, Maryland, for two weeks, and I had no "hard" growth on my hull. I was very surprised to see no barnacles at all.

A few weeks ago, with the threat of Hurricane Joaquin coming up the bay, I decided to trailer the boat again and bring the boat to the house until the hurricane passed. Once again, no hard growth/barnacles. What I do have is the soft growth that forms along the water line, but I have learned to take my soft brush and brush it off about every other week.

I must confess that at first I thought I was buying "snake oil", but I have been very pleased and delighted by the product. Since my boat's hull is less than 45 feet, I just need a dual transducer system. Boats up to 65' need a quad system and larger boats need multiple units. For a dual system, the cost is $950 / the quad is $1250, which is about the cost for hauling my boat out and re-applying bottom paint every year, but with this system, I haven't had a need to bottom paint yet. So not only is it cost effective, it's saving me some money as well.

You can read more about the product, the specs and my (along with others) testimony/pictures at the companies website: Index. As far as discomfort to animals, I have two labs that aren't bothered by the system and there are always small fish swimming around the boat when we are at our dock.

I know some folks are going off what others have said or read an article by someone who gave an opinion, but I'm here to tell you that the system works because it's on my boat and I've been using it for a year now. If you have any questions, I'll be happy to answer.

[RaymondR]

The kits are available from Jaycar for A$269.00. Should not be too hard to test, install one on a piece length of steel and hang it off the jetty for twelve months.