Ultrasonic antifouling?? any good??

[Paul L]

I don't know the particular fouling in your canal, but the cold water of the Puget Sound is not that aggressive. Trinidad SR worked very well for us for years in the Sound. Once we got to the tropics it was marginal, at best once, as it aged a little.
That's the problem with interpreting ultrasonic, or coppercoat or any bottom paint. Every area offers different challenges. Weve been in places that your bottom will be fouled in a few weeks, even with new bottom paint. Cartegena comes to mind.

[senormechanico]

Bobatkins,

You also installed a cheapo system with TWO emitters on a 41 foot boat.
How many square feet of bottom do you have, and what's your displacement?
It's a heck of a lot more than my 5200, now more like 6,000 lb displacement with
FOUR HIGH MASS transducers and much more sophisticated design.


Apples and Oranges.


You want Apples and Apples? Look at the pics I provided.
Same dock space, same state, same water, same boat, different years.
I'd call that fouling I showed rather "agressive". It sure slowed down the boat !


If you want to find out about high mass transducers and effectiveness, the internet is your friend.
Are your emitters mounted in PVC pipe fittings?
Mine are in thick gauge aluminum and each weigh a few pounds.


The difference is similar to having a good sea water ground for a HAM or Marine SSB, or a good bolting to the side of a swimming pool for a diving board.
This high mass allows the ultrasonic signal to be actually transmitted efficiently to the water instead of just vibrating in place.

[leftbrainstuff]

New Zealand Department of Primary Industries published the results of a broad assessment of marine cleaning options back in 2015.

It's titled 'In-water cleaning technologies: Review of information Prepared for Ministry for Primary Industries'. Section 4.2.3 summarizes a single ultrasonic test that found the technology ineffective. https://www.mpi.govt.nz/dmsdocument/10814/send

The New Zealand example is only a single small test so extrapolating the results is not scientifically rigorous.

As an engineer I am familiar with ultrasound technology and cleaners. I am surprised that the vendors have not obtained independent scientific evidence to support their products.

I suspect most hulls / installations are not sufficiently rigid at the useful ultrasonic frequencies and therefore scientific validation is difficult to obtain.

Reading the marketing material from vendors like Sonihull they all mention working in conjunction with existing hull treatments. The market opportunitty is to make obsolete bottom paints completely.

[fstbttms]

Originally Posted by senormechanico

Look at the pics I provided. I'd call that fouling I showed rather "agressive".

It’s pretty clear you have no real concept of what “aggressive fouling” looks like.

[Sputnik]

I am sending this enquiry to some Ultrasonic companies:

Hi,
I have a Hunter 356 (35.5ft GRP bilge keel sailing boat) which is moored at Brightlingsea Creek, Essex, Uk and am considering this system for antifouling.
The water here is high in silt content, if I leave my mooring lines in the water for a week they are covered in silt slime. I used Coppercoat antifouling on the hull which is completely ineffective in preventing fouling. The slime attaches to the hull, and presents an excellent medium for weed (of different varieties depending on the time of year) to grow on. I find I need to dry out to scrub off about every 6-8 weeks. The weed/growth is easily wiped off with a squeegee or pressure washed off.
The boat is on a mooring, so will need Solar power to drive this system.
Will you system work in this environment?
If I buy it and it doesn't work will you refund me?
Regards,
Neil

[Pete7]

Neil, good luck, but results from others in the UK aren't encouraging and that is being powered by mains shore power.

You might blast the odd barnacle off, but it's the green weed and soft corals that are the real problem. You could a try a spell of playing Motorhead through some speakers in the bilges.

Pete

[Sputnik]

100% satisfaction guarantee!
The trial works as follows...
Install the system to your boat and if after 6 months you are not completely satisfied with the performance you can return the system and we will refund you your money*.
* See site for full terms and conditions
* Installation Kit Non Refundable

Ultrasonic Antifouling

Their reply:

Hello Neil.

Thank you for your enquiry and interest in SonicShield.

The situation you describe is not something I have ever come across (other than with tidal berths that dry out). The concept of antifouling as you know is to remove the food source for fouling. When silt is present in the water this creates the food source. The fact that the weed is easily removed would suggest the CopperCoat is doing a job and ensuring the growth does not permanently attach to the hull. Adding SonicShield to the protection (it is common for customers to have both copper coat and SonicShield) will only improve the situation. With the fouling situation you describe no one single antifouling product is guaranteed to work and hence the reason you should considering adding SonicShield as a back up the copper coat.


Watch this space!

[fstbttms]

Originally Posted by Sputnik

Their reply:

Hello Neil.

Thank you for your enquiry and interest in SonicShield.

The concept of antifouling as you know is to remove the food source for fouling. When silt is present in the water this creates the food source.

Caveat emptor, Neil. This guy doesn't display a good knowledge of how and why fouling occurs.

[Sputnik]

I have had some correspondence from Ultrasonic antifouling UK who have seen photos of my hull from various years and seasons, and tell me they have seen similar fouling elsewhere in the UK where their system has helped reduce the fouling levels. They advertise that if you are not completely satisfied then "money Back".....

Ultrasonic Antifouling

I believe that some systems work better than others, and also that because fouling is so varied throughout the year a multi-pronged attack may work. So once I have installed some more solar panels which I also need for extended cruising (I am on a mooring) I will try this system next year and report back.

Thank you for all the feedback from your own experiences.

Neil

[Sputnik]

Gosh, 3 years and how time flies.......bzzzzzzzzzzz!
I installed 300W of solar panels not long after my last post, which I have found work well and support both fridge/freezer/lighting etc when we are cruising. So I am now in a position to fit US antifouling, as the Coppercoat is not protecting the boat. Now the water is warm (about 20-22 deg C) the fouling is terrible. In one month I had the same amount of fouling as 7 months through the winter.
So I am about to bite the bullet and see if it works......I had hoped upon revisiting the forum that someone may have updated their experience, sadly not.
I will let you know.
Neil

[Tillsbury]

Hello three years later poster ��. I installed my system (home assembled Jay car dual kit for about $300) three years ago after the boat was newly antifouled. Recently a diver in the marina cleaned my boat for the first time since then, he reported that it looked more like 12-18 months of fouling, not three years. He changed the shaft anode, so it's looking like I might last another season at least before hauling again. The savings in extending what is a $3000+ operation to haul and repaint is more than good enough for me.

Not that I know that it makes any difference, but the diver's opinion was pleasing

[fstbttms]

Originally Posted by Sputnik

Gosh, 3 years and how time flies.......bzzzzzzzzzzz!
I installed 300W of solar panels not long after my last post, which I have found work well and support both fridge/freezer/lighting etc when we are cruising. So I am now in a position to fit US antifouling, as the Coppercoat is not protecting the boat. Now the water is warm (about 20-22 deg C) the fouling is terrible. In one month I had the same amount of fouling as 7 months through the winter.
So I am about to bite the bullet and see if it works......I had hoped upon revisiting the forum that someone may have updated their experience, sadly not.
I will let you know.
Neil

Clearly your experience with Coppercoat didn’t teach you to be able to spot snake oil

[Paul L]

Originally Posted by Tillsbury

Hello three years later poster ��. I installed my system (home assembled Jay car dual kit for about $300) three years ago after the boat was newly antifouled. Recently a diver in the marina cleaned my boat for the first time since then, he reported that it looked more like 12-18 months of fouling, not three years. He changed the shaft anode, so it's looking like I might last another season at least before hauling again. The savings in extending what is a $3000+ operation to haul and repaint is more than good enough for me.

Not that I know that it makes any difference, but the diver's opinion was pleasing

Are you saying that a boat that looks like it had 12-18 months of fouling on its bottom is a good thing?

[tkeithlu]

Testing ultrasonic antifouling would be a pretty simple experiment, with plates that were and were not "protected" in the same locations for the same time. But instead, all the manufacturers present are "testimonials" of no value whatever. Major dealers like West Marine and Go2marine have not offered products. While the lack of research and lack of market are not conclusive, they certainly are red flags that this is mouse milk.

To my knowledge barnacles have not even the barest of vibration detectors. I can't think of a logical reason that they would decamp if exposed to vibration at any frequency.

[Sputnik]

I didn't use the outfit I posted the link to as they have removed their "money back guarantee"..........quel surprise!
Still enjoying scrubbing off about every 6 weeks during the summer. Part of the issue in Brightlingsea is the temperature of the water, on the ebb the water temp' is around 20-24 deg C, with loads of sediment in the water which looks brown.