Ramona said...

Torch said...

ive been thinking of putting ultrasonics on my boat, J car have a do it yourself kit I have just ordered, let you know how it goes

These are extremely popular with the Poms. Do a search on Practical Owner's Reader to Reader forums. They have been importing them for a few years. Here are a couple of examples, there are dozens of pages on the subject. "Your results may vary".

forums.ybw.com/index.php?threads/jaycar-ultrasonic-antifouling-review.292064/

www.ybw.com/forums/showthread.php?t=258391

thanks for that romona, good read

I have been following this discussion like at lot of others as I am quite interested to see how it performs especially if it means longer time between haul outs and less regular antifouling etc.
It occurs to me however that whilst it might be great to not have to haul your boat out as frequently to re do the antifoul, would you not still have to haul out to replace anodes therby defeating the purpose. You may say just fit bigger anodes so they last longer, but that would make for a rather large lump of anode with a corresponding negative impact on performance.
Any thoughts?

MatM14 said...

I have been following this discussion like at lot of others as I am quite interested to see how it performs especially if it means longer time between haul outs and less regular antifouling etc.
It occurs to me however that whilst it might be great to not have to haul your boat out as frequently to re do the antifoul, would you not still have to haul out to replace anodes therby defeating the purpose. You may say just fit bigger anodes so they last longer, but that would make for a rather large lump of anode with a corresponding negative impact on performance.
Any thoughts?

Adding to what Ramona said, if you did not need to scrape, sand and apply two coats of paint, you could just consider an annual 30-min lift-splash that some yards offer for quick inspections. Would be enough time to check/replace anodes, and the cost is often a fraction of what it would cost to haul, set up and park for two days and drop back.

MorningBird said...

I have hard racing antifoul and now redo the antifoul every 2 years. After about 12 months I get a diver to give the hull a scrub. That lasts about 3-4 months when I get him to do it again. I then need to get it done once more and if needed replace the anode. Then it is time for a slipping and antifoul. Each scrub is $70-80.
I do clean it myself if the water temperature is amenable but he can do it quicker and better than me with a snorkel.
$1450 for the slip and antifoul, $240 for the 3 scrubs means $1700 every two years, $850 pa.

I know this question represents a bit of topic drift, but what the hell ... lets divert for a moment from the Ultrasonic option. Above, Morningbird summarised very nicely some of the benefits of Hard Antifouling. Now I have never used the hard stuff, so I'm thinking if it lasts that well and can be scrubbed, what's the downside/s of hard antifouling compared to ablative antifouling? Why doesn't everyone use it?

I know this question represents a bit of topic drift, but what the hell ... lets divert for a moment from the Ultrasonic option. Above, Morningbird summarised very nicely some of the benefits of Hard Antifouling. Now I have never used the hard stuff, so I'm thinking if it lasts that well and can be scrubbed, what's the downside/s of hard antifouling compared to ablative antifouling? Why doesn't everyone use it?

In our experince, we've found hard stuff works well (& is better for racing) if you live in a "low growth" environment, ie: on the ocean. Although we mainly race on the ocean, we are often based on the Swan River. The warmer water & high nutrient levels are a marine growth bonanza, and the hard stuff quickly gets swamped. We use ablative stuff instead.

Funny however, many of the offshore based boats also use the ablative stuff.

Poods

Good point.

Hi Warwickl.......we are following your progress with Cleanaboat ultrasonic anti fouling.....we live on the Gold Coast and are looking at installing this product on our IPS drive boat.
Hopefully this will help with the problem of growth......many products we found in Australia are very expensive to install....this could help.
We shall also let this forum know of our future progress.
Our boat is located at a pontoon mooring in one of the canal's.
Cheers and good luck!

Great to hear all is going well with your Riviera 3350.....our CleanAboat Ultrasonic Antifoul is now installed on our Regal 4060 IPS....sorry to hear about the crab pot!
They installed one 50 watt Transducer on each IPS and two extra 50 watt Transducers just forward of the drives.
So shall see how things go.
The boat went back in the water on Wednesday 17th Oct 2012

Hi,
How's it all going?

I was wondering if the effect would be increased if you used the ultrasoncic's while the boat was moored with a plastic skirt around the hull?

Keithw

I was sceptical but I am now thinking there might be something in it.

keithw said...
From the articles I've bgeen reading you need the vibrations from the ultrasonics so I guess keels being lead or iron and a denser it would reduce the ultrasonic effect?

Lead being worse than iron or steel as lead doesn't resonate, hence its use as sound deadening material. Ultrasonics being sound after all, just that we don't hear it ... hopefully only the targeted critters do.

My original concern with ultrasonic systems was whether the vibrations would eventually cause fatigue cracking somewhere in the boat structures. I was starting to believe I was wrong about vibration to the hull from the ultrasonic transmitter. Ultrasonics used in non-destructive testing of materials is only on for a few seconds.

I don't believe that there is any detriment to the hull or other structure resulting from ultra sonics whereas the same could not be said for E.L.F. or V.L.F. where I believe there exists evidence of structural failure, but this failure is usually also associated with sound pressures in the regions of 120db and above, not the sort of thing at all that you find commonly in boats. ......... Unless of course you were building a weapon

As I understand, if ultrasound works, than fishing boats never need any anti fouling considering
they constantly , cleaning hull with 3kW bursts plus return pulse
would have additional benefit to clean too.

Ultrasound has no damaging affect at all. It's one of the safest frequencies.
In hospital use ultrasound scanner to check unborn babys.

Extremely low frequency under 20Hz is damaging and destructive.
/some suggest that wind-turbines producing low frequencies /

14 Months since last antifoul and 7 months since the CleanAboat Ultrasonic System was fitted.

Here is a summary of the level of success since installing the CleanAboat Ultrasonic antifouling system.

June 2012 System installed about 6 months after last antifouling, so the boat had already been through 1 summer.

System installed included 2x 50 watt transduces bonded the hull floor directly over the propellers and 2 x 20 watt mini transducers bonded to the metal arms for each rudder

Mid October 2012 No new growth and any previous growth was dead and fell off with light scraping/rubbing – power supply working very well ie 200 Ah battery charged with an 80 Watt solar panel

December 2012 A quick inspection noticed white worm growing on the transom and some on the sides below the water line and all very much alive.

13 January 2013 I took some photos as attached. The white worms have died and now just mostly rub off, there is a lot of slime and a few (may be 6) shell fish here and there. The slime just rubs off with a hand wipe even though it is thick. I felt under to the trim tabs and they seemed to have some hard growth which I would think are dead white worms.

Note: Due to circumstances I have had little use of my boat, may be 6 hours running since June 2012 when the system was installed. The lack of use has not given slime and other bits the chance to get washed off this makes the test to date even more interesting in regard to its effectiveness.


General Comment: What seems to occur is that some shell fish and other forms of life like the white worms are still able to attach themselves however they die and are easily rubbed off. I expect with the normal boat use the slime and dead things would mostly wash off.

My experience rings true with the claims that the systems do not kill fish but only algae. The slime on the boat is dead algae so no longer a food source

Photos Comments: Photo of slime around the corner of the transom at the exhaust outlet, then hand wiped off slime photo shows the removal of some slime just by rubbing my hand over that corner section.

Swim Platform struts in June 2012 had significant growth and shell fish and I think it was in October 2012 all was dead so I was able to easily scrape them off. These photos show little to no new growth now and only 1 stubborn shell fish that is still alive.