On Sun, 24 Jan 2010 14:41:09 +0100, "Edgar"
wrote:


"Bruce In Bangkok" wrote in message
.
snipped
.
Which does not mention the electronic method which makes one wonder
about the validity of the claims for the "sound system".

I seem to recall that this system was based on observations which showed
that the transponders of echo sounders remain free from fouling.

Transducers convert electricity to sound, in this case. Which is what
your meant. Transponders pick up an signal and send out a reply. They
have them in comsats. IFF uses transponders.

Casady

On Mon, 18 Jan 2010 07:21:16 -0600, Vic Smith
wrote:

On Mon, 18 Jan 2010 18:38:26 +0700, Bruce In Bangkok
wrote:


Has anyone tried any of the anti-fouling schemes intended for
propellers, and if so what was your experience?

The question comes about because I just had to dive on my prop and
clean it. When I got down there I discovered a mass of "clams" as big
as a bushel basket. Took two days to scrape them all off.

True, for one reason or another, the boat hasn't moved in the better
part of a year but still I don't believe I have ever seen as much
growth. Must be either global warming or high CO2 content :-)

In any event, it does make one think "there must be a better way".

Haven't tried it because I don't have a boat.
But you made me think that if you knew your boat would be idle a long
time, wrapping the prop it in a old piece of poly tarp might work.
Maybe even a thick black garbage bag.
Should be easier to put that on and crack/cut it away than spend 2
days scraping.
Barnacles need some light to grow, right?
We sometimes want a patch of lawn for garden and the easiest way
to kill the grass is to lay something on it that blocks the light.

Barnacles are animals, not green plants, and they don't need light.
They need food and oxygen and the bag would cut off both.