On Tue, 19 Jan 2010 19:36:34 +0700, Bruce In Bangkok
wrote:

On Tue, 19 Jan 2010 05:52:52 -0500, wrote:

On Tue, 19 Jan 2010 07:32:32 +0700, Bruce In Bangkok
wrote:

On Mon, 18 Jan 2010 16:28:05 +0100, "Edgar"
wrote:


"Bruce In Bangkok" wrote in message
m..

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".

Cheers,

Bruce
(bruceinbangkokatgmaildotcom)

Ordinary ablative antifouling might be better than nothing if you hardly use
the boat but it washes off in no time at all if you run the engine. I use
some expensive stuff in a spray can that Volvo produce for their underwater
units. This seems basically to be the same sort of antifouling but harder,
so it does not wash off so quickly. Also it makes a somewhat slick surface
so that barnacles find it harder to stay on while the prop is running.
I have a theory, not yet put to the test, that the very slick paint that has
been produced to make a wall graffiti-proof would be the way to go because
barnacles could not stick to it at all once the prop started to rotate.. The
reason I have not yet tested this idea is because the smallest quantity that
I have found for sale is about 10 gallons.


You are correct that normal anti-fouling paint doesn't stay on the
prop however several paint companies are making a paint specifically
for propellers. The recommended procedure is to (1) sandblast or grind
the propeller to a specific surface finish; (2) clean the propeller
chemically clean; (3) apply a specific primer and finally (4) apply a
specific anti-fouling paint. The whole procedure is involved and the
paint is expensive and apparently deviating from the specified
procedure results in failure. Thus my questions.

Cheers,

Bruce
(bruceinbangkokatgmaildotcom)

Normal anti-fouling should not be applied to a propeller. Normal
anti-fouling paint contains copper and your prop will get eaten.

I have no idea what the "propeller paint" is but it is certainly
recommended for propellers so I assume that it is compatible with
bronze.


I agree.