Bottom Cleaning and Annode Changing

[dnimigon]

I know there has lots on here about when to repaint and when to change the zinc annodes. I've searched things out on differnet site and still don't have a clear answer. Our boat is in Puerto Vallarta. We just bought it. A Mexican has been cleaning the bottom every month and the zinc changed on the prop shaft. It's a 30 ft. Catalina. I'm rading that you should paint every 2 years on some site, some say 5-6. Zinc say once or twice a year, some say every couple years. Why are the Mexicans doing this every month or do they not know any better. Or are they taking my zinc off and putting it on someones elses and so on.They say the bottom needs repainting. I haven't been down yet to look but when does a guy know. We'll be down there in the next week or so to do a thorough lookover. Probably have her hauled out. Going to do the bottom I suppose. What are the signs that we should be seeing for needing paint, zinc changes.

[senormechanico]

Haul it. If you just purchased it, I'll bet it needs all of the above.
Mexico has several good boat yards.

One thing for sure:
Welcome to The Cruiser's Forum. This is a good place for decent advice.
You won't get any bruises from people touching you with ten foot poles!

[onestepcsy37]

depends. i'm almost never in a marina and i use the best hard bottom paint made. my zinc lasts maybe a year and my bottom paint four years or more.

if you are in a marina with a lot of electrical activity in the water your zinc may dissolve quickly. but then all the other boats in the marina should have similar problems so you might want to check with other owners.

paint depends on the kind of paint (hard or soft), the quality of the paint, and the local conditions. if you're using 'soft' paint and the divers are scrubbing with sandpaper you'll be painting ever year. best to check with other boat owners in the marina to see what their experiences have been.

[fstbttms]

Originally Posted by onestepcsy37

if you're using 'soft' paint and the divers are scrubbing with sandpaper you'll be painting ever year.

In what world does anybody clean hulls with sandpaper?

[fstbttms]

Originally Posted by dnimigon

I know there has lots on here about when to repaint and when to change the zinc annodes. I've searched things out on differnet site and still don't have a clear answer. Our boat is in Puerto Vallarta. We just bought it. A Mexican has been cleaning the bottom every month and the zinc changed on the prop shaft. It's a 30 ft. Catalina. I'm rading that you should paint every 2 years on some site, some say 5-6. Zinc say once or twice a year, some say every couple years. Why are the Mexicans doing this every month or do they not know any better. Or are they taking my zinc off and putting it on someones elses and so on.They say the bottom needs repainting. I haven't been down yet to look but when does a guy know. We'll be down there in the next week or so to do a thorough lookover. Probably have her hauled out. Going to do the bottom I suppose. What are the signs that we should be seeing for needing paint, zinc changes.

Most quality, copper-based anti fouling paints, properly applied and maintained will last 2 or 3 years before they have spent their toxins and need reapplication. 5 or 6 years is very unlikely, considering that these paints are not designed to last that long. Unless you are cleaning the boat bottom yourself, the most telltale symptom of needing new paint for you is likely to be how quickly the hull becomes foul. But since you are an absentee owner, you probably have no way to judge this. If you know the paint is over 2 years old, my advice is to go ahead and repaint. Your hull cleaners are probably right.

Regarding zinc usage, there are many variables that affect zinc life. But if your zincs are truly being replaced on a monthly basis, that is very rapid depletion and indicative of a problem that needs resolving. Typically, you should be getting 6-9 months out your zincs. If there is an electrical problem affecting your zincs, the source is most likely going to be found aboard your own boat. Less likely to be a neighboring boat or the shorepower system.

Your main problem seems to be that you live nowhere near your boat and don't have confidence in the people maintaining it for you.

[onestepcsy37]

fstbottoms - i should have put quotation marks around 'sandpaper'. i meant scrubbing too hard, not actually using sandpaper!

i'm in florida / bahamas. my zinc really does seem to last a year. and pettit trinidad 75 really does keep my bottom clean four years. the prop is the bad guy. will foul in a month. until my diver put me on to sex wax. now it doesn't foul unless i motor a whole lot and the stuff rubs off. but at two bucks a cake and a fifteen minute free dive i think i can live with it...

[fstbttms]

Originally Posted by onestepcsy37

and pettit trinidad 75 really does keep my bottom clean four years.

What does that mean? That you don't have to have hull cleaned for 4 years? Or does it mean you feel you don't need to repaint for 4 years?

[onestepcsy37]

fstbottoms - i'm repainting right now after four years. i do my own hull cleaning and i find that almost all growth is around the waterline. down at the bottom (full keel, five foot draft) there's no growth.

a while back i was involved in a bottom cleaning thread here and was astounded at how often you guys on the left coast clean their bottoms. i don't know anyone here using a quality paint who has to clean that often.

[fstbttms]

Originally Posted by onestepcsy37

fstbottoms - i'm repainting right now after four years. i do my own hull cleaning and i find that almost all growth is around the waterline. down at the bottom (full keel, five foot draft) there's no growth.

Then your boat lives in a very low-fouling region.

[SVNeko]

I don't know, man, that sounds a little racist. I had my boat in PVR for a year and they did a great job keeping it clean and the zincs renewed. Never changed them too early. Maybe you're in a hot marina and have small shaft zincs. They worked with me to figure out the right schedule. I suggest you speak to them about it.

[fstbttms]

Originally Posted by SVNeko

Maybe you're in a hot marina and have small shaft zincs.

There are no "large" or "small" shaft zincs for a given shaft diameter. The OP has a Catalina 30, which has a 1" prop shaft. Regardless of whomever is manufacturing the zincs that are being used, they will be very similar in size, weight and and surface area.

That being said, it is my opinion that some zincs are of poorer quality than others. And you are correct, the OP needs to have a discussion with whomever is providing his underwater services.

[DumnMad]

There are dishonest people everywhere. Nothing racist about being wary of an odd maintenance regime.

[Tbrad]

Racist??? OMG such a trite tired worn out term that has come to mean little or nothing,

[SVNeko]

Look, I hate the PC police as much as the next guy, but the original post pretty clearly seemed to assume the worst about Mexicans generally. You don't see it that way, that's your prerogative. I've been ripped off a lot worse by boat service people in the US than Mexico.

[DumnMad]

There was a saying; the Pot calling the Kettle black.
So often in my experience the accuser is the real racist. Most cruisers are not wealthy and should be allowed to be defend themselves from being ripped off regardless of the country they are in.