Zincs

[oscarvan]

After experiencing some speed loss for a given power setting I had a diver check out the subaquatic portion of Lady Kay. He reported the paint in good shape (it was done a year ago) but the metal dirty. Enough to where, in his opinion, it would cause the noted degradation of performance. Some boats are more sensitive than others. Is it the opinion of this body that these boats are in fact quite sensitive to contamination on the wheels?

He also reported the zincs in good condition. I have never seen my boat out of the water and the pictures are inconclusive as to the zinc configuration. It looks like two discs on the top of each rudder, and clamshells on the prop shafts, one each side between the aft and middle struts. A total of 4 locations. Are there supposed to be any more?

In retirement I mow my own lawn, and I guess I'll have to clean my props regularly too. (I have the gear). Saves me money I can dump in other areas of the boat.

 

[Photolomy]

That is what my boat has. Two on each rudder (opposite each other) and two on each shaft (either side of coupling). When I had a degradation, it was growth on the prop.

 

[oscarvan]

Ah, TWO on each shaft. Total of 6 thanks. Those are easy to find underwater.

 

[Briankinley2004]

I clean my own as well and mow my own lawn. I am getting tired of both. Here in FL it seems like both are year round jobs.

 

[Captain Ralph]

Some marinas do not allow DIY bottom dives. Please mind your marinas rules when it comes to diving your own boat.
Be safe down there.

 

[oscarvan]

Some marinas do not allow DIY bottom dives. Please mind your marinas rules when it comes to diving your own boat.
Be safe down there.

Our marina is pretty chill, don't recall reading that in the rules but I'll check. However plan is to find a nice anchorage with some current. Never liked sitting in that muck cloud. Used to do this on previous boats.

 

[rwaldrop13]

We're here in Fort Myers, and I was lucky enough to get acquainted with a local dive company that used to work with the Navy in the Pacific. They do a good job for me, but shared some interesting information. A local repair vendor that I know and trust also backed them up on this. I have the flat plate zincs on my rudders and trim tabs, but only one zinc ball on each shaft. They said if you're in a marina, too many zincs can actually increase the galvanic action under your boat rather than protect from it. I reached out to a couple of engineer friends from my Coast Guard days, that now own boats of their own and they agreed with this, saying better to double the shaft zincs once you start cruising, but with 6 zincs total I am actually in good shape for now.

 

[Briankinley2004]

Some marinas do not allow DIY bottom dives. Please mind your marinas rules when it comes to diving your own boat.
Be safe down there.

I don't have that issue to deal with but when I had it in a marina they never said anything about me diving my own boat. Thats getting pretty communist to me, telling someone they can't inspect their own property. Im glad I never had to stay in a marina like that.

 

[Captain Ralph]

I don't have that issue to deal with but when I had it in a marina they never said anything about me diving my own boat. Thats getting pretty communist to me, telling someone they can't inspect their own property. Im glad I never had to stay in a marina like that.

Agreed
The stuck up Marinas and wanna be stuck up marinas in Jax have these rules.
They want the diver companies with $2m insurance to go under your boats and their docks.
And, the dive companies wave liable from the marina when under there (leaking) docks when they sign in.

 

[Captain Ralph]

I always believed over zink was O K.
Better to give up monkey metal than your expensive bronze.
If they burn up quickly, zinc up well and find your (others) voltage leaks.

Having lived in some better marinas and working marinas, I'll tell you, there are some boats to stay away from and no amount of zink will protect you.
Just throw a volt meter lead in the water and accidentally trip a suspect boats shore breaker, (when nobody is on the suspect boat is preferred).

I remember there is a formula for figuring zinks per metal protected.
I can not find it.

 

[oscarvan]

Just throw a volt meter lead in the water

More specific? Where does the other one go?

 

[MadHatter53]

I use two on each shaft, one 5” on each rudder and I have a transom divers plate as well. I land store my boat during winter and usually the rudder zincs are 50% worn, the transom maybe 30% but my four shaft zincs are barely touched and everything gets replaced in the spring.

 

[Captain Ralph]

More specific? Where does the other one go?

On your internal bonding system; thru hull fitting, shaft or interconnecting straps.

Then in a separate test, the green ACv fault current wire.

 

[JuiceClark]

I wrote a funny little 30 page thing about building a barnacle barrier. If you have half an hour, I think you'll find it pretty funny. I actually had an old Trojan F36 that made it 7 years without a bottom job and no barnacles...used to enjoy messing around with ideas.

BUT, the PDF is 3 megs and the site will only let me upload half a meg. If there's another way to post a bigger file, please let me know. It won't let me upload a ZIP file, either.

 

[rwaldrop13]

I always believed over zink was O K.
Better to give up monkey metal than your expensive bronze.
If they burn up quickly, zinc up well and find your (others) voltage leaks.

Having lived in some better marinas and working marinas, I'll tell you, there are some boats to stay away from and no amount of zink will protect you.
Just throw a volt meter lead in the water and accidentally trip a suspect boats shore breaker, (when nobody is on the suspect boat is preferred).

I remember there is a formula for figuring zinks per metal protected.
I can not find it.

Thanks Ralph. One of these days if you're in Fort Myers, I'll buy the first beer!

 

[Captain Ralph]

Thanks Ralph. One of these days if you're in Fort Myers, I'll buy the first beer!

Outstanding Plan.