Rudder Zinc Size?

[neildeb2]

What size zincs do you use on your Hatt rudders? I have a 58LRC, and the diver has been using 3" zincs on mine. Seems kind of small to me.

 

[SEVEN]

4” is what I use. 3” on the trim tabs.

 

[Captain Ralph]

How soon have they been burning up? Compared to others on the shafts, tabs and stern plate zincs?
Also, behind the props, they may get some wash wear. More silt in your water, the more wear. Goes back to question #1.
The curve/shape of the rudder may not allow a larger zinc to lay flat may be a reason you are not getting a 4".
Old bottom paint could keep a 4" from laying flat also.

Also, remember, these are rite in front of your wheels and offer a lot of protection for them. If they are burning up quickly, I would go larger for sure. Goes back to question #1.

Divers also believe in employment continuation. Prove zincs need to be replaced, they keep a job. Reduce 1 or 2 dives a year, less money in his pocket.
Are you reviewing removed zincs?

 

[neildeb2]

The rudder and shafts last 6 to 6 months, the others last about 10 months. The diver is trustworthy.

 

[neildeb2]

oops. 6 to 7 months. Thx for the good questions.

 

[MadHatter53]

I use the 5” on my rudders and by the end of my 6-7 month season, the transom plate and rudder zincs are very well worn but my shaft zincs are almost untouched.

 

[Captain Ralph]

oops. 6 to 7 months. Thx for the good questions.

6 -7 months? I guess your in a tight packed marina with lots of DIY boats around you.

When we left Ortega Landing and went to the Huckins dock, our zinc life went from 6 month (near gone) to over 18 months (lots left). Same zincs, same diver.

We knew what boats were the culprits that we left behind.

Amazing, all of those old Hucks, old Mathis/Trumpys, old Hatts at the Huckins dock did not have or cause any issues.

 

[Briankinley2004]

I have two R-4's on each rudder and one 2.5" zinc per shaft. I change them every 6 months because I don't like diving in cold water. New ones go on in may then I replace in November as I normally don't get back in until March. Pretty sure I could push this schedule longer as the rudder zincs are normally at 75% when I change them and shafts probably 60-70%. When I was at a marina it seemed they were pretty much shot at 6 months so I agree with Cap Ralph on the stray current. Now that I am behind the house I may see how much longer I can keep the ones I installed in November. Seems like the paint is lasting longer too.

 

[52CMY]

I'm in the habit of running two 2 1/2 zincs on each shaft, and just replace the oldest one each dive. I've never had the older one fall off but it's been close sometimes. I run the slightly fatter CMR-5s on the rudders, CMR-4s on tabs and 4 bar zincs on my TNT hyd transom lift. They seem to burn about perfectly matched. Is this habit wise or foolish, I don't know?

 

[neildeb2]

Hmm. So if the rudder and shaft zincs are the only ones going in 6 - 7 months, is it maybe my boat that has the problem?

 

[Captain Ralph]

Hmm. So if the rudder and shaft zincs are the only ones going in 6 - 7 months, is it maybe my boat that has the problem?

Is your boat surrounded by other boats or alone on a hook or ball?

 

[Captain Ralph]

The rudder and shafts last 6 to 6 months, the others last about 10 months.

Going back to this post;
How far do the other zincs wear? What other zincs? Larger plates or bars?