Do I need zincs on my trim tabs?

ksgoldman

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Next month I will be launching a new 2010 Grady White Tournament 275 that comes with factory installed Bennett trim tabs. Do I need zincs on the trim tabs? Should I have the trim tabs painted?

I had Bennett trim tabs installed on my last boat (a 2006 Seaswirl Striper 2010DC) and the dealer installed zincs on the tabs (they drilled through the plane of the tabs and installed round zincs). I was actually very concerned when the zincs were gone after two months of being in the water and called boatzincs.com and they recommended larger zincs than what my dealer had installed on the Striper. I installed the larger zincs and they made it through the rest of the season.

The issue is that if the first set of zincs disappeared after two months, obviously there was something that caused them to deteriorate. I keep the boat on a mooring in a saltwater river (actually a tidal strait). I had my last trim tabs painted but the paint wore off in a month.

Although there are some trim tab zincs that fit on the mounting screws, because of the way that Grady White mounts the trim tabs, that style of zinc doesn't work.

I'm curious what others do about zincs on their trim tabs.

Thanks,

Ken
 

Lainie J

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Zincs

I have never had zincs on my last tabs on my last 3 Grady's and never had any issues. My Marlin is a 1997 and the tabs are perfect.
 

Tommyboy

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1st of all, congrats on your new boat ! I would recommend Zinc's, sounds like you have some electrolosis issues at your marina. I would talk to the dealer , this is a brand new boat! they should handle this for you ....
 

SmokyMtnGrady

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What are the made out of? Aluminum or ss? It seems aluminum would take a lot of time to corrode. It might get pitted, but it is not like you are boating in the dead sea. Zinc is used as a sacrafiscial annode where galvanic corrision would an issue in areas where dissimilar metals come into contact with one another and sea wster? I don't see the need for zinc on the tabs since they are usually 1 type of metal connected to the actuators with a nylon bushing. However, I could be wrong here.
 

Pete1313

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If you are keeping your boat in the water, no question - zinc the tabs.

Here is my new to me Voyager that sat in the brine and did not have zinc on the tabs:

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I'll be replacing these very soon.....

In my mind, no reason not to put zinc on them. I see tons of boats in my neck of the woods with the flat round zincs on their tabs.
 

seasick

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At my club, everybody with tabs uses zincs. They usually last only one season so something is going on and I would rather replace zincs than tabs, brackets or screws. These boats are in salt water and stay in all season
 

catch22

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If you have, or add zincs... what about grounding, (bonding) the tabs?

I would think it would be necessary for the zincs, (anodes) to work properly... yes/no?
 

wahoo33417

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I guess I have not paid much attention, but I don't recall seeing zincs on Grady tabs. I'm not sure where they would go? Couldn't go on top of tab because tab retracts into a pocket. If on bottom of tab, wouldn't it create some drag?

Also, not sure how far this will go in Ken's situation, but Grady's version of Bennetts come painted to resist corrosion.

If it were me, I'd call both Grady and Bennett before drilling holes.

Rob
 

sluggoe

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agree......not sure where you would put the zincs on the tabs and would create drag if placed on the bottom;

i guess i f the zincs were small enough that that they did not encroach when in the full up position then maybe would work;

i have never seen zincs on bennett tabs on any grady white;

would probably replace the tabs instead of drilling holes....

-slugg
 

uncljohn

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my tabs are painted w/ primer and antifouling paint. Had my boat in the water for the past 8 years and never had a zinc on the tabs, or corrosion.
 

catch22

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Camp does have zincs specifically for Bennett tabs - http://www.boatzincs.com/bennett-trim-t ... e-kit.html
I've never used these, and I wonder if the mounting screws would become lose, after the zincs start to wear. They use the same screws, (only longer) that attach the plane to the plastic hinge on the actuator. Also, since the hinge is plastic, you can only tighten them so much, (to avoid stripping). Might be worth using an even longer screw and a lock nut, (if there's room).

With the rudder type zincs, you can mount just the half on top of each plane, so there's no additional drag on the bottom, (except for the bolt head). One half will be threaded, so all you need is a bolt. You'll need to use a bolt and lock nut on the other half.
 

seasick

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catch22 said:
Camp does have zincs specifically for Bennett tabs - http://www.boatzincs.com/bennett-trim-t ... e-kit.html
I've never used these, and I wonder if the mounting screws would become lose, after the zincs start to wear. They use the same screws, (only longer) that attach the plane to the plastic hinge on the actuator. Also, since the hinge is plastic, you can only tighten them so much, (to avoid stripping). Might be worth using an even longer screw and a lock nut, (if there's room).

With the rudder type zincs, you can mount just the half on top of each plane, so there's no additional drag on the bottom, (except for the bolt head). One half will be threaded, so all you need is a bolt. You'll need to use a bolt and lock nut on the other half.

Those zincs look very interesting...
 

3rd Day

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PETE 1313, That looks some salty water right there. Most of the larger boats around here that live in the water have the round zincs on the tabs. I'm not sure of the life expectancy, but 2 months seems kinda short. Just mho.
 

catch22

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seasick said:
catch22 said:
Camp does have zincs specifically for Bennett tabs - http://www.boatzincs.com/bennett-trim-t ... e-kit.html
I've never used these, and I wonder if the mounting screws would become lose, after the zincs start to wear. They use the same screws, (only longer) that attach the plane to the plastic hinge on the actuator. Also, since the hinge is plastic, you can only tighten them so much, (to avoid stripping). Might be worth using an even longer screw and a lock nut, (if there's room).

With the rudder type zincs, you can mount just the half on top of each plane, so there's no additional drag on the bottom, (except for the bolt head). One half will be threaded, so all you need is a bolt. You'll need to use a bolt and lock nut on the other half.

Those zincs look very interesting...

I just spoke with someone about those. I don't want to say who or where... but, they confirmed my fears. They recommended using the rudder type zincs.
 

whaler248

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Trim Tabs

I have had my trim tabs painted with antifouling paint everytime I paint the bottom (every season with ablative paint), and have had no issues. The tabs operate fine and the growth is held to a minimum.
 

richie rich

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The anodes only work if they are completely exposed (not painted whatsoever) and the metal they are secured to is bare as well....they are designed to give up before your metal, SS or aluminum...do not bond or ground them...just install a small donut shape or flat bar shape onto clean metal, on top of your trim tabs and let them do there work...its a simple , cheap and easy install...your DC system is a floating system as does not require grounding to a metal source like a thru hull intake or trim tab.