Adding Zincs to Bennet Trim Tabs

[Luna Sea]

Hi, thanks for looking in,<br /><br />I want to add zincs to my Bennet Trim Tabs. They measure 12" x 18" x .078 thick (5/64"). I was at the marine store yesterday looking at the small round rudder type zincs, looks like my options are 1 7/8" dia x 1/4 thick or 2 13/16" x 1/2" thick. The smallest size appears to not have much too it, so I bought the 2 13/16" x 1/2". It does look like the screws holding the tabs in place need some protection, that's why I'm doing this. I guess I'm gonna drill some holes in the center of the tabs tonight and add these. Unless someone says use the tiny ones, or maybe one zinc for two tabs? Just put a disc on the topside of the tabs? Any drag created having something under the tabs? Thanks for the free advice.....

 

[AntsGrady]

Re: Adding Zincs to Bennet Trim Tabs

Ya, just drill a hole in the middle and clamp the zinc on....1 half on top and the other the bottom. Make sure there is no antifouling painting where the zinc is mounted. Get some blue lock tight and tighten the screw. You'll be good to go. I just did the same thing and there is no drag etc.....

 

[mattttt25]

Re: Adding Zincs to Bennet Trim Tabs

pls let me know how it goes. i'm still undecided on painting or zincing my tabs. a guy at the grady dealership said they never paint or install zincs to tabs, even on the larger grady's they paint and prep for their customers. just don't know what i should do.

 

[Luna Sea]

Re: Adding Zincs to Bennet Trim Tabs

I'll be drilling tonight then. Couple of the screw heads holding them on didn't look so hot, structurally they're probably fine but I want some zincs on there to make sure thay stay that way........<br /><br />Just forked out 5 bills for a prop as the other one was all pitted up, so zincing up to the max this year.<br /><br />Yard that launched me last year, per instructions from previous owner, supposedly zinced the boat, but there was no sign of a shaft zinc when I hauled, and I'm wondering if they just did the rudder one, if even. I'll be diving mid season to check them this year. Shouldn't have electrolysis problems on a mooring, but one never knows.......<br /><br />Think of it as cheap insurance...

 

[Stratocaster]

Re: Adding Zincs to Bennet Trim Tabs

I put 4" pancake zincs on mine in the fall and they always barely make it to the next fall. I would think smaller ones would burn up quicker. Not a big deal for trailer boats but definitely a big deal if you have to haul to change them.

 

[AntsGrady]

Re: Adding Zincs to Bennet Trim Tabs

Do you guys just wire brush the zincs every year to clean them? Thats what I've been told to do or they are basically useless.

 

[navigator336]

Re: Adding Zincs to Bennet Trim Tabs

If you're in salt water you need the zincs. Half on the top and half on the bottom. The turbulence is minimal. I'd put the larger ones on. If your shaft zincs were missing, you may be in a "hot" area. On a mooring, unless there's boats very close, its unlikely that a leak on a neighbor is causing the fast electrolysis. My shaft, hull and tab zincs used to go very fast until I put a galvanic isolator into the main ground. I'm reasonably sure the boat in the slip next to mine is "hot". The isolator did a great job.

 

[umblecumbuz]

Re: Adding Zincs to Bennet Trim Tabs

Any extra turbulence is to much. You don't want anything sticking out under the tabs if you can avoid it. Why do it?<br /><br />Just put the zincs on the top of the tabs. They're not protecting the tabs so much as stopping the tabs accelerating corrosion in 'lesser' metals elsewhere on the boat.<br /><br />Zincs should be kept free of oxides - furry or whitish deposits. AntsGrady's method is good insurance. If the deposits are too hard, file them off. Replace the zincs when they're half gone, because it's the surface area of the zinc that affects its efficiency.

 

[cuzner]

Re: Adding Zincs to Bennet Trim Tabs

Depends on the condition of them. My boats a 94 and still has the origonal zincs on the tabs, the rest get replaced as needed. If your in salt water if there are showing any rot I,d replace them before I put it in for season. Shop around for a decent price... them little buggers can be expensive if you replace them every year.<br /><br /> Jim

 

[Stratocaster]

Re: Adding Zincs to Bennet Trim Tabs

Expensive? My 4" zincs were $14.00 CDN. Compared to the cost of under-zincing, that sounds pretty cheap to me!

 

[cuzner]

Re: Adding Zincs to Bennet Trim Tabs

Hey Mike... I was feeling bad for my marine mech. when I Brought my boat in for a pre season check-up. Did'nt need anything done, and I was planning on doing zincs myself. I told him to go ahead and change the zincs, only the 4 on leg needed replacing( tab zincs still like new). 105$ ..70$ for zincs, the rest labour and tax.<br /><br /> Jim

 

[umblecumbuz]

Re: Adding Zincs to Bennet Trim Tabs

Zincs in direct contact with stainless will usually last a lot longer than zincs fitted to 'lesser' metals elsewhere on the transom.<br /><br />If the 'lesser' metals don't have active zincs (neglected zincs can become inactive) then the zincs fitted to stainless parts - like tabs - will erode faster.

 

[Boatist]

Re: Adding Zincs to Bennet Trim Tabs

I fish Saltwater but do trailer my boat. Had Bennett Tabs on since 1981 and no Zincs except the one that came on my outdrive back in 1980. It is still perfect.