Trim Tabs should be painted?

[davez]

I took my 2016 R31 to IMC (Lopez Island) last month for its 2nd annual maintenance, and they scraped four shovel fulls of barnacles, shells, etc off the trim tabs. They were sure the tabs were never painted, but said they should be. I wasn't prepared to leave the boat overnight for this painting (I'm on San Juan Island) so I didn't get the painting done.

I've seen discussions here on options for painting the trim tabs, but not the "official" Ranger position on this. Should they be painted as part of routine maintenance (and when new)?

Thanks

P.S. This is another reason to remember to dock your boat with trim tabs up ... IMC said that if enough build-up occurs on the trim tabs if left down, raising them could then damage something if those barnacles and shells are compressed.

 

[baz]

I don't know what RT's position/advice is on this aspect (the trim tab painting question). However, I see from several postings here that the tabs can be painted so long as the anodes are left completely exposed. Even the anodes can collect cauliflower like crud over time and that can be scrubbed off as required.

I will be asking my underwater diver service about the trim painting advice.

 

[Brian B]

I don't know what the "official" RT position is but if underwater metals are not painted you will get sea growth. I paint the trim tabs, underwater portion of the swim platform supports, rudder, prop and water intakes on the hull with Petit Barnacle Barrier. Do not paint the area where the trim tab zincs are attached. Check out Bennet trim tab website and they tell you how they are to be painted. I use the round zincs on the tabs and I made up similar 1/4 plywood discs, I attach them to the tabs, paint, remove the discs, and install the zincs on clean metal.

 

[Red Raven]

Agreed. Paint them if you keep the boat in the water.

I suspect RT leaves it up to the individual owner because the boats are trailerable and the need to paint the tabs/rudder/prop depends on the usage. For example, we pull our boat each fall and clean it up and store it for the winter. I was hoping painting the tabs would be unnecessary. The first year it was only in for under 5 months and the growth was manageable. A quick pressure wash cleaned them up. The second and third years the boat was in the water a bit longer and we started getting barnacles on the tabs and rudder mount last year. While the main body of a barnacle comes off with the pressure washer they leave a deposit that is very difficult to remove. After many applications of barnacle blaster I succeeded in getting them clean again but I didn't want to go through that process ever again so now they are painted. I used cold galvanizing paint on the rudder which as far as I can tell is pretty much the same thing as Barnacle Barrier but a lot less money. I used an Aquagard product called Alumi-Koat on the tabs because it claimed to be clear and I just wasn't ready to coat the shiny stainless steel with galvanizing paint. To keep the Alumi-Kota clear (and even then it is foggy yellowish) it has to be put on in a very thin layer so I doubt it will last long and wouldn't recommend it for a boat that is in the water full time. If it doesn't get me through 6 mos. then I'm going with cold galvanizing or barnacle barrier next year.
I have not painted the prop as it doesn't get any growth. Probably because we use the boat a lot and it cleans off with each use.

 

[Brian B]

I tried the cold galvanizing paint last year and will never use it again, for the few dollars I saved I spent a couple of hours scraping crud and barnacles that I never had before. My boat is in the water for 6 months and the Petit paint works a lot better for me.

 

[Red Raven]

Thanks Brian. Good to know. Sounds like I'll be using Barnacle Barrier next year then!

 

[Andrew Custis]

Hello. This is correct that on factory boats that we do not paint the trim tabs or rudder. We have used different paints and none really seemed to last. I'm with Brian that scraping or brushing them every once in awhile beats the hassle and extra cost of painting.

 

[baz]

...snip...

I will be asking my underwater diver service about the trim painting advice.

I asked my underwater diver service. They stated that one solution is to use Propspeed. Use of typical bottom paint should not be used as it will easily slough/peel off.

"Propspeed is a solution to a problem which has frustrated owners and captains for years. ... Propspeed is an environmentally safe product and does not contain copper, tin or any other toxic substances which may cause environmental pollution. Performance."

"Propspeed’s unique “foul release” formulation produces a surface that does not allow marine growth to permanently attach."

Yes, marine growth can attach after Propspeed has been applied but can be easily removed.

IMO, so long as the trim tabs are in good shape and don't have signs of being pitted/eroded then what Andrew recommends is the best advice.

Thanks Andrew. 🙂

 

[Automaticman865]

Hi,
I've had a pretty good run with painting the tabs. Here in the Salem area I'm in a place where I can get a lot of growth. I clean off the through hulls with the scotchbrite wheels along with the prop, tabs, and rudder. Only the prop is taken down to shiny metal. Then I use 2 coats of barrier coat. Then after that 2 coats of regular bottom paint. Then take off the old zincs, sand the area under them and install the new zincs. Plus the barrier coat is a different color than the bottom paint so you can see whats working or not working.

Stuart

Btw saw a ton of Tugs at the Winter Island yard all getting ready to hit the water.

 

[Levitation]

I use cold galvanizing from the hardware store. I have been happy with it.
You do need to scuff it up and spray on a fresh coat annually, thereby exposing fresh particles of zinc at the surface. 80 or 120 grit wet-or-dry works good and allows the spay to adhere.
I will point out that my boat is in the ocean 3 months each year - so your experience may be different.

 

[knotflying]

I'm with Denny O. I used to use the cold galvanized spray by Pettit and it worked great for me. I reverted to buying a quart of brush on since it is less expensive. I am not sure why Brian B had issues with his. We cruise in the same waters and I never had a collection of growth. I think the cold galvanized is better than regular bottom paint on the running gear because it is more durable. Just make sure that you do not paint your zincs or underneath them so that you keep continuity for galvanic protection.

 

[BB marine]

Painting underwater metal hardware does two things, reduces marine growth and protects the metal from corrosion. You should not paint antifouling directly to the metal. Antifouling paint doesn't adhere well to metal and it actually will increase corrosion. Preparation is key to coating metal. Sand it , solvent wash it, apply a good metal etching primer, two coats of a barrier coat and two coats of the antifouling paint you use on the hull bottom. After this application you should be able to get multiple seasons of just pressure washing. like Stuart said the barrier coat is different color when you see that it is time to recoat. I use Pettit products , 6456 under water metal kit includes etching primer and tie coat (barrier) then over coat with Vivid. I used this method in the past with good success. I just finished it on my Cutwater's Rudder, both thruster housings, trim tabs, swim platform support rails, stainless steel keel guard, and engine and air thru hulls. The marina I store my boat at is a Volvo dealer. Volvo recommended this method on IPS pods for corrosion protection.
Brian Brown
26 Cutwater
PORT-A-GEE

 

[rheimb1]

I bought my boat new and had the boat painted with antifouling and the trim tabs were NOT painted. I am however in fresh water most of the time and I get no growth what so ever on them, for what it's worth.

 

[tlkenyon]

Does anyone have first-hand experience with PropSpeed or Prop Armor?

TK

 

[baz]

FYI...

I recall that on my previous R-25 (Classic) that the bolts that held the trim tab hinges to the transom was the one thing to keep an eye on. I found one or two of the bolts were becoming very corroded. The trim tab hinges were also seeing some erosion which bothered me as well. Parts of the hinge were almost eaten through after some 5 years.

I ended up replacing two of the trim tab hinge bolts and bonding them to the boat's bonding system on the inside of the transom.

My R-25 (Classic) was kept in salt water all year round.

 

[stwendl]

I am wondering how the bolts get corroded if they and the trimtabs are not part of the bonding system

My understanding of corrosion is that it occurs mostly due to currents between dissimilar metals. A current can only occur if there are connections between metals and the metals have to be different composition. So unless the trimtabs and screws are different metals corrosion should not occur due to currents. Yes , some screws may be sub quality and if the screws were replaced with Home Depot type screws of questionable source this might be possible.

Th only other scenario where this can happen is when one has voltage gradient in the water and the metal dipped in the water provides a better path than the water. There will be a localized current through the metal possible eating away the metal. Bonding would then allow that current to be redirected to a sacrifical anode

 

[baz]

Yes, it's all very confusing trying to figure out why certain things rust/corrode. All I can say it happened on my R-25 (Classic). I will post some photos in my Album shortly and hopefully this will show what I was dealing with. I'll add a link for these photos later on today, and place the link here..... 🙂

P.S. Here's the link to my Trim Tabs photo album - http://www.tugnuts.com/gallery2.php?g2_itemId=48245

Note that the hinge is crimped rather than being a real 'bona fide' hinge mechanism. Thus, this may account for there being insufficient metal contact between the hinge plate on the transom and the actual trim tab that has the anode on it.

 

[Red Raven]

It could be Crevice corrosion. See link below

[https://en.m.wikipedia.org/wiki/Cr...rrosion-Reference-Professionals/dp/0071475443

Curt

 

[BB marine]

I didn't want to start a new topic about painting trim tabs so I found this one and wanted to add this experience. Painting trim tabs and having success with it lasting is sometimes an issue. Pressure washing tabs usually peals the paint off. Two years ago I painted the tabs. I used Pettit 6455/044 primer kit and vivid bottom paint. It requires 5 steps, clean and scuff trim tabs, apply a coat of 044 etching primer, once dried apply a thin coat of 6455 tie coat metal primer, let it dry and apply a second coat then apply Vivid. There is a chart on the can that gives proper drying times based on ambient temperature. If re-coating is not done at appropriate times a slight scuffing is needed for the paint to adhere and achieve proper bonding. I followed this and had great results. I have pressure washed the tabs after two seasons of use and the paint stayed with no pealing at all. Last winter I made drop fins and needed to paint them. I still had tie coat primer left over and vivid bottom paint but no 044 etching. I called Pettit Technical customer service and asked if I could scuff the Stainless and skip the etching. He said if it was scuffed with 80 grit and washed with Pettit solvent it would adhere. Here is the results:

Painted the drop fin without Etching Pettit 044 primer.


Results after a season of use and pressure washing the drop fins. All of the primer and bottom paint pealed off while pressure washing. The trim tab area that was treated with the Pettit etching 044, two seasons power washing. Clean and the paint stayed.


It is possible to paint the tabs with good success and get multiple seasons of use. Don't skip any steps! All other metal components that have been painted I used the Pettit 044 etching and have had no paint pealing two seasons. Thru hulls, the keel shoe, swim platform supports. The 6455/044 works great. just don't forget the 044!