Do the Anodes have to be bolted to the hull or can they by glued?

Corrosion, Paint, Through Hulls, etc.
Red5
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Do the Anodes have to be bolted to the hull or can they by glued?

Postby Red5 » Wed May 16, 2018 10:04 am

Does the sacrificial metal have to be bolted onto the hull? Or can I attach using some sort of adhesive?

I've been getting some pitting near my props and I was going to epoxy some strips near that area. Do they only work if grounded to the hull? Or do they function just be being there? :geek:
37 Sedan Twin CAT 3208's "Under Way is the Only Way".

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shade2u2
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Re: Do the Anodes have to be bolted to the hull or can they by glued?

Postby shade2u2 » Wed May 16, 2018 10:20 am

I believe that they need to have good surface contact with the hull - or shaft or tabs or rudder...
John
1986 39 Sedan w/Crusader 454 & 1.92 drive.
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EWRice
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Re: Do the Anodes have to be bolted to the hull or can they by glued?

Postby EWRice » Wed May 16, 2018 11:29 am

Bolted, welded, or you could glue them only if you had a bonding wire connected from the anode to the hull/rudder/tab/etc. Bolting is easiest.
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Re: Do the Anodes have to be bolted to the hull or can they by glued?

Postby jralbert » Wed May 16, 2018 11:40 am

Using adhesive to attach anodes prevents the two metals from making contact which is the opposite of what you must achieve. Very bad (and useless) idea -sorry to disappoint. Assuming your keel anodes are properly attached, what's the condition of the anodes on your trim tabs and rudders? Is the shaft properly isolated?
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former owner 1988 '32 FB Sedan
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Red5
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Re: Do the Anodes have to be bolted to the hull or can they by glued?

Postby Red5 » Wed May 16, 2018 11:53 am

My anodes are getting eaten up and there was still some pitting. I do Not want to drill through the hull to mount additional stuff near the props so I guess I will just replace what I can where it was originally placed.
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shade2u2
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Re: Do the Anodes have to be bolted to the hull or can they by glued?

Postby shade2u2 » Wed May 16, 2018 12:39 pm

Most are like these. I have not seen a Marinette with anodes on the hull other than the Keel.
I added small disks as an experiment to monitor protection...
I should probably add one to the rudder.

TRIM TAB
RUDDER & SHAFT
KEEL
Attachments
ZzTrimTabPort.jpg
zRudderPropShaft.jpg
ZzKeel.jpg
John
1986 39 Sedan w/Crusader 454 & 1.92 drive.
1984 28 Express Hardtop FOR SALE
w/single 360 1.5:1 drive
Ohio and Muskingum Rivers (Marietta, OH)

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Busia
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Re: Do the Anodes have to be bolted to the hull or can they by glued?

Postby Busia » Wed May 16, 2018 12:43 pm

They are SACRAFICIAL anodes. They are meant to dissolve. Go to BoatZincs.com to find out what kind and how many you need. Or call them up, they are helpful. Buy your anodes here too, they have the best prices. Good luck with your boat--
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Re: Do the Anodes have to be bolted to the hull or can they by glued?

Postby jralbert » Wed May 16, 2018 1:05 pm

Red5 wrote:My anodes are getting eaten up and there was still some pitting. I do Not want to drill through the hull to mount additional stuff near the props so I guess I will just replace what I can where it was originally placed.
In the 20+ yrs I've been following Marinette forum posts, no one has suggested or reported attempting to mount anodes by attaching them to the hull. Way, way too much risk of failure (although other items such as CAPAC, depth sounders do get attached to the hull because they are sealed with a marine caulk and anodes are not).

As noted above, and with photos, the points are keel, trim tabs, rudders, shaft (but really not needed if shaft is isolated).

Do you have CAPAC - what does the meter show?

Is it possible to include photos? Or better describe area that's pitted? Someone may have some helpful suggestion for you
-joel-
former owner 1988 '32 FB Sedan
Chesapeake Bay
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Potomac MD

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tundrarules
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Re: Do the Anodes have to be bolted to the hull or can they by glued?

Postby tundrarules » Wed May 23, 2018 3:49 pm

Red5, you still out there? Sounds like you may have a little stray current around your boat somewhere. Looks like you are in freshwater and will need Mil-Spec A-24779(SH) aluminum alloy (also called KA90 or SEALLOY 150) http://www.boatzincs.com/marinette-bar.html . They also sell guppies/ hanging anodes. I hang one off the side of my boat for a little extra protection.
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