keel fin

Corrosion, Paint, Through Hulls, etc.
Butchel
Tin star
Posts: 22
Joined: Sat Nov 19, 2016 11:29 am

Re: keel fin

Postby Butchel » Tue Jan 17, 2017 7:59 pm

I think the "boatyard guy" who, by the way has fully restored a Marinette before and reads this forum, really likes to weld. But, the yard is so busy that he hasn't gotten around to re-welding the keel fin. The old boat needs so much work that it is almost overwhelming. I'm one week into a planned six week work session and everyday I find something that is broken, rotten or missing entirely. I feel like I'm backing up. If a man went into this with his eyes wide open, he wouldn't go. I've been sick for three days with the swamp flu and the Cowboys lost to the Packers! What else can go wrong?
What is a mag. anode? Is it magnesium? If it works in fresh water, why wouldn't it work in salt water? Thanks for all your input. I'm listening.
.

honestcharlie56
Royal Aluminum Star
Posts: 232
Joined: Tue Jul 19, 2016 8:27 pm
Location: Lake Charles, LA

Re: keel fin

Postby honestcharlie56 » Wed Jan 18, 2017 12:43 am

Need zincs in salt
1990 Marinette 32 Sedan Flybridge "Hubba" Lake Charles, LA
Twin Chrysler 318's

jralbert
Site Admin
Posts: 550
Joined: Fri Jul 11, 2014 9:15 pm

Re: keel fin

Postby jralbert » Wed Jan 18, 2017 12:53 am

Butchel wrote:What is a mag. anode? Is it magnesium? If it works in fresh water, why wouldn't it work in salt water? Thanks for all your input. I'm listening. .
I'm not up for the scientific explanation at this hour but wanted to comment on your question. Salt water is a better conductor of electricity than fresh and the ions really speed up metal loss under salt conditions. Aluminum based vs mag based anodes are better suited to do the job in each situation because of their inherent qualities. I don't think it's a a question whether mag anodes work...it's a matter of which one works best in each situation. Your boat hull and fittings could depend on your making the right choice for your waters
-joel-
former owner 1988 '32 FB Sedan
Chesapeake Bay
twin 318 / 240 hp
Potomac MD

barkleydave
Site Admin
Posts: 353
Joined: Sat Jul 12, 2014 6:18 am
Location: Kentucky

Re: keel fin

Postby barkleydave » Wed Jan 18, 2017 8:10 pm

I believe we have provided the information you have requested to make an informed decision.

safe harbors,

dave
1987 Marinette 29 FB Sedan
Retired Boat Accident UL and USCG trained investigator
Retired USCG Captain

javalin390
Royal Aluminum Star
Posts: 265
Joined: Sat Jan 10, 2015 7:14 pm
Contact:

Re: keel fin

Postby javalin390 » Wed Jan 18, 2017 8:53 pm

The following information I downloaded & printed before John Althouse suffered his stroke, when the M web site was still running. Use of the correct anode is crucial, and Marinette specified anodes developed for our boats, that being KA90 or "SEALLOY". These are what Marinette used from the factory. I can tell you, on mine that I can get a couple years out of them, removing & cleaning the mounting surfaces each year and my Capac meter reads 0.9mv as it should. Mag IS NOT recommended, but if used, ONLY in fresh water, and note that it will deteriorate much faster than Sealloy/KA90. The information also states that zinc should not be used, because it is so close, on the galvanic scale to the Al hull, that it would provide very little protection.
Jim Elias
1974 37' SedanFlybridge
Twin 360 Chryslers.
Marblehead, Ohio

User avatar
carl
Royal Aluminum Star
Posts: 342
Joined: Sun Feb 08, 2015 5:58 pm

Re: keel fin

Postby carl » Thu Jan 19, 2017 1:59 pm

I just visited boatzincs.com as mentioned by Dave in his post and learned a couple of things. First I realized owning a 32' Marinette will only require me purchasing three 36" lengths of anode strip. Secondly it appears I will have to drill the anodes myself, this is not a problem for me just looking to confirm that's what you guys regularly do, these anode strips from boatzincs.com do not come predrilled for the Marinette is that correct? And lastly I learned of the hanging anode which I think is a nice little slice of insurance and I will be ordering one promptly, my question is where do you guys attach the large alligator clip to on your Marinette? I would think I would want the best contact point on board.
1990 Marinette 32' Sedan Fly Bridge
Twin Crusader 350's
Chickamauga Lake, Tennessee

User avatar
bcassedy
Royal Aluminum Star
Posts: 323
Joined: Sun Jul 13, 2014 10:05 am
Location: Aurora, In.
Contact:

Re: keel fin

Postby bcassedy » Thu Jan 19, 2017 5:09 pm

Carl,
Correct, you will need to drill the anodes that you get from BoatZincs. If your existing keel (and trim tabs & rudders) don't have holes drilled in them yet, you'll need to that as well. The good thing, after you've done this the first time to the mounting surfaces, you've got a template to use for the next set of anodes when this set needs to be replaced.

I used the following method:
1. Cut all the anodes to proper lengths
2. (first time mounting)... use "C" clamps to position and hold the anodes in place. (ie. on the keel, you'll have anode / keel / anode clamped in place.
3. For the keel I used 6 SS hex head bolts + corresponding flat washers and locking nuts (they have plastic inserts that will keep the bolt in place - no lock washers needed). This ensures a good metal to metal contact.
-> Use the same combo for mounting trim tab and rudder anodes.
-> This makes it very easy to disassemble and reassemble. I do clean up the bolts's threads just to be thorough.
4. Drill 6 holes thru the clamped anode/keel/anode combo. Use a scratch awl to mark the forward position of each of the anodes into the keel.
5. Using a good scratch awl (or the tang end of a file), etch each anode as Port or Starboard with an arrow pointing to the bow. Why? The anodes might last a couple of seasons or so. You'll want to pull them off the keel/rudder & trim tabs to clean them up as well as the mounting surface. On the keel set, it's nice to have the etching in place to help with "where does this go and which way?" (being older and layin' on my back, I like to get that part of the "fun" of owning a boat over with quickly! :-] ). The trim tabs and keel are etched with just Port or Strbd. I use 2 bolts on the rudders and 4 on the trim tabs (trim tab mounting is on the outside vertical edge (makes it easier for mounting / dismounting)).
6. When it comes time to replace the anodes (keel), I just need to "C" clamp one anode at a time, positioning the forward edge adjacent to the mark made in #4 above. Drill the anode using the holes in the keel from #4. Dismount the anode, mark it as indicated in #5 above. Mount the other anode and repeat. Mount them and the keel's finished.
7. For the trim tabs and keel - you can use the old anodes as a template -OR- "C" clamp the new anodes in place, use a Sharpie to mark the mount holes, drill, mark Port/Strbd and mount.

As for the hanging anode - I believe Jeff once indicated he hung it from a railing. If you don't have one, you can get a cheap volt meter from Harbor Freight to check continuity. Just touch one lead to the SS wire and touch the other lead to any non-painted metal surface (such as the bolt head of a rail stanchion at deck level). Get a good reading? You're all set!

Bill
Bill & Sharon Cassedy
"Sunset Seeker"
'88 32' Sedan Bridge
Located in Aurora, In.
Twin 318cu in Chrysler
1.5:1 Velvet drive trannies
Fresh water only

User avatar
carl
Royal Aluminum Star
Posts: 342
Joined: Sun Feb 08, 2015 5:58 pm

Re: keel fin

Postby carl » Fri Jan 20, 2017 4:54 am

Hey thank you Bill for the detailed explanations and instructions, much appreciated. I know I already have anodes on my boat because I can see them on the rudders and the trim tabs, I have yet to see the two 36" strips along my keel because I have not pulled the boat yet but that day is coming, I'm fairly certain I have anodes on the keel as well, in what condition is yet to be determined. What I learned is that the anodes do not come predrilled for the Marinette, and I'm fine with that as I have the industrial arts skills to perform that task. I will certainly use stainless nylock nuts and stainless button head allen bolts with flat washers. All good advice well taken. Thanks again, this is what I love about a friendly, helpful and intelligent forum such as you guys have obviously been participating in for some time now, really glad I found it. The MOTTO should read "The Marinette Boat Forum, Where Sound Advice is Shared and Friendships Begin"
1990 Marinette 32' Sedan Fly Bridge
Twin Crusader 350's
Chickamauga Lake, Tennessee

User avatar
bcassedy
Royal Aluminum Star
Posts: 323
Joined: Sun Jul 13, 2014 10:05 am
Location: Aurora, In.
Contact:

Re: keel fin

Postby bcassedy » Fri Jan 20, 2017 7:45 am

I like you quote!!!

We're here to help each other.
(And for me it gives me a chance to live up to my kid's nickname for me... Overkill Bill. ;-) )

Bill
Bill & Sharon Cassedy
"Sunset Seeker"
'88 32' Sedan Bridge
Located in Aurora, In.
Twin 318cu in Chrysler
1.5:1 Velvet drive trannies
Fresh water only

martindesign
Aluminum Star
Posts: 104
Joined: Sun Mar 29, 2015 2:07 pm

Re: keel fin

Postby martindesign » Fri Feb 03, 2017 5:26 pm

Jim is spot on. Ka90 is best because of the type of aluminum that marinettes are built with.
Machanic, fabricator, carpenter, plumber, electrician, designer, hotrod builder and glutton for punishment. :ugeek: current boat; 1969 Marinette 32 express bridge 440's
Catawba Oh