Association Forum - keel zincs

Assn Members Area · Join

Home.

Association Forum

Ships Store

Cruising

Racing

Technical Tips

Photo Gallery - New

Boat Search - Updated

Manuals & Brochures

Swap Meet

Links

Officer Flag Line & Staff

Bylaws & Constitution

Members Area

Join the Association

Notice:
The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.

Association Forum

Username:	Password:
Save Password
Forgot your Password?

All Forums

Catalina/Capri 25/250 Sailor's Forums

Catalina 25 Specific Forum

keel zincs

New Topic

Topic Locked

Printer Friendly

Author

Topic

gerdo
Navigator

Member Avatar

107 Posts

Initially Posted - 04/09/2002 : 13:02:49

Will be keeping C25 swing keel in chesapeake bay this season, plan launch 4/30 and will keep in until mid december. There are no keel zincs on it. Should I put some on?

Edited by - on

dlucier
Master Marine Consultant

Members Avatar

Virgin Islands (United Kingdom)
7583 Posts

Response Posted - 04/09/2002 : 14:16:04

Gerdo,

Catalina Direct states on page 4.60 of the Catalina 25 handbook that,

"Keel zincs are mandatory in saltwater, recommended in freshwater to protect this entire assembly from electrolysis. Replace the zincs yearly. Zinc, a less noble metal, corrodes first and protects the iron, stainless steel, and bronze from corrosion."

That statement and the fact that the keel zincs only cost $11.50, I would say do it.

Don Lucier, Northstar
C25 SR/FK

Edited by - on

gerdo
Navigator

Members Avatar

107 Posts

Response Posted - 04/09/2002 : 16:04:15

thanks for the reply Don. I assume I would drill the keel and through bolt the zincs.

Edited by - on

dlucier
Master Marine Consultant

Members Avatar

Virgin Islands (United Kingdom)
7583 Posts

Response Posted - 04/09/2002 : 16:31:58

Gerdo,

I assume so, but I don't know for sure since I have a fixed keel boat. Is there anybody out there with any advice?

Don Lucier, Northstar
C25 SR/FK

Edited by - on

Bruce Baker
Captain

Members Avatar

USA
402 Posts

Response Posted - 04/09/2002 : 20:12:41

Gerdo,

I've just bought a swing keel boat myself, and noticed while painting the keel a disc about 4 inches in diameter on the starboard side, close to the pin. My guess is that this is where the zinc goes. FYI, I'll be keeping my boat in the Potomac after sailing it to Alexandria VA from Rock Hall, MD where it sits currently.

Edited by - on

Ed Montague
Captain

Members Avatar

USA
499 Posts

Response Posted - 04/09/2002 : 23:06:45

My swing keel has a tear drop shaped zinc on each side of the keel about half way up. They are attached with machine screws into a threaded holes in the keel. Drilling all the way through the keel will be a chore. Just drill a hole about 1" into the keel and tap it. Be careful with the tap, cut partial turns and back it out and then cut some more and back it out, etc. Be sure to use cutting oil. Salt water boats need zinc and fresh water boats should use magnesium, fresh water is less conductive and magnesium is less noble. Having said that, my boat is in fresh water most of the time but I have Zinc anodes because I didn't know better and it seems to work. Next time I replace them it will be with magnesium.

Ed Montague on 'Yahoo'
1978 #765 SK, Stnd, Dinette ~_/)~

Edited by - on

gerdo
Navigator

Members Avatar

107 Posts

Response Posted - 04/10/2002 : 09:09:41

Now this may be a stupid question, but what material should the bolts be. Stainless, or zinc coated?

Edited by - on

Buzz Maring
Master Marine Consultant

Members Avatar

USA
1768 Posts

Response Posted - 04/10/2002 : 09:59:17

<BLOCKQUOTE id=quote>quote:<hr height=1 noshade id=quote>
Salt water boats need zinc and fresh water boats should use magnesium, fresh water is less conductive and magnesium is less noble.
<hr height=1 noshade id=quote></BLOCKQUOTE id=quote>

Hi Ed,

I'm dusting off a lot of brain cobwebs, but it seems to me that I learned from chemistry courses that magnesium explodes <img src=icon_smile_shock.gif border=0 align=middle> when it comes in contact with water ... did I dream that? (I never much liked chemistry anyway.)

Buzz Maring, C-25 SK/SR #68, "Freya"

Edited by - on

Ed Montague
Captain

Members Avatar

USA
499 Posts

Response Posted - 04/10/2002 : 12:58:22

Gerdo, The screws that hold the anodes on are Stainless.
Buzz, Check page 473 in the 2002 West Marine catalog. Gives a good discription. However, you may have uncovered an evil plot to sink all C25 swingers.<img src=icon_smile_wink.gif border=0 align=middle>

Ed Montague on 'Yahoo'
1978 #765 SK, Stnd, Dinette ~_/)~

Edited by - on

f_sondergaard
1st Mate

Members Avatar

USA
92 Posts

Response Posted - 04/12/2002 : 12:34:21

For our 25 swing keel, we just drop over a zinc fish with a cable that we attach to our keel drum. about every eight months we replace the zinc fish. West Marine has this set up. We use this only at the dock! This works great for us, no holes to drill!!

Edited by - on

Ken Cave
Navigator

Members Avatar

USA
148 Posts

Response Posted - 04/14/2002 : 23:48:36

OK Folks: You can mess up your swing keel by putting zincs on it-and getting extensive damage to your trunk when you try to raise your swing keel-or not!!

I had my boat in the SALT water for a number of years without zincs and had no problems with the boat or any of its thru hulls.

Now, lets think this out!! What do you have in tha water that can possible eat away? A swing keel! What is it attached to it to conduct electricity? Nothing!!

Your engine? Yup, you have a problem there-but if you look at it, it has a zinc on it somewhere to protect it. And, if you are smart, you will raise your outboard out of the water when you are through sailing it.

You will do more damage in using an automotive battery charger on the boat in the water. That is why you must use a charger made for marine use!!

Ken Cave

Edited by - on

Ken Cave
Navigator

Members Avatar

USA
148 Posts

Response Posted - 04/14/2002 : 23:53:22

Gerdo:

If you have a fixed keel, chances are that you have some system grounded to the bolts on the keel. If you do not have an inboard engine with a zinc on the prop shaft, better be safe than sorry. Put a zinc on your keel just for preventive maintanence.

Ken Cave

Edited by - on

MattL
Admiral

Members Avatar

USA
990 Posts

Response Posted - 04/15/2002 : 09:40:44

Buzz,
If Magnesium exploded in water, the recent plane crashes in to the various bodies of water would have been much more explosive. Mg, is a very light weigth and strong material. The problem is that it can catch fire. That's why plane creashes do not have lots of debris. Also why some automobile fires are extreamly hard to put out, Mg engins. It is also the metal used in the old flash cubes.
I think the metal you are thinking of is sodium, over one spot on the periodic table with 1 electron in the valence level, Mg has 2, it is very reactive and will react with moisture in the air. In water it is quite spectacular.
there is your science lesson for the day.

Matt
EC Rider
Cat 25 86'
FK SR

Edited by - on

Buzz Maring
Master Marine Consultant

Members Avatar

USA
1768 Posts

Response Posted - 04/15/2002 : 10:29:08

<BLOCKQUOTE id=quote>quote:<hr height=1 noshade id=quote>
Buzz,

... there is your science lesson for the day.

Matt
EC Rider
Cat 25 86'
FK SR
<hr height=1 noshade id=quote></BLOCKQUOTE id=quote>

And a good lesson at that ... thanks Matt, the cobwebs are starting to part ... a little.

Buzz Maring, C-25 SK/SR #68, "Freya"

Edited by - on

Topic

New Topic

Topic Locked

Printer Friendly

Jump To:

Association Forum

Notice: The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.