Association Forum - Sacrificial Anode

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

Sacrificial Anode - New Q (I think)

New Topic

Topic Locked

Printer Friendly

Author

Topic

sethp001
Mainsheet C-25 Tech Editor

Member Avatar

814 Posts

Initially Posted - 06/29/2013 : 20:29:37

Hey guys, I've searched the archives but can't find the answer to this question.

I purchased the sacrificial anode for a cast iron swing keel from Catalina Direct, as well as their drill bit. Today, I figured out the proper technique for drilling the cast iron, and got the hole made.

The hole is near the trailing edge of the bottom of the keel. When I go to mount the anode, the two sides look like they will not make good contact with the keel because the keel is tapered.

How have any of you overcome this issue? Tapping the holes and screwing the sides of the anodes on separately instead of using the provided through-bolt?

Seth
"Outlier" 1987 Catalina 25 SR/SK/Traditional Interior #5541
"Zoo" 1977 Morgan Out Island 30
"Nomad" 1980 Prindle 16
"Lost" 1988 Catalina Capri 14.2 (sold - yay!)
"Marine Tex 1" Unknown Origin POS 8' Fiberglass Dinghy
https://whichsailboat.com/2014/07/27/catalina-25-review/

Edited by - on

WesAllen
Navigator

Members Avatar

USA
222 Posts

Response Posted - 06/30/2013 : 08:00:32

My anode is mounted near the top/front of the swing keel where it is flat. The contact I think does not have to be on the whole surface as long as there is good contact through the bolt. On mine the anode is used up after about 3 years and needs to be replaced. I also paint the keel with fresh bottom paint before putting the knew anode on. It works for me (and my keel).

Edited by - on

Dave5041
Former Mainsheet Editor

Members Avatar

USA
3758 Posts

Response Posted - 06/30/2013 : 18:19:21

I put anodes near the pivot assembly and the cable attachment. I drilled and tapped holes.

Edited by - on

sethp001
Mainsheet C-25 Tech Editor

Members Avatar

814 Posts

Response Posted - 07/03/2013 : 19:35:47

I don't know why Catalina Direct recommends putting the anode on the trailing edge of the bottom of the keel. I wish I had thought it through before blindly following their directions.

Anyway, I ended up getting a longer bolt that would reach between both sides of the anode and just by torquing it down, was able to bend the bolt until both sides of the anode were flush with the keel. I cut off the extra part of bolt that was sticking out after it was tight. I'll post a picture when I get back to my computer.

Hopefully the bolt won't break later and the anode will still be there at next haul out.

I'll report back what I find next year.

By the way, I didn't have to drill a pilot hole. Just by using a carbide drill bit and going super slow with the drill speed and using lots of gear oil, I was able to get through the cast iron in about an hour. Last year I didn't get anywhere because my drill speed was too fast and I dulled the carbide tip on the bit almost immediately so it wouldn't cut.

Edited by - on

Dave5041
Former Mainsheet Editor

Members Avatar

USA
3758 Posts

Response Posted - 07/06/2013 : 21:18:57

It took me around 10 minutes with a pilot, but that was half way through.

Edited by - on

Voyager
Master Marine Consultant

Members Avatar

USA
5500 Posts

Response Posted - 07/07/2013 : 06:57:38

Seth
The sacrificial anode is good cheap insurance. It protects against galvanic corrosion - due to dissolved salts and dissimilar metals, as well as poorly or improperly grounded 120VAC electrical circuits.
Is your boat in a marina near other boats that may produce stray electric fields? is your boat generally plugged in to shore power? Do you have an outboard or inboard? Is your keel electrically connected by a wire (ground) from your DC or AC circuits? Are you in fresh water or salt?
Each of these factors will influence anode life.

Edited by - on

sethp001
Mainsheet C-25 Tech Editor

Members Avatar

814 Posts

Response Posted - 07/08/2013 : 17:09:37

Here's the photos of the sacrificial anode installed. One of the photos shows the rust barnacles after only one year in fresh water without the anode, despite covering the keel with Rustoleum last year.

You can see how the bolt holding the anode on must be bent in order for both sides to be flush on the keel (although I should have taken a photo from directly aft of the keel to show this better). In the photo from the port side, you can see the extra length of bolt sticking out, which was necessary to initially get the threads of the bolt engaged with the nut on the opposite side, and which after being tightened down would have struck the hull whenever the keel was raised if I had not cut it off.

http://www.flickr.com/photos/81052370@N03/sets/72157634557411958/

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.