Anodes

[Roach1948]

Up till now Roach has only had a button anode on the rudder like the one shown below. She never seems to have had any galvanic problems.

The electrician tells me that I should have a linked anode that joins the shaft, sterntube to the engine, but these pear anodes are HUGE and quite expensive too. They also have bolt holes too far apart as they whould need to straddle the frames in my bilge making a backing pad problematic. I was wondering what other wooden boat users have? Am I unique in not having a linked system? If I do need one could I get away with a cheap VETUS style anode - they are about 15cm long and 7cm wide and would make installing a backing pad etc easier as well as being miles cheaper than the smalled MgDuff Pear.

Intersted to hear your points of view as I have no idea about these sorts of things!

 

[Casey]

I was recently talking to John Lilley about ( http://www.seasurveys.co.uk/ ) this very subject and took some advice from him. He said that if you get anodic protection wrong it can be very expensive and he had recently seen the deadwood of one boat eroded away because the owner connected the anodes up incorrectly. I would suggest you take professional advice from John or another wooden boat specialist.

 

[Roach1948]

Thanks, I have yet to have my pre-launch survey, so maybe I will wait till my surveyor gives a verdict - it does not take long to add an anode. I would also say that I am on a swinging mooring and have a no charging facilities from the mains.

 

[Peterduck]

Not all boats require anodes. My old boat used up two anodes each year but a friend of mine had his wooden boat in the same marina, had never fitted an anode and had no problems. A boat living on a swing mooring is less likely to need an anode than one living in a marina where stray electrical currents are more prevalent. I would certainly agree with talking to John Lilley about this very complex issue.
Peter.

 

[Eastermaid]

If you are worried about shaft/prop fit a nut anode (search google ) My last boat had softening around anodes which were fitted on hull. So removed replaced with nut anode just to protect prop/shaft. A fitting needs to be connected to anode to be protected So unless you cross bond all skin fittings etc you will not protect everything.