Sacrificing your anodes!!

[Tim Osborne]

Dear All,I'm just about to re-launch my boat after the winter break - yes spring is really on it's way in the UK !?!? - and this year my boat will be moored on a pontoon berth. Got fed up with the 'slipway panic' on Sunday evenings!Anyway my question is - has anyone added or needed to add a sacrificial anode to their boat to stop masts, booms etc disappearing over the ensuing months, and if so, how? My plan was to simply hang a lump of zinc on a wire, off the pushpit and earth it to the mast. This is cetainly not my area of expertise but I'm sure there is someone out there who's been there already and is wearing the T Shirt!Needless to say this will be in salt water.Thanks in advance for any advice.Tim Osborne'Pelagia'

 

[R.W.Landau]

Problem already?

Are you having problems with the mast and boom? Is it just around the fittings and hardware?Dissimilar metals cause galvanic action. You will not stop this corrosion with a zinc. You will need to isolate the dissimilar metals using a antioxidizing compound on the fasteners and a means of isolating the fitting or hardware. Paint, silicone, or something so that the two metals do not touch.If you are having problems with the mast corroding where there is no hardware, I would recommend coating the mast with penetrol or paint. If the mast looses the coating that is factory applied, It will corrode due to the salt.I would hesitate throwing a zinc over board connected to the rigging. The rigging should be bonded to the DC ground. That way only one point needs to be protected for electrolysis. If you throw the zinc over the side, you may actually create your own battery of different potentials between the boats grounding and the zinc you threw over. This may cause more problem than help. I would make sure your present grounding and bonding is correctly done. Have a great UK sailing seasonr.w.landau

 

[Tim Osborne]

No Problems but............

R.W. Thanks for your detailed response - there are no problems at present but this year is the first time the boat will be afloat all season - so I was just checking out if any further protection was necessary - prevention / cure - trying to get them in the right order for once.Thanks again anyway - we'll see what happens...........Tim Osborne

 

[Alan]

eyes wide shut

I am no expert, however my boat ('94h26)stays in the water except for winter haul-out. The previous owners also kept it in. There is minimal corrosion to parts of the rudder, a little pitting, and thats all. The swing keel seems to be working well so hopefully the bolt it pivots on is also intact as it can not be seen unless removed (expensive). I have been told that there should be some sort of ground but I fail to see where it is. alan

 

[Per Albinsson]

Save your zinc

Corrosion problems occur when you mix different metals and put them in an electrolyte (salt water). If you lift your outboard out of the water you just will have one metal (stainless steel), in the electrolyte and then nothing will happen. Dont worry about your spars, my (somewhat limited) experience of British summer tells me that eventual salt spray on these parts will be washed away by rain before saturday.Per Albinsson / AMFI