Removing Zinc Anodes.

[SabreKai]

A bit of a problem, they were put on with mild steel nuts over stainless bolts, and the nuts are almost round. Impossible to get at from the side as they are recessed into the anode, and I can't get enough leverage with Vice-grips if I put them on from the end.

So. How do I get them off? Can the zinc be cut away with a cut off disk? Melted off with a torch? If I can get at them from the side, a nut buster would do the job or a chisel. Heck even the grips from the side might do it with a little application of heat.

Suggestions would be appreciated. I got the small ones off the rudder, but the four big ones on the keel need to go too.

[wetsail1]

Beat it with a large hammer

[D.D.]

A dremel is your best friend.

[djmarchand]

Or grind it with an angle grinder.

David

[SabreKai]

I came to that conclusion myself. Angle grinder with thin disks. Cut in parallel to the iron bar inside all around the end and then across. Chisel and a hammer and the zinc came off ok. Not fun stuff to grind, it smears like lead and aluminum and gums up the disk. The thinner the better. I used 1/16 masonary disks.

Once the mass of zinc was gone, application of propane torch and vice grips got them off OK.

[Boracay]

I've sheared off one or two nuts in my day. When I don't want to it's ridiculously easy.

So I'd just put a tight socket on the nut with a decent size handle and lean on it. Should shear right off.

Then grind off the stump and weld a suitable 316 bolt on. Go for something like 5/16".

You've an Offshore 38, right? the've been a few reports of skeg failure on larger versions of similar designs. My impression is that the close proximity of the propeller to the skeg can cause electrolysis which would not help.

I'd suggest mounting a largish anode on the skeg right behind the prop and making sure the paint on the skeg, rudder and surrounding are are up to scratch. Propspeed on the prop seems to help.

And just in case the stray electrical currents get a bit out of hand I've found a big anode close to the bottom of the keel in the middle can be a good idea. Don't ask.