Locating Zincs
Tom: I use zinc anodes on my keel. The water in Middle River gets saltier as the summer progresses. I actually use 2 sets at a time, replacing one set every other year. One of each set is on each side of the keel. I drilled thru the keel and inserted pieces of 1/4 inch diameter stainless steel threaded rod through the it below and aft of the silicon bronze pin that the keel rotates on. Remember, you don't want the zincs to interfere with the bottom of the hull when the centerboard rotates downward. The second set of zincs is about 1/2 inch aft of the first set. I did notice in Catalina Direct's sketches, that they show the zinc's near the pin for the cable, near the bottom of the centerboard. I have carefully inspected my cable clevis pins and the eye piece on the centerboard and never noticed any corosion there, so the zincs must be protecting this area too. You, of course, want the zincs to come in good electrical contact with the cast iron of the keel without having any paint between the keel and zinc. I use stainless steel nuts to hold the zincs onto the threaded rod. I counterbore the zincs so that a socket can be used to tighten the nuts. I then silicone seal the counterbore around the nuts so that the zincs are smooth in the water. I use the 2 3/4 inch diameter dome shaped zincs. I wish you had asked this question last week, I would have sent you a photo. Now Key Largo boat is floating in her slip. Aldo
