Originally Posted by Gorey
The marina put on a class on bonding of thru hulls. He told me that the older boats used a superior type of bronze that is highly resistant to corrosion.
Interesting... I also noticed the thickness was greater; the old fitting weighed at least 1/3 more than the new one. Could you explain why you would want to bond all of your thru-hulls to a zinc? I thought that any isolated thru-hull (with no direct connection to the electrical; like cockpit/sink drains) should be left without a bonding wire to keep it electrically isolated.