I removed this centerboard for inspection for the first time 32 years after it was installed in my Potter 14 Manatee, #234, built in 1967 by HMS Marine. The boat is one of the first generation of US-built Potters.
The galvanized board is in very good condition, with only surface
rust in the pivot slot and on the leading edge. (What appears to be
a rust stain across the lower end of the arm is actually varnish.)
This board is made from a single steel plate, with no weld joints,
and weighs about 65 lb. (Some later boards have a welded-on arm.)
The lower leading edge is a little rough but has none of the big
dings that I expected to find after many encounters with rocks and
other unyielding underwater objects.
The 3/8-inch-diameter carriage bolt that the centerboard pivots on was rusty and visibly worn down on the upper surface. I reamed the hole in the trunk and replaced the carriage bolt with a 7/16-inch stainless bolt, fender washers, and a self-locking nut, sealing the interfaces with Life-Calk. The slot in the centerboard is large enough to accommodate even a 1/2-inch bolt.