A close inspection of ‘Minnow’s’ rudder revealed minute gaps between the fibreglassing and the metal strip protecting the leading edge. Instead of being encapsulated with fibreglass folded over the edge, the builder appears of have taken the cloth as far as the brass capping piece. That may have been OK when built, but over time tiny gaps have developed. The result is that water could enter the plywood, possibly causing delaminating. Water permanently trapped within the sheathing would not be good for the plywood.
Well, today, I cleaned up the leading edge and filled the gaps with epoxy. Providing water tightness can be maintained, there should be no further problem. Because the temperature was only 9 degrees Celsius I made a tent from a tarpaulin that I arranged over the rudder for trapping warm air from my miniature blow heater and an electric inspection lamp. By late afternoon the epoxy had hardened.