Today I made a sleeve for the bolt that supports the centreplate. The main advantage of a sleeve around the bolt is that it prevents the centreplate box from being crushed or bowed inwards when the nut is tightened. Another good reason for inserting a sleeve within the box is that it makes a watertight seal for the bolt – that’s if it is done properly. Even if the seal doesn’t work, the external washers and flexible sealant should prevent water entering the boat. The plate will rotate on the sleeve rather than the bolt which should eliminate movement of the bolt which would break the external seals.
I just hope there will be no leaks.
Today I also trimmed ragged edges of the centreplate caused by the galvanising, and I re-drilled holes that had been filled by molten zinc. I had to open up three holes in all: one for the lifting and lowering tackle, one for a lifting handle and another for a retaining pin. I took care not to open up the zinc to reveal the iron plate.
When there’s a fine weather slot I’ll put the boat on her side and insert the centreplate.