What protection do you provide for the centreboard slot to prevent the centreboard grinding away the gelcoat when lifted up and down?

This is a most important technical point and one that does not seem to be adequately addressed by other builders of similar sized boats. On the Norfolk Oyster and Norfolk Gypsy, we fit a hardwood infill section at the base of the centreboard slot. This provides a rubbing surface for the centreboard and overhangs the slot by a reasonable margin each side. This ensures that the infill does not have to be changed more than say, once every 20 years or so. It is easy to imagine that without this protection the fibreglass centreboard casing could become very quickly damaged with the gelcoat being worn away, thereby introducing the danger of possible osmosis. On the Norfolk Smuggler the centreboard exits the hull through a slot which is cast in the cast iron keel which is externally bolted onto the hull. This therefore provides adequate protection for the fibreglass centreboard case within the hull itself. On the Norfolk Trader 45 and 65 the leeboards rub against very heavy duty timber ...  more