We engineered and manufactured a structure to limit the mast movement on the X79 keel boat, whilst it is sailing under load. The lead through stainless steel structure on the X79 deck is much bigger than the old thin mast. Most owners use wooden wedges to support the mast to improve trimming, but these need regular maintenance, and have the danger of working loose in heavy seas.
We manufacture a part from thickened epoxy with glass fibre reinforcements. It slides on to the mast before it is stepped, and then slides into the deck structure. The tight fit of the mast allows the owner to keep tighter rig tension, and maintain a straighter jib luff for best upwind angles.