Cabin Trunk Details....
Mast thru deck construction

A Thru-Deck Collar is continuously welded to the trunk or cabin framework where the mast penetrates. The collar extends at least 2" above the trunk or deck top. Inside, it extends to a depth equal to the width of the framework. Note that this component is not part of the mast it is part of the cabin structure.

Compression posts are 1/2" diameter steel rods that are plug welded on the interior of the mast where the mast aligns with the deck framing, similar to the compression post at the spreaders.

A Mast Collar Doubler, similar to the doubler at the mast head and spreaders, is used where the mast penetrates the trunk or deck framing.

Mast Clearance is necessary around the mast for installation or removal from the boat. A reasonable amount of clearance is necessary. The mast can be held in position by wood shims. A mast boot is necessary to prevent water from entering the boat.

Also shown on this drawing is the center divider, used to fabricate the mast. Lighting hole in the center divider are shown.

Deck structure of the boat hull is shown for clarity.

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