Altamira – Aft Cabin Work March Update

The athwartships laminated floor beam (or floor timber) is finished. I was able to get the beam ends out to the chines and the ends are supported by the thick fiberglass hull bottom layups at the chines. There are no chine logs. The beam is mainly supported by and is keyed to the four longitudinal stringers. You can see the edge grain of extensions of an existing 3/4″ plywood sister to starboard (port was done the same), and six new 1/2″ AC plywood laminations for the new beam. All plywood end grain is epoxy sealed. The epoxy used for sealing surface and end grain is West System 105 resin and 206 slow hardener. West System 403 filler is added to the resin for laminating and filling. I laminated one layer each work day. I left the exposed face of each new layer unsealed – coating that face when the next layer is added to eliminate any potential amine blush adhesion problems. Each layer was clamped for curing using 1 1/4″ narrow crown staples delivered via a Ryobi cordless narrow crown stapler – staples were not removed. The photo shows white painted cleats on the forward face of the last layer – to support the floor sections, which will be removable, though mostly covered by new berths and cabinets.

It is good to be done with the below the floor work. The new beam will provide a fine foundation for the new bulkhead and a great place to set the raising jacks and supports. The thinner laminated beam visible at the bottom right was done 9 years ago to repair rot caused by rain water leakage. The sawn edges of the floor boards (setting atop the batteries) have been sealed with neat (no filler) epoxy. No wood can be left bare on a boat – must be sealed/coated and/or painted to prevent mold. Neat epoxy is an excellent sealer/coating for wood – perfect for concealed and non-finished areas. It is also an excellent bare wood primer for one-part polyurethane paints, although care must be taken during application to minimize the need for sanding prior to paint application.

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