Installing the Inner Bottom Layer

Inner bottom ply fitted and glued in
Inner bottom ply fitted and glued in

The bottom of the boat is made up of two plies or layers.  The inner was originally 3/32″ thick by 6 to 8-inch strips, followed by a layer of canvas impregnated with boatyard bedding compound, followed by 1/2″ longitudinal mahogany planks.  This ended up being a 5/8″ thick bottom that did not need to soak up water and swell to a tight, leak-proof fit, like traditional wooden boats do.

We’re replacing the inner ply with 1/8″ marine plywood, then bedding the 1/2″ mahogany planks in epoxy, thereby eliminating the need for the canvas layer which would dry out in about 3-5 years anyway and start leaking.  Our new bottom should have a life of about 30 years or longer if properly cared-for.

Starting at the aft end with a full 8 ft. piece
Starting at the aft end with a full 8 ft. piece

So the first step in that process is to fit the plywood to the bottom frame.  Starting at the aft end, we lay an 8 foot piece up and cut it to the outside of the framework.  As we get further forward, we’ll start laying in 6″ wide strips at a 45° angle to the keel to fit the curve of the forward bottom.

 

 

 

The edges of the forward strips are held adjacent to each other with the help of the intermediate frames.
The edges of the forward strips are held adjacent to each other with the help of the intermediate frames.

The edges of the forward strips are held adjacent to each other with the aid of the intermediate frames which we steam-bent to conform to the curve of the hull some time ago in Using the Boat as a Form.

 

 

 

The forward strips are screwed to the intermediate frames temporarily while the glue sets.
The forward strips are screwed to the intermediate frames temporarily while the glue sets.

After fitting, take it all off, seal the inner face and edges with CPES (Clear Penetrating Epoxy Sealer), and glue it in place with epoxy.  I use 5200 instead of epoxy along the keel for its better elongation properties.  All of this is held in place with monel (look it up–it’s a very corrosion-resistant metal) staples.

 

2 Replies to “Installing the Inner Bottom Layer”

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Discover more from Ashley River Boatworks

Subscribe now to keep reading and get access to the full archive.

Continue reading