Sailboat Keel Patterns
How to Fabricate

Keel Patterns

The below drawing is a scaled representation of the "Bezier 28" developed keel plating. This pattern is designed to lie flat on the aluminum sheet material from which the keel plating will be formed. The pattern contains numerous color coded lines.

• Black - Perimeter or outline of the Keel
• Blue - Forming lines at one (1) degree bend angles.
• Magenta - Location of Frames
• Red - Prop Cutout
• Green - Template Forming Guide Lines

The patterns are supplied full size on 24" x 65" paper. Since the full size keel is much larger than this, individual segments of the keel are printed on separate sheets. The below drawing shows the individual segments nested loosely together.

Forming the Keel

All the lines represented on the patterns will need to be transferred to the keel material. They all serve different purposes. Every one is essential at some point in the fabrication, forming and fitting of the keel assembly.

The keel plating is fabricated in two pieces per side as shown in the below drawing. Consisting of the nose and aft sections. The keel is formed by the same bending methods use when forming the Bezier curved section of the hull. The only real difference is the physical size of the patterns. The Bezier curve sections for the hull plating are smaller and easier to handle compared to the larger keel patterns.

Keel Forming Templates

To assist in the forming of the nose section of the keel, templates are supplied at positions marked by Green lines. These section templates, shown in the sketch below, are positioned on the Green lines during the press break forming process to verify the sections shape at this particular location. It should be noted that the shape of the nose varies from the top of the keel to the bottom.

After forming the nose section fit the formed keel plating onto the framework of the hull. The Magenta lines will come into play here. These lines match the frame positions.

As mentioned before, the eye is a very discriminating instrument. It will prove invaluable when constructing and fitting the keel!

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