Cymen Vig

I’ve been working on replacement rudders for Atta. A rotating model makes the design much easier to explain than a collection of screenshots, especially when looking at how the stock, internal supports and blade fit together. This viewer shows the current FreeCAD design, with colors preserved and separate views for the port and starboard rudders.

Open the viewer full-screen. Drag to rotate, scroll or pinch to zoom, and use the view menu to switch between the exterior, internal structure and upper details. There is also an automatic rotation button and a GLB download for each view.

The design keeps roughly the original rudder outline and size. The section starts from a NACA 0018 profile near the top and transitions to NACA 0015 farther down the blade, with local changes around the stock and upper clearance area. The current model includes a 5 mm trailing-edge candidate and a finite tip. These are still design details to check, rather than a finished construction specification.

The plan is to CNC-cut the core components, assemble them around the stock and internal structure, then laminate the outside with fiberglass and fair it using templates. I’m working through the starboard trunk installation first so I can check alignment and clearance with the new stock before removing the old port trunk.

The colors identify components and reserved spaces; they don’t represent a finalized material or laminate schedule. The cutaway views hide selected parts and make others transparent to expose the structure. Laminate details, joints, hull fit and tip closure still need to be resolved. This is a snapshot of the work in progress, not a construction-ready or strength-certified design.

For a copy you can send to someone, download the portable viewer ZIP (4.3 MB). Extract it and open the HTML file in a browser; FreeCAD is not required. Both versions use Google’s model-viewer library, which needs an internet connection.