Square Meter: Rudder Fairing

After the rudder was trimmed to shape,  we sanded the surface in order to prep for fairing.  The vacuuming really gets the cloth tight to the tangs.  It is showing its ribs like a starving dog.

To smooth things out we will be adding epoxy thickened with colloidal silica and then outer coatings will be with epoxy thickened with West Systems low density fairing compound (#407) to ease sanding.

On other rudder rebuilds, we have used some foam with many layers of glass cloth to get the strength up.  This doubled over heavy carbon cloth feels as stiff as 1/4 inch steel plate, so glass cloth is unneeded. All we have to do is build up a fair surface.

 

And more fairing...

After several passes with sanding between layers of fairing, the bow was getting close.  But alas, I sanded through to the foam.  I've struck foam!  No major deal.  I scraped out the offending soft spot and filled with Bondo.

The side rails are getting close.  It is to the point were the variations are not visible to the eye.  But if  you run your hand along the rail, you can feel subtle high spots and depressions.
When we feel these areas, we mark them add a spot fairing and next will move to long board sanding.
To this point we have been using a palm sander and a course grit sanding sponge.

Sanded through to foam.

Filled cavity, ready to sand again.

Side rail.