The rudders on a lot of older airplane designs seem kind of small by today’s standards.  A lot of guys nowadays like to hover or do other demanding stunts which require a lot of rudder control.  The older planes are still good planes, but maybe you want to build yours with a bigger rudder.  Here’s the rudder from an RCM Basic Bipe kit I cut out for a customer.

I know what you’re thinking.  This rudder seems really slim for a sporty biplane.  The first idea that occurs to most of us is to add balsa to the trailing edge to make it bigger, as shown in this drawing.  I traced around the rudder and indicated the area where you would want to add balsa wood, following this theory.

You could theoretically accomplish this by using the original rudder as a template for cutting out the balsa, then glue it to the trailing edge.  But there’s a much simpler way.  Glue a straight piece on the leading edge to make the rudder as wide as you want it.

I know, this seems pretty obvious.  But I’m sure there’s a beginner out there wondering if it would work.  Yes, it does.  All you need to do is glue the strip on, then sand the edges so it lines up properly with the top of the vertical stabilizer and the bottom of the fuselage.