.....Again, marking a center line along the leading edge of the fin, over the top of the fin/rudder joint, and down the trailing edge of the rudder will help you accomplish symetrical airfoil sections on both sides of the assembly......

Yes absolutely the drawing of a centerline on the leading edge and trailing edge is essential to make sure you're tapering the control surface evenly on both sides. As long as you can see that pencil line, you know you haven't over-sanded the surface. We will see the same thing on the wing when we go to sand the L.E., T.E. and control surfaces.

I use a sanding wheel attached to my Dremel scroll saw for shaping small parts, and a long board with sandpaper glued to it for larger surfaces. I even use my trusty orbital sander, (with a light touch) to sand larger surfaces. When you have those centerlines it makes all the difference. This is something I've been doing for so long that I didn't even think to mention it, but it's very important. Thanks "billberry" for your technique.

Duane