The Rudder Stiffeners are cut from six pieces of aluminum angle that are about 3 feet long and contain special pre-punched markings that define where the angles of the flanges need to be trimmed. The picture below is of the stiffeners once I cut them apart with a pair of snips. I have labeled them A through H, making sure I have one for each side of the skin. There are eight per side, for a total of 16 for the rudder.
The main purpose for the stiffeners is to "stiffens" the thin rudder skin to keep it from flexing to much. There are only two end-ribs for the rudder, one on top and one on the bottom.
This week I started marking, cutting, and breaking the edges of the stiffeners. The picture below shows a before and after of the aluminum angle. If you look close at the one on top, you can see the semicircle notches that Vans made and the lines drawn to connect the marks to create the correct trim lines for each stiffener. The black line connects the the semicircles.
I use the band saw to ruff cut to the outside of the black line, then my bench grinder to get down the thickness of the line and finished them up on the Scotch-Brite wheel to break the edges. From there its hand work with red Scotch-Brite to smooth it all up.
