The leading edges of the elevators are curved to fit into the trailing edge of the horizontal stabilizer along the hinge line. This is done by rolling a smooth bend into the top and bottom skins of the elevator.
In the image above, a wooden dowel has been taped to the front edge of the bottom skin. This will be used to place a bending force on the skin to give it its curve. This wide section of leading edge will require quite a bit of torque to bend. Just twisting on the dowel will not be enough. I’m using a large vice-grip to provide some leverage:
Here’s a view along the dowel before doing the bending:
And here’s what the skin looks like after the first pass:
It took quite a bit more bending, especially on the very edge of the skins to get the top and bottom to align flat against each other (I spent several hours working on this). I’m thinking that the left elevator will go much more quickly now that I’ve done it once before. Here are some pictures of the completed elevator, including the rod-end bearings that will provide the hinge line for the elevator movement: