I’m still churning through all the prep work for the fuselage parts. Today I managed to complete the countersinking on the F-717 Lower Longerons. I also dimpled and deburred the entire right skin. The most important part of this job was to ensure the correct holes were being dimpled. 
This picture shows probably the most notable part of the day. I used my screw dimple die to from the #10 dimple. This interfaces with the the tank attach bracket stiffener. The skin/longeron under this dimple will be countersunk.
