Once the rudder is done, this is how we plank one or rather two elevators in the bag ....
Inside the bag the elevators with their reinforcements, including the location of centering pins on the front, then setting the brackets for the servos.
Around a layer of fiber with epoxy resin + Obachi, finally tape to prevent the resin through the necessary places (cracks in the wood) all placed in the body so that the shape is properly applied throughout the drying time.
All in a as possible waterproof bag, with an aspiration to a vacuum compressor that operates at the desired value.
Wait overnight and you will get planked elevators.
There is also the technique of beer case but I will explain it another time, for the planking of the wings may be.
Next step alignment of formers on the work bench for the realization of the fuselage master.