The insert was removed
The adjacent blades were moved clockwise and counterclockwise
and the middle blade is being released now
The middle blade/locking blade was removed
The middle/locking blade
The teeth are on the both side of the locking blades, on the picture above only the convex blade side teeth are shown but on the concave blade side the teeth are present as well.
When the middle/locking blade is out of the groove the next blades can be put out.
The set of locking blades is shown below. On the right hand side is the locking balde (the teeth are visible from both blde side). The blades with numbers are these ones which adhere to the locking blade form rigth and left hand side.
The locking set in removed, so just now the rest of the blades will be dissasembled. It takes some time as it has to be done piece by piece,
The rest stages were rebladed in exactly the same way. 
