Properly secure the knives in the cutterhead and check that safety set screws are locked in before mounting on the machine.
Loosen out the safety set screws, use the 3mm hexagon spanner.
Use the hexagon spanner to punch, gently tap down, and slide the segmented gib to release the knife.
Install new knife or reverse current knife for new edge. Make sure the planing knife is properly seated on the bead.
Punch the segment gib again, it will automatically secure the knife precisely in place.
Tighten the two safety set screws.