points by hinges 10 movably pinned to the trusses t 1 t 2 which are fixedly attached to the bucket 1 as by welding riveting bolts etc and to the frame assembly 8 such that the gap 3 see fig2 b may be adjusted by a hydraulic actuator 11 the action of which is shown more clearly in fig4 and 5 hydraulic hoses 6 and 7 provide hydraulic power for rotating the hydraulic motor transmission 9 either clockwise or counterclockwise as desired for rotation of the disk 2 return or leakage hose 5 provides a path for removal of fluid leakage inside the hydraulic motor transmission 9 hydraulic actuator 11 powered by hydraulic hoses 12 13 is movably attached to bucket 1 by truss t 3 also fixedly attached to bucket 1 at pin p 5 the movable shaft of actuator 11 is attached to frame 8 by pin p 6 and is shown fully extended in fig2 a to produce a minimum gap 3 thus frame assembly 8 with hydraulic motor transmission 9 disk 2 attached may be moved relative to the cut out bottom of bucket 1 so as to adjust the gap 3 therebetween the hinges 10 u201c swinging u201d frame assembly 8 and disk 2 attached thereto toward or away from the bottom of bucket 1 the length of the hinges 10 determines the maximum dimension of gap 3 it will be appreciated that during all of the herein described operations stick s is in.