Power tool for forming a channel in a work surface and accessories therefor

A power tool for forming a channel in a concrete work surface comprising:

• a first section carrying a rotatable shaft extending along a shaft axis;
• a cutting disc having a substantially circular blade provided on the rotatable shaft by receiving the rotatable shaft through a circular opening of the cutting disc;
• a first support portion on one side of the cutting disc and a second support portion on the opposite side of the cutting disc,
• the first support portion having a first end surface perpendicular to the shaft axis and an opposing non-parallel second end surface,
• the second support portion having a first end surface perpendicular to the shaft axis and an opposing non-parallel second end surface,
• the first and second support portions cooperating to hold the cutting disc at an oblique angle relative to the shaft axis,
• each of the second end surfaces of the first and second support portions having a plurality of first locking features and second locking features, respectively,
• the plurality of first locking features of the first support portion and second locking features of the second support portion extend through and are spaced about the circular opening of the cutting disc whereby such locking features cooperate to resist relative rotation of the first and second support portions,
• wherein the plurality of first locking features of the first support portion comprise a first set of projections and the plurality of second locking features of the second support portion comprise a second set of projections;
• a second section for engaging the work surface, the first section being movable relative to the second section such that the cutting disc can be moved into and out of engagement with the work surface in use,
• wherein an active portion of the periphery of the cutting disc, being the part of the periphery furthest from the rotatable shaft in the direction of the work surface, oscillates along an axis parallel to the shaft axis when the rotatable shaft rotates.