plurality of cutter segments 24 is placed into a keyway or slot 26 and slid into the channel 22 two such keyways are shown in fig2 the keyways of fig2 may be referred to as u201c radial u201d keyways because segments inserted into the keyways are inserted in a radial direction it is to be understood that other configurations of keyways are possible within the scope and spirit of this invention each segment is then slid along the channel in turn until the channel is substantially full of segments steel shims 28 may be used to insure a complete filling of the channel shims 28 of a given thickness may be placed between each segment to reduce the number of carbide segments being used thin steel shims may be used between each segment to prevent carbide against carbide breakage during the severe operating conditions experienced by rock bits a final segment 30 in the nature of a key or locking wedge then slid into the keyway and locked into place with a pin 32 for example into a pin hole 34 alternatively the key 30 may be welded or otherwise secured in place also the spaces in the channel and between the segments may be filled with silver solder or other suitable material if desired silver solder may be used to bond the segments key and cone together as an additional safety factor to minimize the chances of leaving junk down hole in the case of cutting structure failure while the keyways of fig2 were described as radial fig3 a 4 a and 4 b depict an u201c axial u201d keyway in that the segments 24 are inserted into a slot 36 in an axial direction and the slot 36 is.