18 in the embodiment of fig3 a 3c cutter body arms 22 are not formed integral to base ring 20 and hub 16 and base ring 20 connect through supplemental ring 26 with supplemental arms 28 a 28 b supplemental ring 26 is formed integral with supplemental arms 28 a 28 b extending circumferentially inward 28 b and circumferentially outward 28 a from supplemental ring 26 supplemental ring 26 with integral supplemental arms 28 a 28 b can be formed by casting or other means in the embodiment shown all supplemental arms 28 a extend circumferentially outward from supplemental ring 26 and only some supplemental arms 28 b extend circumferentially inward from supplemental ring 26 cutter body arms 22 connect on one end to base ring 20 and on the other end to supplemental body arms 28 a supplemental body arms 28 b then connect to hub arms 18 thereby connecting base ring 20 to hub 16 base ring 20 supplemental ring 26 and hub 16 are axially symmetric around the axis of rotation with supplemental ring 26 positioned axially forward from base ring 20 and hub 16 positioned axially forward from supplemental ring 26 all connections can be formed for example by welding at weld zones 24 as with cutter head 12 of fig2 a 2c cutter head 12 of fig3 a 3h.