A excavating assembly for milling and/or scarifying a road surface or ground to be milled, wherein said excavating assembly comprises a support structure delimiting a compartment, said support structure comprises a compartment opening adapted to face said road surface or ground to be milled; said excavating assembly further comprises a cutter, said cutter being housed in said compartment of the support structure so as to be rotatable about a cutter axis; said cutter protrudes from said compartment through said compartment opening in order to mill said road surface or ground to be milled; said excavating assembly further comprises a cutter movement unit connected to said cutter; said cutter movement unit being supported by said support structure; said excavating assembly further comprises at least one support element adapted to rest on said road surface or ground to be milled during the milling operations; said at least one support element is separate from said support structure; characterized in that said cutter comprises a cutter axle extension protruding from said support structure thus extending said cutter axis; said support element comprises an eccentric plate seat; said eccentric plate seat rotatably houses an eccentric plate so as to allow said eccentric plate to rotate about a support element axis (X'); said eccentric plate comprises a cutter axle extension seat; said cutter axle extension seat houses said cutter axle extension so as to be freely rotatable; said cutter axis, as extended by said cutter axle extension, is eccentric with respect to said support element axis (X'), defining a predetermined eccentricity (e); said excavating assembly further comprises an eccentric plate movement unit connected to said eccentric plate for moving said eccentric plate about said support element axis (X'). said excavating assembly comprises a support structure delimiting a compartment, said support structure comprises a compartment opening adapted to face said road surface or ground to be milled; said excavating assembly further comprises a cutter, said cutter being housed in said compartment of the support structure so as to be rotatable about a cutter axis; said cutter protrudes from said compartment through said compartment opening in order to mill said road surface or ground to be milled; said excavating assembly further comprises a cutter movement unit connected to said cutter; said cutter movement unit being supported by said support structure; said excavating assembly further comprises at least one support element adapted to rest on said road surface or ground to be milled during the milling operations; said at least one support element is separate from said support structure; characterized in that said cutter comprises a cutter axle extension protruding from said support structure thus extending said cutter axis; said support element comprises an eccentric plate seat; said eccentric plate seat rotatably houses an eccentric plate so as to allow said eccentric plate to rotate about a support element axis (X'); said eccentric plate comprises a cutter axle extension seat; said cutter axle extension seat houses said cutter axle extension so as to be freely rotatable; said cutter axis, as extended by said cutter axle extension, is eccentric with respect to said support element axis (X'), defining a predetermined eccentricity (e); said excavating assembly further comprises an eccentric plate movement unit connected to said eccentric plate for moving said eccentric plate about said support element axis (X').