A subassembly is provided for a pipe lathe. The pipe lathe includes a segmented base ring and a drive gear assembly. The segmented base ring is structured to be removably coupled to a work piece having a perimeter. The subassembly includes a gear ring, a separate ring member, at least one tool mounting portion disposed on the separate ring member. The separate ring member is fastenable to the gear ring, in order that the separate ring member rotates with the gear ring but not independently with respect thereto. A number of tool assemblies mount to the tool mounting portion to machine the work piece. The gear ring includes a plurality of teeth, which cooperate with the drive gear assembly of the pipe lathe to rotate the subassembly about the perimeter of the work piece.