- Maintain superior precision, speed, and quality in your cnc machine projects with the RC-1145 & RC-1148 Amana Tool RCK-56 Decorative Insert V-Groove Replacement Knife. Specifically designed to restore clean, accurate cutting performance, this replacement blade ensures your v-groove bit continues to deliver sharp, reliable results with maximum efficiency. Amana Tool Amana Tool’s cnc machine router bits are crafted from premium sub-micron grain carbide, ensuring exceptional durability and precision. Utilising an advanced edge processing system, each router bit is finished with a mirror-like polish and a razor-sharp cutting edge. This meticulous process results in clean, precise cuts, minimal chip re-welding, an outstanding surface finish, and. most importantly. an extended tool life.