Best for achieving smooth finish on hard plastics. Cutting Diameter: 5/16 Cutting Height: 1 Shank Diameter: 5/16 Overall Length: 2-1/2 Flutes: 3 Low Helix bits perform a more lateral movement with less lift resulting in a smoother finish. These bits are a better choice for hard plastics such as acrylic and phenolic. Down cut endmills shear in a downward direction causing the uppermost layer of the material to be pressed down against the material just below it. This motion leaves a perfectly clean top surface edge. A concentration of wood chips in the work path will occur. Hose away excess wood chips to prevent bit breakage. Highlights: - For CNC milling and routing on challenging materials where a clean top surface edge of material is required - Premium C3 micro-grain solid tungsten carbide for a high-performance industrial quality tool - For use on CNC, table mount and handheld routers - Polished to a mirror finish from a solid carbide rod for precision & accuracy - 3 flute design for more efficient performance on hardwoods and non-ferrous alloys Item Includes: 1 CNC Endmill Router Bit To get a smooth finish in hard plastics like acrylic with your CNC router, use a low helix spiral end mill. The modified cutter angle produces a better finish in plastics than standard spiral bits. Downcut bits pull chips downward, producing a clean top edge in your parts. Consequently, the chips accumulate in the cut path and should be removed to prevent bit breakage. Low helix bits require slower feed speeds than normal high helix bits.