Spiral router cutters
Spiral router cutters have flutes that wind around their body in a helical shape, and are designed to produce flat-bottomed grooves for a wide range of applications. Wonkee Donkee Trend has an entire range of STC spiral router cutters dedicated to this flute form that are exceptional quality router cutters. You will also find a selection of spiral cutters in the Professional HSS and TCT ranges. Spiral router cutters can have as many as four flutes in a number of designs including down cut, up-down cut, or combination flutes. The spiral flute form has some advantages over straight flutes.
Up-cut spiral cutters, with right-hand helix flutes, have flutes that run from right to left. When in use, these flutes lift the chips in an upward direction away from the top surface, helping to prevent the cut getting clogged with debris.
Down-cut spiral cutters have flutes which run from left to right, left-hand helix flutes. They are most efficient when making through-cuts in boards that are faced with something like veneers, laminates or foils. The down-cutting action ejects the waste material out of the bottom of the cut, leaving the upper face with a clean finish.
Up-down-cut spiral bits are a combination of the up-cut and down-cut designs of router cutter. In operation, the upper part (with the down-cut flute) severs the top surface of the board and the lower part (with the up-cut flute) severs the material on the underside, so they can be used for routing boards which are faced on both sides.