Types of CNC Router Bits

What is an upcut router bit?

Upcut tool geometry has a helix that pushes the chips up. The benefit of these tools is the chips are removed out of the material being cut. They also create a good finish on the bottom edge of wood minimizing the chance of chipping or fraying.

Upcut helix

Upcut helix

What is a downcut router bit?

Downcut tool geometry has a helix that pushes the chips down. This has a couple benefits. These tools leave a good finish on the top edge of wood minimizing the chance of chipping or fraying. Another benefit since the chips are being forced downward this helps with keeping the material from pulling up if workholding limitations exist.

Downcut Helix

Downcut Helix

What is a compression router bit?

Compression cutters are a combination of up and downcut geometry in one… sounds complicated I know but its not! The compression cutter is designed to give the best possible edge finish on the top and bottom of the wood especially when doing a peripheral cut.

Compression Helix

Compression Helix

What is a rougher router bit?

Roughing tools are designed to be used at high feed rates and to be used before a finishing profile cutter. The ripples on the flute break the chips up into small pieces which reduce heat and allow for an extremely quiet and smooth cut however these cutters will leave a rippled edge if not finished with a profile cutter. Roughers can come in Upcut, Downcut, or Compression Helix geometries.

Rougher with Compression Helix

Rougher with Compression Helix

What is a finisher router bit?

Finishing tools are designed to give that smooth edge finish as the cutting edge on the flutes is precisely ground perfectly smooth. These tools can be used by themselves or after a roughing tool. To achieve a quality cut over and over we recommend using a roughing tool first followed by a finishing tool if your cnc is equipped with a tool changer.

Finisher with Upcut Helix

Finisher with Upcut Helix

What is a ballnose router bit?

Ball nose tools have a radius on the tip that is the size of the cutting diameter. These tools are used for 3D routing and cutting slots with rounded bottoms or for cutting a radius on an inside corner.

Ballnose with Upcut Helix

Ballnose with Upcut Helix

What is a tapered ballnose router bit?

Tapered ball nose spirals are used mostly for 3D carving. The benefit of the taper design is it adds strength to the tool minimizing deflection. Deflection is when the tool has a bit of flex when cutting leaving for an undesirable cut and lower tool life.

Tapered Ballnose with Upcut Helix

Tapered Ballnose with Upcut Helix

What is a low helix router bit?

Low Helix cutters are designed to produce less of a lifting effect on the material being cut since the flute has a less drastic upspiral. These cutters come in roughing and finishing style flutes.

Low Helix with Downcut Geometry

Low Helix with Downcut Geometry