Solution for the Cutting Vibration in Milling

In CNC milling, vibration may occur due to the limitations of cutting tools, tool holders, machine, workpieces or fixtures, which will have certain adverse effects on machining accuracy, surface quality, and machining efficiency. To reduce cutting vibration, some relevant factors need to be considered. The following information is a comprehensive summary for your reference.

Fixtures with poor rigidity

  • Evaluate the direction of the cutting force, and we can provide sufficient support or improve the fixture
  • Reduce cutting force by reducing the depth of cut ap
  • Choose sparse tooth and unequal pitch milling cutters with sharper cutting edges
  • Choose a groove type with a small corner radii and small parallel lands
  • Choose fine-grain uncoated inserts or thinner coating inserts
  • Avoid processing when the support of the workpiece is not enough to resist the cutting force

Workpieces with poor axial rigidity

  • Consider using a square shoulder mill with a positive rake angle (90° entering angle)
  • Choose the inserts with L insert geometry
  • Reduce axial cutting forces: smaller depth of cut, smaller corner radii and parallel land
  • Choose coarse-pitch cutter with differential pitch
  • Check tool wear
  • Check the runout of the tool holder
  • Improve tool clamping

Tool overhang is too long

  • Minimize overhang
  • Use coarse-pitch cutter with differential pitch
  • Balanced radial and axial cutting forces -45° entering angle, large nose arc radius or round insert milling cutter
  • Increase the feed per tooth
  • Use light cutting insert geometry
  • Reduce the axial depth of cut, af
  • Adopt up-cut milling in finishing
  • Use an extension rod with anti-vibration function
  • For solid carbide end mills and exchangeable head milling cutters, try to use tools with fewer teeth and/or larger helix angles.

Use a spindle with poor rigidity to mill the square shoulder

  • Choose the milling cutter with the smallest diameter possible
  • Choose light-cutting milling cutters and inserts with sharp cutting edges
  • Try up-milling
  • Check the spindle deformation to see if it is within the acceptable range of the machine

Unstable table feed

  • Try up-milling
  • Tighten the feed mechanism of the machines: For CNC machines, adjust the feed screw
  • For traditional machines, adjust the locking screw or replace the ball screw

Cutting parameters

  • Reduce cutting speed (vc)
  • Increase feed (fz)
  • Change the depth of cutting (ap)

Poor stability

  • Shorten the overhang
  • Improve stability

Vibration in the corner

  • Large programming corner radii at a lower feed rate

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