In CNC milling, vibration may occur due to the limitations of cutting tools, tool holders, machine tools, workpieces or fixtures, which will have certain adverse effects on machining accuracy, surface quality, and machining efficiency. To reduce cutting vibration, relevant factors need to be considered. The following is a comprehensive summary for your reference.
1Poorly rigid fixture
1) Evaluate the direction of the cutting force, provide sufficient support or improve the fixture
2) Reduce cutting force by reducing the depth of cut ap
3) Choose sparse tooth and unequal pitch milling cutters with sharper cutting edges
4) Choose a groove type with a small arc radius of the tool tip and a small parallel land
5) Choose fine-grain uncoated blades or thin-coated blades
6) Avoid processing when the support of the workpiece is not enough to resist the cutting force
2Workpieces with poor axial rigidity
1) Consider using a square shoulder milling cutter with a positive rake angle (90° entering angle)
2) Choose the blade with L groove shape
3) Reduce axial cutting force: smaller depth of cut, smaller tip radius and parallel land
4) Choose sparse tooth milling cutter with unequal pitch
5) Check tool wear
6) Check the runout of the tool holder
7) Improve tool clamping
3 Tool overhang is too long
1) Minimize overhang
2) Use sparse tooth milling cutter with unequal pitch
3) Balanced radial and axial cutting forces -45° entering angle, large nose arc radius or round insert milling cutter
4) Increase the feed per tooth
5) Use light cutting insert geometry
6) Reduce the axial depth of cut af
7) Adopt up-cut milling in finishing
8) Use an extension rod with anti-vibration function
9) For solid carbide end mills and interchangeable head milling cutters, try to use milling cutters with fewer teeth and/or larger helix angles
4 Use a poorly rigid spindle to mill the square shoulder
1) Choose the milling cutter with the smallest diameter possible
2) Choose light-cutting milling cutters and inserts with sharp cutting edges
3) Try up-milling
4) Check the spindle deformation to see if it is within the acceptable range of the machine tool
5 Unstable table feed
1) Try up-milling
2) Tighten the feed mechanism of the machine tool: For CNC machine tools, adjust the feed screw
3) For traditional machine tools, adjust the locking screw or replace the ball screw
6 cutting parameters
1) Reduce cutting speed (vc)
2) Increase feed (fz)
3) Change the depth of cut ap
7 Poor stability
1) Shorten the overhang
2) Improve stability
8 Vibration in the corner
Large programming fillet at a lower feed rate
