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● NC-200A1 The possible reasons to cause cutter vibrate

Ans:

There are two possible reasons :
One is mechanical reason cause the cutter vibrate , Another is NC feeding problem.

  1.   One is the top feeding distance (space) is not enough (Mininum: 25mm) ,
    If the top feeding distance (space) is not enough, it will cause the feeding in the inner hole , then cause the cutter vibrate , Cutter vibrate so cause surface is bad.
      Maybe Y axis slideway taper gib loosen or Y axis slide way taper gib loose or Ram taper gib loose or cutter dull or any mechanical reason cause the bad surface. Maybe you can change another cutter and another workpiece to test cutting ,
    If another workpiece cutting is OK. then you need to check what happen about your cutter and workpiece material or cutting condition etc..
  2.   Second reason is just related to NC servo motor feeding problem , 
    Please take out workpiece to test run machine feeding and put a dial gauge on the back of machine base to check the table feeding condition.
      You can set the back off at 0 and set feed rate 0.05 then test each feeding is regular or not ,Most important is the feeding is continuous and final point is always at same position or not ?Please change speed to High / Low different speed to test run again.  Besides please set tool back off 0.5mm , feeding 0.05mm and test again the running condition, If the machine test try run is normal , It mean PLC computer is normal, No problem. Then you need to check what reason cause the cutter vibrate . If it is unnormal (Not continuous feeding) , then just check the feeding sensor.
  3.   If you find the feeding is unnormal (not continuous) during test running program ,
    The possible reason is the spindle feeding sensor singal unnormal. Please open the right/upper plate then you can see two sensors on the spindle shaft ,
      Near machine front side is for feeding and top point checking purpose , Near the flywheel (backward) which is for tool back off purpose.Normally the forward feeding sensor must light ON one time each stroke.
      If the sensor singal is unstable , it is possible to cause the feeding not stable because PLC controller need the feeding sensor singal then just ask Y axis servo motor feed.