Common Problems and Solutions in PCB Drilling

• Drill Plugging Issues:

  Reasons:

  • Not using a cover plate or improper drilling parameters selection.

  Solutions:

  • Utilize a suitable cover plate.
  • Adjust the feed rate or drill speed accordingly.

• Rough Hole Wall Problem:

  Causes:

  • Excessive feed rate variation.
  • High feed rate.
  • Incorrect cover material selection.
  • Inadequate vacuum at the fixed bit.
  • Improper retraction rate.
  • Damage to the cutting edge or bit corner.
  • Spindle deflection.
  • Poor chip discharge.

  Solutions:

  • Maintain optimal feed rate.
  • Adjust feed rate and rotation speed based on experience.
  • Replace cover material.
  • Inspect and verify CNC machine’s vacuum system.
  • Adjust retraction rate and drill speed.
  • Check and replace drill bit if needed.
  • Inspect and clean spindle and chuck.
  • Improve chip removal performance.

• White Circle Appearance on Hole Edge:

  Causes:

  • Thermal stress and mechanical force during drilling.
  • Thick glass cloth braided yarn.
  • Low-quality substrate material.
  • Excessive cutting depth.
  • Loose drill tip or inadequate fixation.
  • High number of PCB laminate layers.

  Solutions:

  • Check and replace or re-grind drill bit.
  • Use fine glass yarn for cloth weaving.
  • Upgrade to higher quality substrate material.
  • Verify correct feed amount.
  • Ensure proper drill bit shank diameter and clamp force.
  • Adjust according to laminate data and regulations.

Regular measurement and inspection are essential in PCB drilling production to maintain quality. Adhering to strict operational standards helps control quality failures and enhances product quality and production efficiency.