Why No-Go Gauge Fails After 1000+ Holes for M3 Extrusion Tapping on Die-Cast Aluminum

1. Characteristics of Die-Cast Aluminum

• Soft material with a low melting point
• Prone to heat generation and chip adhesion (galling) during machining

2. Features of Extrusion Taps in Tapping

• Torque is 3-4 times higher than that of cutting taps
• Heats up faster during machining, leading to more severe chip adhesion
• Easy to cause thread damage (thread galling) due to chip adhesion
  

  

3. Core Reason for No-Go Gauge Failure

• Excessive heat of the tap causes aluminum material to stick to the tap surface
• Adhered aluminum deforms the internal thread and causes burrs
• Result in thread size deviation, leading to No-Go gauge failure (No-Go gauge can pass through)
  

  

4. Severe Consequences if Not Improved

• Serious thread damage (galling) and unqualified precision
• Excessive torque may directly break the tap

5. Improvement Solutions

• Choose extrusion taps with short thread and relief groove (special for die-cast aluminum)
• Add oil grooves on the tap to enhance chip removal and heat dissipation
• Strengthen cooling and lubrication to avoid tap overheating
• Reduce aluminum adhesion and ensure internal thread precision
  

  

6. Normal Service Life After Improvement

• After adopting the above solutions, the service life of the extrusion tap for die-cast aluminum can reach 10,000+ holes