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AhaBulb: Stuff Everyone Should Know · ahabulb.com/weld-porosity-contamination

Which base metal condition can lead to porosity in a weld?

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  1. Oil, grease, mill scale, rust or moisture
  2. Clean, dry, freshly ground metal
  3. Metal that is slightly magnetic

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References

  1. Hobart Brothers, MIG Troubleshooting for Metal-Cored and Solid Wire www.hobartbrothers.com/resources/technical-articles/mig-troubleshooting-for-metal-cored-and-solid-wire Checked 2026-10-10.

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