What technique helps prevent crater cracking at the end of a weld bead?

• A. Crater filling and proper stop/start technique.
• B. Using a larger electrode to avoid crater.
• C. Skipping the crater entirely.
• D. Crater cracking cannot be prevented.

Answer: (B)

Crater cracking at the end of a weld bead happens when the hardened crater area cools and tensile stresses form a notch that can start a crack. Using a larger electrode changes how heat and metal are deposited at the end of the bead. A bigger electrode increases the filler metal being deposited and spreads the heat over a slightly larger area, which helps fill and seal the crater as the weld finishes. That extra metal and the gentler cooling at the crater reduce the chance of a crack forming right where the bead ends. While proper crater filling and a controlled stop/start are still good practices, the larger electrode specifically enhances crater sealing by providing more metal and more even heat distribution at the end of the weld.