After the mold has cooled following welding, what is the recommended handling of the mold interior?

• A. Replace the mold with a new one.
• B. Clean the inside of the mold with a soft bristle brush or soft cotton cloth.
• C. Seal the mold and store it upright.
• D. Apply a protective coat to the exterior only.

Answer: (B)

After the mold has cooled, keep the interior clean to prevent any residues from affecting the next weld. Gently removing slag, scale, and flux with a soft bristle brush or a soft cotton cloth is ideal because it removes contaminants without scratching or damaging the mold surface. A clean interior helps maintain proper heat transfer, surface finish, and dimensional accuracy in future casts. Replacing the mold every time is unnecessary and wasteful; a reusable mold remains valuable as long as its interior is kept clean. Sealing and storing the mold upright doesn’t remove interior contaminants and could trap moisture or debris, while coating only the exterior leaves the inside dirty and can interfere with the next pour.