Two core types of polishing buckets vary greatly in practical use. Standard buckets with central columns create uniform flow of magnetic pins, delivering balanced polishing for small regular parts. Column-free buckets offer larger internal space, ideal for long, irregular or oversized workpieces that cannot fit around central columns. Column-equipped barrels have better circulation efficiency for mass tiny products, while column-free ones avoid collision damage to elongated components and support more flexible placement of large workpieces during magnetic deburring.