Interior curves must be sanded by using which tool?

• A. Belt Sander
• B. Spindle Sander
• C. Disk Sander
• D. Hand Sanding

Answer: (B)

Sanding interior curves is best done with a spindle sander because its cylindrical drum rotates and can be fed along the inside of curved profiles, letting you follow concave radii and reach tight curves with a consistent contact area. Belt sanders and disk sanders have flat or broad contact surfaces that aren’t well suited for inside corners or narrow radii, making it easy to round off or miss the curve. Hand sanding can do the job, but it’s hard to maintain a uniform radius and takes much longer. The spindle sander provides the controlled, curved contact needed to cleanly sand interior curves.