The tool used to sand interior curved surfaces is which?

• A. Belt Sander
• B. Disk Sander
• C. Random Orbit Sander
• D. Spindle Sander

Answer: (D)

When you need to sand interior curved surfaces, you want a tool that can follow tight radii and fit into corners. A spindle sander does this best because it uses a small cylindrical drum that rotates and can be matched to different radii with various drum sizes and sanding sleeves. This setup allows you to run the drum along the inside curve with consistent contact, producing a smooth, uniform finish without rounding off sharp inside edges.

Belt sanders rely on wide belts and are ideal for flat, broad surfaces, not for navigating curves. Disk sanders have a flat sanding face and are also suited to flat work or edges, making interior radii difficult. Random orbit sanders are versatile for general finishing but their round pad tends to skim over tight curves and corners, making it hard to achieve uniform results inside curved cavities.

So, for sanding interior curved surfaces, the spindle sander is the best choice. Remember to choose the drum size that matches the curve and use the right grit for the final finish.