A 400-grit sanding disc is a fine abrasive tool designed for honing, surface smoothing, and scratch refinement on marble and other natural stone surfaces. It marks the transition from surface correction to finish development, making it a critical step for achieving uniform texture and preparing stone for high-clarity polishing stages.
Purpose & Function
The 400-grit disc refines the scratch pattern left by medium abrasives such as 200–320 grit, removing residual marks, light etching, and surface haze while producing a smooth, consistent honed finish. This step significantly improves surface uniformity and reduces the workload of higher-grit pads.
Typical Use Stage
This disc is commonly used in the mid-restoration and honing phase, before fine honing pads, sponge pads, or polishing systems.
Removes fine scratches and swirl marks
Smooths honed marble surfaces
Blends repair zones and transitions
Prepares stone for 800 grit, polishing pads, or pre-polish systems
Key Benefits of a 400-Grit Sanding Disc
Produces a smooth, uniform honed finish
Enhances surface consistency and color clarity
Reduces polishing time and improves final gloss
Controlled cutting with minimal risk of over-grinding
Suitable for wet or dry use (depending on disc design)
Effective on marble, limestone, terrazzo, and soft natural stone
Common Applications
Marble floor honing
Countertop and vanity refinement
Edge and profile finishing
Etch and light scratch removal
Surface prep before polishing or sealing