Blasting Media Grit Size & Mesh Size Guide: How to Read & Convert

Why Particle Sizing Matters

Grit size is the parameter that most directly controls surface profile depth in abrasive blasting — and surface profile depth is one of the most critically specified variables in industrial coating application and shot peening. Selecting the wrong grit size produces a profile either too shallow for adequate coating adhesion, or unnecessarily deep — wasting abrasive and creating coating thickness variation that compromises service life.

Despite being critically important, abrasive particle sizing is one of the most frequently misunderstood aspects of blasting media specification. Different industries, regions, and media types use different sizing standards — FEPA, ANSI, US Mesh, JIS, SAE — that are not directly interchangeable. Specifying “60 grit” without naming the standard invites the wrong media: FEPA F60 and US Mesh 60 are different particle sizes, and using one where the other is intended will produce incorrect results.

This guide resolves that ambiguity by covering all major standards, providing full conversion tables, and mapping grit sizes to the surface profiles and applications they produce. For broader context on media selection beyond sizing, see: Abrasive Blasting Media Complete Guide.

How Abrasive Particle Sizing Works

Abrasive particle size is determined by sieve analysis — passing the material through a series of standardized wire mesh screens with precisely defined opening sizes. Particles that pass through a given sieve but are retained on the next finer sieve are classified as belonging to that size fraction.

The fundamental unit is the sieve opening size in microns (µm), the actual physical dimension of particles in a given fraction. All sizing standards ultimately reference micron dimensions, even though they label products differently.

The single most important principle to remember: higher grit or mesh number = smaller particles = finer finish and shallower profile. Lower number = larger particles = coarser, deeper profile. This inverse relationship is consistent across all standards, even though the numbers themselves differ.

Major Sizing Standards Explained

FEPA (Federation of European Producers of Abrasives) — F-Series

FEPA is the primary standard for synthetic abrasives — aluminum oxide and silicon carbide — in Europe and internationally. The F-series (free abrasive grain) applies to blasting, lapping, and polishing applications. FEPA F-grit sizes run from F4 (very coarse, ~4,000 µm) through F1200 (ultra-fine, ~4 µm). Jiangsu Henglihong Technology uses FEPA for all aluminum oxide and silicon carbide product specifications.

ANSI (American National Standards Institute) — B74.12

ANSI B74.12 defines abrasive grain sizes for the US market. ANSI grade designations (ANSI 36, 60, 80, etc.) roughly correspond to FEPA F-series numbers in nominal particle size, but particle size distribution requirements differ slightly. For most industrial applications the two are functionally interchangeable at the same grade number, but strict compliance specifications require confirming which standard governs.

US Mesh (ASTM E11 / Tyler Mesh)

US mesh sizing is used primarily for glass beads, garnet, walnut shell, corn cob, and other non-synthetic media. The mesh number equals openings per linear inch in the sieve screen. Blasting applications use US mesh from approximately 6 (coarse, ~3,360 µm) through 400 (ultra-fine, ~37 µm). Garnet is commonly specified in double-fraction notation (e.g., 30/60 — retained on US 30, passing US 60 — equivalent to 250–600 µm particle range).

SAE (Society of Automotive Engineers)

SAE standards govern steel shot and steel grit sizing. Steel shot grades are designated S-110 through S-780; steel grit grades G-10 through G-120. SAE J827 (shot) and SAE J1993 (grit) define each grade’s size distribution. ISO equivalents are ISO 11124-2 (steel grit) and ISO 11124-3 (steel shot).

JIS (Japanese Industrial Standard) — R6001

JIS R6001 is closely aligned with FEPA F-series for most commercial blasting grades. JIS uses the same grade designation numbers as FEPA at common sizes (JIS #36 ≈ FEPA F36). For cross-border procurement involving Japanese manufacturers or specifications, JIS and FEPA are largely interchangeable at equivalent grade numbers.

FEPA Grit Size Chart — Aluminum Oxide & Silicon Carbide

US Mesh Size Chart — Glass Bead & Garnet

SAE Size Chart — Steel Shot & Steel Grit

Cross-Standard Conversion Table

The table below provides approximate cross-standard equivalents based on median particle size (D50). These are approximations — the actual particle size distribution requirements defined by each standard differ, so always consult the full standard document for critical applications.

Grit Size vs Surface Profile Depth

The table below maps grit sizes to achievable surface profiles for the three most common industrial blasting media. Values represent typical results at 60–90 PSI, 15–30 cm standoff distance, and 75–90° impingement angle on carbon steel. Actual profiles vary with pressure, nozzle type, standoff, angle, and substrate hardness — always measure actual profiles with replica tape or a contact profilometer before committing to production blasting parameters.

Application-Based Grit Size Selection Guide

Use this table to directly look up the recommended grit size for common industrial applications. For applications not listed, use the profile data tables above to identify the grit size that achieves the required Ra or Rz, then confirm with a test blast before production.

For media-specific grit size guidance, refer to the individual media type guides: Aluminum Oxide Grit Sizes · Silicon Carbide Grit Sizes · Glass Bead Mesh Sizes · Steel Shot & Grit SAE Sizes.

Frequently Asked Questions