Grit Table / film / 3M Trizact
Product, maker figures and estimates
Structured abrasive, A-grade
3M's Trizact A-grade tracks the micron only at the fine end. For A5 to A16 the A-number tracks the micron and these are maker-published; at the coarse grades (A35 and up) the A-number runs ahead of the actual size, so those are our readings off the A-grade chart, estimated. No distribution is published, so each grade is a point.
Each grade below shows its size in microns, its spread (the published distribution, where a maker or standard gives one; most makers publish none), and where that size lands on the reference scale, a shared yardstick for reading grit numbers across makers.
~2500-3000 grit equivalent.
Often listed at ~5 micron, near-identical to A5; ~2500 grit.
A-number ~ micron holds; ~1500 grit equivalent.
~15 micron (note: NOT 16).
C-estimated: A-number begins to diverge from micron here; ~35 micron is the chart reading, ~600 grit.
C-estimated: A45 is ~40 micron (A-number > micron here).
C-estimated: A65 ~ 50 micron.
C-estimated: A80 ~ 60 micron.
C-estimated: A100 ~ 70 micron.
C-estimated: A160 ~ 120 micron.