Cratex Grit Guide for Knife Makers
Cratex uses a simple color-coding system: Coarse (brown), Medium (green), Fine (blue), Extra-Fine (white). But knowing the colors doesn't tell you when to use each one.
This guide maps Cratex grits to your knife finishing workflow so you know exactly which wheel or point to reach for at each stage.
The Color System
| Color | Grit Level | Equivalent Belt Grit | Primary Use |
|---|---|---|---|
| Brown | Coarse | ~80-120 grit | Aggressive scratch removal |
| Green | Medium | ~180-220 grit | General finishing |
| Blue | Fine | ~320-400 grit | Pre-polish prep |
| White | Extra-Fine | ~600+ grit | Final prep before compound |
Matching Cratex to Your Belt Progression
The key rule: Start your Cratex work at the grit level that matches your last belt.
After 120-Grit Belt
Start with Coarse (brown). You have deep scratches that need aggressive removal before refinement.
After 220-Grit Belt
Start with Medium (green). This is the most common starting point for knife makers. Your belt scratches are visible but not deep.
After 400-Grit Belt
Start with Fine (blue). You're refining, not removing. Light scratch pattern cleanup.
After 600+ Grit Belt
Start with Extra-Fine (white). You're bridging to compound or achieving a fine satin finish.
The Complete Progression
Here's a full finishing workflow for a high-end knife, starting after your 220-grit belt work:
- Medium (green) Cratex wheels — Remove belt scratches from blade flats
- Medium (green) Cratex cones — Clean up plunge lines and transitions
- Fine (blue) Cratex wheels — Refine blade flats
- Fine (blue) Cratex cones — Refine plunge lines
- Extra-Fine (white) Cratex wheels — Final machine prep
- Extra-Fine (white) Cratex cones — Final plunge line work
- Hand sand 800-1000 grit — Final scratch direction
- Polishing compound — Mirror finish (if desired)
For a satin finish, stop at Extra-Fine and hand sand to your desired scratch pattern.
When to Skip Grits
Short answer: Don't.
Each grit removes the scratches from the previous grit. Skip Medium and go straight from Coarse to Fine? Those deep coarse scratches will show through your fine work. You'll spend more time chasing them than you saved by skipping.
The only time you can skip is when your starting surface is already finer than the grit you'd skip. If you're at 400-grit belt finish, you can skip Coarse and Medium entirely — start at Fine.
Special Cases
Damascus Pre-Etch
Before acid etching, you want a clean, consistent surface. Work through to Extra-Fine (white), then lightly hand sand to 600+ grit in one direction. The etch will reveal the pattern against this consistent background.
Mirror Polish
After Extra-Fine, consider the MX polishing wheels — they're even finer than white. Then move to polishing compound on a buffer. Every previous scratch must be eliminated for a true mirror.
Hand-Rubbed Satin
Work to Fine or Extra-Fine with wheels, then hand sand in one direction with a Cratex stick or sandpaper to establish your final scratch pattern. The directional scratches are the satin finish.
Recommended Starting Kits
- Knife Maker Starter Kit — All grits in the most-used shapes. Figure out what you reach for.
- Mini Wheel Kit No. 107 — Wheels in all grits for blade flat work.
- Cones (Box of 100) — Once you know which grit you use most for plunge lines, buy in bulk.
The Bottom Line
Cratex grits work just like sandpaper grits — start where your current finish is, work through the progression, don't skip steps. The color system makes it easy to grab the right wheel mid-project.
Brown → Green → Blue → White. Coarse to fine. Scratches disappear with each step.