The knife sharpening handbook
A sharp knife starts with the right angle
Which angle, which grit and which stone: how to set up a whetstone, raise a burr, strop the edge, and what to change when the knife is still dull after sharpening.
How high do I hold the spine?
Open the full angle calculator →Blade and angle
degrees
Common angles, per side
Spine height
11.6 mm
0.46 in, nearest 15/32 in
above the stone
Edge angle
15 per side = 30 inclusive
degrees; inclusive is both sides added
Geometry only: spine height = blade width x sine of the angle per side. It tells you where to hold the knife, not which angle is right for it. Where the knife maker states an angle, the maker's figure wins.
Still dull after sharpening?
Start from the symptom: no burr, a dished or glazed stone, a strop gone black.
- Knife is still dull after sharpeningKnife still dull after 20 minutes on a whetstone? A symptom table with 8 causes and fixes, from an angle that is too low to a burr that never came off.
- Whetstone is dished or unevenFlatten a dished whetstone with a pencil grid and one of 3 tools: a flattening stone, a diamond lapping plate or 220 grit wet/dry sandpaper on glass.
- Stone is grey, glazed and no longer cutsClean a grey, glazed sharpening stone by type: water, oil, diamond or ceramic. What to use, what never to use, and the sign that the stone needs flattening.
- Strop is black, glazed and stopped workingClean a black, glazed leather strop: wipe, scrape, sand lightly and reload a thin coat. When to reload compound, what never to use and what wears a strop out.
- Stone is thin, dished, cracked or slowNo maker prints a lifespan in years for water or oil stones. The signs a stone is finished, what to flatten or clean instead, and DMT's figures for diamond.
The process, step by step
Six steps from a dull edge to a stropped one. Each step has one signal that tells you it is done, and it is never a stroke count.
- ·Choose your stonesWater stone, diamond plate or oil stone, and which grits are worth buying first.2 notes · 11 gear guides
- 1Find the anglePick the angle per side for your knife and turn it into a spine height you can see.6 notes · 6 gear guides
- 2Set up the stoneSoak or splash, a flat face and a base that does not slide on the counter.3 notes · 3 gear guides
- 3Raise a burrWork one side at a steady angle until a burr runs along the whole edge.1 note · 0 gear guides
- 4Coarse to fineMove up through the grits: each finer stone removes the scratches of the one before.1 note · 1 gear guide
- 5Strop the edgeSpine-first passes on leather clear the last of the burr and polish the apex.6 notes · 2 gear guides
- 6Hone and maintainKeep the edge with a rod or a strop, and keep stones clean, flat and dry.4 notes · 4 gear guides
Charts to keep by the stone
Angles by knife type and by brand, grits in microns, and what a strop adds after the last stone.
- Whetstone Grit Progression: Which Grit to Use First and NextPick the state of the edge and the stones you own, get the order to use them in and where to stop.Tool
- Sharpening Stone Grit Chart: Whetstone, Diamond and Oil Stone GritsPrintable grit chart: Japanese (JIS) water stone grits 240 to 8000 in microns, beside DMT diamond mesh and colors and Arkansas oil stone grades.Printable
- What Grit Is a Leather Strop? Bare Leather and Compound ChartBare leather has no grit rating. Chart of strop compounds by the micron size the maker labels, 7 down to 0.5, beside the matching water stone grit.Printable
- Factory Sharpening Angles by Knife BrandFactory sharpening angles for 9 knife brands, each taken from the maker's own page: Wusthof 14 per side, Shun 16, Benchmade 30 to 35 inclusive.Printable
- Knife Sharpening Angle Chart: Kitchen, Pocket and Outdoor KnivesKnife sharpening angle chart for 11 knife types, from 10 to over 30 degrees, with per side and inclusive figures side by side and the basis for each.Printable
Gear, one item at a time
Narrow guides that compare one kind of stone, strop or accessory by what the listings state.
- Best Cheap Knife Sharpeners Under $15 That Actually Work
- Best King Whetstones: Grits, Sizes and Which One to Buy
- Best Shapton Sharpening Stones: Kuromaku vs Glass Stone
- Best Knife Sharpening Wheels for a Bench Grinder
- Best Sharpening Stones and Sharpeners for Garden Tools
- Best Scissor Sharpeners and Sharpening Stones for Scissors
- Best Knife Sharpener for Fillet Knives: Boat, Dock and Kitchen
- Best Knife Sharpener for Serrated Knives: Tapered Rods and Slots
- Best Chef'sChoice Knife Sharpener: Electric, Hybrid and Manual Models
- Best Lansky Knife Sharpeners: Clamp Systems, Crock Sticks and Pocket Tools
- Best Rolling Knife Sharpeners: Tumbler, HORL and Cheaper Alternatives
- Best Manual Knife Sharpeners: Pull-Through and Adjustable Picks
- Best Whetstone Sets: Multi-Grit Kits With Holder and Flattener
- Best Whetstones for Japanese Knives: Which Grits and Which Stones
- Best Whetstone for Beginners: One Stone That Covers Most Knives
- Best Whetstone Flattening Stones and Diamond Lapping Plates