Abrasives
Grinding and Sharpening CPM S30V: Belt Recommendations & Technique
CPM S30V is one of the more demanding steels in this database to grind, sitting alongside CPM 20CV and CPM M4 near the top of the “hardest to work” list…
Knife steel
CPM S30V knife steel
A landmark premium stainless steel developed for knifemaking, prized for top-tier edge retention and good corrosion resistance, though tougher to grind and slightly less tough than its successor, S35VN.
Also known as
At a glance
How CPM S30V behaves
The four meters are relative to the rest of the database. Composition is the published nominal analysis, not a mill certificate for your bar.
Working properties
- Toughness
- 3
- Edge retention
- 5
- Corrosion resistance
- 4
- Ease of grinding
- 2
- Composition
- Best uses
The steel behind many legendary premium production folders, still a strong choice for EDC knives where long edge retention is the top priority. Browse more entries in the Knife Steel Database, and see the Heat Treating Guide for the full stage-by-stage process.
- Sources
At the bench
What each property means for this steel
Open the property you are worried about. Every note is written for the blade in your hand, not for a spec sheet.
Toughness
The weakest point of an otherwise excellent steel; a heavier vanadium carbide load than S35VN makes it more prone to chipping, which is the main reason Crucible developed S35VN as a tougher successor.
Edge retention
Rated around 149% CATRA edge retention versus 440C, among the best in its class and the main reason it remained the benchmark premium stainless steel for years.
Corrosion resistance
Good stainless performance from 14% chromium, comparable to S35VN and suitable for everyday-carry and outdoor use.
Grinding and machinability
Notably harder to grind than S35VN due to its higher vanadium carbide content; expect faster belt wear and slower stock removal.
The full reference
More on CPM S30V
CPM S30V was developed by Crucible Industries with knifemaker Chris Reeve specifically for the cutlery market, and it became the benchmark premium stainless steel for over a decade. Its vanadium-rich chemistry and fine powder-metallurgy grain give it exceptional edge retention, though it can run tougher to grind and slightly less tough than the newer steels it inspired, like S35VN.
CPM S30V FAQ
What hardness does CPM S30V reach?
Most knives run in the low-to-mid 60s Rc. See the heat treat details further up this page for the full recipe.
Is CPM S30V hard to sharpen?
Yes, it is one of the more demanding steels in this database to sharpen due to its heavy vanadium carbide content. It can be sharpened effectively on the belt grinder itself with soft-backed belts and a felt polishing wheel, or off the machine with diamond abrasives. See the full grinding and sharpening guide.
Does CPM S30V rust?
It offers good, dependable stainless corrosion resistance from its 14% chromium content, suitable for everyday-carry and outdoor use.
How does CPM S30V compare to CPM S35VN or CPM 20CV?
S30V holds a slight edge-retention advantage over S35VN but is tougher to grind, and offers slightly less corrosion resistance than CPM 20CV at essentially tied edge retention. See the full breakdowns: CPM S30V vs CPM S35VN and CPM 20CV vs CPM S30V.
Head to head
Compare steel data for CPM S30V
Every matchup CPM S30V appears in, dimension by dimension.
Keep reading
Guides that use this steel
MetallurgyWhat Alloying Elements Do: Carbon, Chromium, Vanadium & More
Every knife steel is iron plus a specific recipe of other elements, and each of those elements pulls the steel’s behavior in a particular direction…
MetallurgyCarbide Size and Sharpening: Why Some Steels Feel Different
Two steels with similar hardness numbers can feel completely different under a sharpening stone, one glides along smoothly, another feels like it’s…
Same bench
Grind CPM S30V on a machine that holds still
Whatever the steel, the grind is only as flat as the platen behind it. I machine the parts, hand-assemble and test Torus grinders in Sterling, Illinois.
Nova 2×72 Aluminum Belt Grinder
Current dual-axis platform with a fiber-laser-cut 6061 chassis and single-knob tracking.
Starts at$1,295
Nebula 2×72 Steel Belt Grinder
Current dual-axis platform with a steel chassis, more mass and less vibration.
Starts at$1,295
Torus 2×72 Classic Aluminum Belt Grinder
Prior-design aluminum chassis, 90-degree tilt and 1.5-inch tooling arms.
Starts at$995
One-man shop
Thinking about CPM S30V?
Tell me what the blade is for and how you heat treat. I will tell you whether this is the steel I would use, and what I would use instead.