A blade left in a pocket after cutting wet rope. A folder that sat in a humid drawer for too long. A prized piece that caught salt air during a beach trip. Rust forms on steel through small moments of neglect, and once it sets in, removing it properly requires extra effort. Our knives deserve better.
Everyday carry knives stay in working condition through mindful steel selection, protective maintenance products, and habits that keep moisture away. Attention to these details ensures your blade remains reliable.
In this guide, we cover corrosion basics, types of steel with strong resistance, maintenance products we offer, and daily habits for long-lasting performance.
Why Knives Rust in the First Place
Steel contains iron and carbon. When exposed to oxygen and water, iron rusts more quickly in humid or salty environments, or when moisture remains on a blade.
Corrosion resistance depends heavily on chromium. As we explain in our Analog Field Guide, chromium in steel helps form a protective surface layer. Without this layer, rust can develop and move deeper into the blade.
Molybdenum and nitrogen also help steel resist pitting. Chromium, molybdenum, and nitrogen can form carbides or nitrides during forging, which limits the amount present at the surface. As a result, both composition and heat treatment influence corrosion resistance.
Stainless steel resists corrosion better than carbon steel, but rust can still develop if exposed to moisture or salt for long periods. Keeping this in mind leads to better care.
Choosing Steel That Fights Corrosion
If a blade dulls quickly or develops rust after a few weeks, check the steel. As noted in our Analog Field Guide, the choice of steel affects sharpness retention, ease of sharpening, and corrosion resistance.
Knife steel comes with trade-offs among edge retention, corrosion resistance, toughness, and ease of sharpening. No steel excels at all four. Your environment and maintenance preferences should guide your selection.
CPM S35VN and S30V
CPM S35VN offers edge retention and corrosion resistance, and is easy to sharpen with a basic stone. S30V, its predecessor, performs similarly. Both steels are produced via Crucible Industries’ powder metallurgy process, which yields a consistent grain structure. S35VN includes added niobium, improving toughness.
MagnaCut
Designed by Dr. Larrin Thomas, MagnaCut balances toughness and corrosion resistance. It measures 62-64 HRC on the Rockwell scale. Its corrosion resistance exceeds S45VN in salt-spray tests. MagnaCut brings strong edge strength and corrosion protection.
M390, CPM 20CV, and CTS-204P
These steels include high chromium for corrosion resistance and vanadium carbides for wear resistance. They take more effort to sharpen but require less frequent sharpening than most others.
How Corrosion Damages More Than Appearance
Corrosion on knife steels appears as rust, patina, and staining. Rust dulls the edge, causes pitting, and may damage structural integrity over time.
Carbon steel forms patina naturally. This discoloration can help protect the blade by creating a stable oxide layer. Light patina is normal. Heavy rust, however, damages the metal and reduces performance.
Products We Stand Behind
KPL Original Knife Oil
We carry the KPL Original Knife Oil in an exclusive Urban EDC Seigaiha edition, featuring the traditional Japanese wave motif.
This 15 WT, fully synthetic oil is designed as an all-in-one lubrication solution for knives that require long-lasting, smooth operation. What sets it apart is its contaminant encapsulation technology. Dirt, metal particles, and grit stay suspended in the oil rather than grinding against your knife's moving parts. KPL cleans your pivot as you use it.
The technical specifications explain why it excels at rust prevention. KPL includes high-pressure film stabilizers to prevent metal-on-metal contact under stress, corrosion inhibitors to prevent rust and oxidation, and wickability modifiers to help the oil penetrate tight spaces instantly.
We recommend KPL for all moving parts of folding knives, flipper-deployed mechanisms, detent tracks, bearings, and as a rust-preventive coating on blades.
All American Maker x Urban EDC Blade Wax
We also carry Blade Wax from All American Maker in Jamestown, NY. This USA-made product is crafted from beeswax, organic hemp seed butter, and organic raw flaxseed oil. It forms a protective layer that repels moisture and helps guard against rust, even in humid environments. Applied to blades and tools, it reduces friction for smoother cuts.
Daily Habits That Prevent Rust
Steel selection and lubrication matter, but daily habits most affect rust prevention. Our founder, Yong-Soo Chung, emphasizes that edge retention and maintenance are essential. Applying excessive pressure to a dull knife is unsafe.
Keep It Clean
Dust, debris, dirt, and sweat build up with regular use. This buildup can jam mechanisms and leave residue on the blade. Moisture causes rust, degrades oil in ball-bearing systems, and accelerates wear.
After using a knife, wipe the blade clean. If it was used on wet materials or in humid conditions, dry the blade thoroughly before storing.
Keep It Dry
If a knife gets wet, dry it right away. Pay attention to the pivot area on folders, where moisture can collect. Opening and closing the blade a few times helps release trapped water before wiping down.
Keep It Lubricated
A thin layer of oil protects the blade from moisture. For folders, oil the pivot, detent track, and other moving parts. KPL or similar knife oil is effective. Apply oil regularly, especially after cleaning or exposure to water.
Store It Properly
When your knife is not in use, store it in a dry place away from extreme temperatures and humidity. Adding a few desiccant bags to your knife case helps keep ambient moisture in check.
Avoid storing fixed blades in leather sheaths for extended periods. Leather can trap moisture, which may corrode the blade. If using a leather sheath, remove the knife when not carrying it and store the blade separately in a dry location.
Carbon Steel Requires Extra Attention
Carbon steel blades are more susceptible to rust than stainless steel and require more frequent maintenance.
Keep carbon steel clean and dry. Apply a thin coat of food-grade mineral oil or knife oil after each use. Over time, carbon steel develops a natural patina; mild discoloration is normal and can help protect the blade.
If you carry a carbon steel blade in humid conditions or expose it to salt air, check it more frequently. Wipe it down, dry it, and reapply oil. The extra effort pays off in a blade that lasts.
Matching Your Blade to Your Environment
Humidity, cardboard, plastic, and occasional contact with metal or concrete can affect knife performance. Some steels for daily carry require less frequent maintenance in these environments.
If you live in a coastal city with salt air, prioritize corrosion resistance. MagnaCut or high-chromium steels like M390 make sense. If you are in a dry climate and use your knife heavily, edge retention and toughness may matter more.
Match your steel to your use and conditions. The right choice means sharpening and maintenance are needed less often.
Taking Care of What You Carry
A knife should work every time. Consistent care extends its performance.
Choose the right steel, use proper maintenance products, and keep moisture away for a longer-lasting knife.
We carry a wide selection of knives built to perform and products designed for durability. Regular cleaning, drying, oiling, and proper storage all help your knife last longer.
