Blade Care

On Guard against Corrosion, Friction and Wear^™

Why should you do more than just keep a blade sharp?

Knives are unique.  So unique, in fact, they are sometimes tools, sometimes investments and always both.  Either way, they certainly are worth taking care of.  The best care is the preventative kind and Sentry Solutions' products are all about that.  It is best to start protecting your blades when they are new and clean.  Any knife, new or old, will benefit from simple care. 

A knife's care requirements relate directly to the materials used to make it.  The type of steel used in the blade determines the knife's corrosion resistance and wear characteristics.  The materials used in handles and sheaths, such as leather and wood, can not only limit the use of any knife, they also may need special care.  Considering that knives are one of the oldest tools known to man the possible choices of materials is endless.  Knives most likely got their start as broken seashells and sharpened rocks.  Now they have evolved to pieces of art and high tech marvels. 

There clearly are very good reasons for taking care of knives.  Let us address some specifics.  But first, keep in mind it is not within the scope of this page to cover all types of steel and all materials used for handles and sheaths.  There are just too many.

Blade Materials- The Real Enemy is Corrosion

For discussion purposes we will assume that blades are made from steel.  New materials such as Talonite^™ and ceramics generally require less care than steel.  Steel by definition is a mixture of iron and carbon, which can then be alloyed with numerous other elements to produce different properties.  So "Steel" actually encompasses more than 30 different types of steel, from O-1 to Vascowear^™.  Knife makers face the challenge of selecting the best type of steel to craft their blades from.  Their goal is to give their customers the right balance of properties; strength, durability, edge retention, wear and corrosion resistance.  Some types of steel are described as "stainless steel".  This does not mean "rust-free".  It actually means what is says, when the stainless steel is exposed to corrosive conditions it will stain less.  Very few types of metal will not corrode when exposed to the right conditions.  Unfortunately the "right conditions" are almost always present and steps must be taken to prevent corrosion of your knives.  This means the blade and any metal parts in the handle need to be protected.

What is corrosion?  Simply stated - it is the oxidation of metal.  Rust occurs when the iron in steel chemically converts to iron oxide.  We all know what corrosion of steel looks like, the metal turns red or dark colored.  When aluminum oxidizes it gets whitish, when copper oxidizes it turns green and so on.

What causes corrosion?  Air, and what is in the air, is the most common cause of corrosion.  This is why no matter what you do, your knives will always be faced with a potentially corrosive environment.  This can be in your pocket, glove box, tackle or toolbox, sheath and safe.  The only way of preventing the oxidation or corrosion of metal is to prevent the air from getting to it.

Protection against Corrosion

Knife makers face a huge decision when they select the materials to be used in the production of their knives.  They are looking for the right balance of performance, durability, cost and countless other factors.  When it comes to corrosion resistance there is a particular challenge.  Knife makers routinely choose steels with more carbon (ATS 34) to deliver blades with great edge holding and hard wearing properties.  However, the carbon actually decreases the corrosion resistance.  This means the blade might not need sharpening very frequently but will require regular rust protection.  The selection of steel is a science and can not be discussed here.  Every knife maker has an opinion and favorite steel.  Some of them may even have some secrets as to why they use a particular type of material for blades and others for handles. 

Increasingly knives are available with a growing number of finishes.  As with the selection of steel, finishes have different properties and different applications.  A good example is the use of Teflon^® finishes on dive knives and blades used by adventurers.  Teflon^®  is used to coat the blade (usually not the cutting edge) to protect it.  Some of these finishes last longer than others but all will wear off and so their protection needs to be monitored. 

The first rust inhibitor ever used was probably animal fat.  In fact, the folks who first used it probably didn't even know what they were doing.  They might have noticed that some of their crude blades did not change color (rust) as quickly as others after they skinned an animal.  They may also have noticed that some blades covered with blood, rusted more.  For hundreds of years fats, oils, and silicones have been used to prevent metal from rusting or corroding.  Oil is about the most common rust inhibitor used today.  Sentry Solutions is changing that. Anyone who has stored metal items in safes without real good climate control has found that gravity alone is enough to make oil's protection disappear. 

Oils and similar products do not bond to the metal surface.  They rely on viscosity and surface tension in order to "stick" to the metal.  What causes them to stick, also acts as a great magnet for dirt, dust and all kinds of debris.  Wax based products, sit on top of the metal and become brittle in the cold or turn to liquid in high heat.  This does not mean they do not work and should not be used.  It means you simply have to watch out for the conditions that cause them to fail. 

Sentry Solutions' TUF Line of Products, the TUF-CLOTH^®s and TUF-GLIDE^® ,are revolutionary dry film replacements for traditional protectants and lubricants.  What makes Sentry's product line revolutionary is "micro-bonding".  The active protectants and lubricants actually bond to the pores in a metal surface.  This means they are not subject to the effects of gravity, temperature, and will not be removed by the simple sheathing of a blade.  While these product benefits are important, probably the most important property Sentry's products have is they do not attract and hold dirt and debris.                                                                                                               

Protection against Friction and Wear

Knives and tools made of high tech materials may not require the care towards rust prevention but they do require lubrication.  This is very important, given that many knife companies sell the "smoothness" of their actions.  In order to maintain "smoothness" not only does the action require lubrication, it needs to be kept free of dirt and debris.  Cleaning the action of any mechanical device can be a major challenge.  The challenge is how to care for a knife without taking it apart.  Most manufacturers warn you not to void your warranty by disassembling their knives.  That means knife owners need a lubricant which will not attract and hold dirt or, for that matter, seal dirt in.  This fact alone is what differentiates some products from others.  Oils and similar substances by their nature will attract and hold dirt and are incapable of cleaning such debris off blades.  When Sentry looked at the problem of lubricating knives, guns and tools we saw that oils and silicones can actually create problems.  This is not because they do not work.  It is because they attract and hold dirt, are temperature sensitive and do not bond to metal surfaces. 

Sentry Solutions Products solve this problem.  Their wide operating temperature range and ability to work under all conditions is ensured by bonded protection.  Nothing thickens or becomes brittle in the cold and nothing will thin out from heat.  Bonded protection means longer lasting, even through cutting and use. 

The forces of friction found in knives are not extreme when compared with many mechanical devices.  While this is true, lubricating different types of knives and tools require different types of lubricants.  As with the selection of materials, you are looking for a balance.  Ideally you lubricate and protect with just the right amount.  The objective is to reduce friction and in so doing control the wear in your knives' moving parts.  Some knife mechanisms such as locks, require a certain amount of friction to work properly.  If the locking surfaces are over lubricated it may cause failure. 

Sentry is extreme when it comes to lubrication and corrosion protection. We make six products.  This sets us apart from most other companies who only offer one product to cover all bases.  It should be kept in mind that Sentry Solutions' Products were engineered for Special Operations Military personnel and Law Enforcement.  These folks carry knives, guns and all sorts of gear so the requirements for lubrication and protection are many.  In order to deliver high performance and reliability under all conditions we needed to develop some highly specialized products.  Each product designed to accomplish a specific task; the right tool for the job, whatever that might be. 

While knives and knife making have seen many changes and improvements over the years it is still up to each owner to ensure they get the best from their knives by taking a little time to care for them.

Take care of them and they will take care of you.