Knife Care and Maintenance

Caring for your knife is just as important as choosing the right type of knife. I'd choose a low quality knife that's been well cared for over a top quality blade that's been abused any day of the week.

But what goes into caring for a knife? It's more than just sharpening your blade once every six months. In this article I'll detail the steps required to care for and maintain your knives.


Water Damage

Corrosion is the biggest danger to knives, especially those that sit without being used for a long time. Even stainless steels will rust if exposed to enough moisture for a long enough period of time.

The best practice is to keep your knife dry. It seems obvious, but many people overlook this. Some think that a stainless steel blade can sit in water with no issue. Others simply think that rust will take hours to form and simply forget about their knives.

A rusty knife is useless. Photo by Flickr user natamagat

Always dry off your knife once you're done using it. Wipe it off on your pants if you need to but always make sure you've removed all water from the cutting edge. Serrated blades are notorious for trapping moisture hidden between the serrations which is one reason why I dislike them.

Blood is a serious concern. Liquid blood is mostly water, but once it dries it is much harder to remove and is still corrosive, especially to high carbon steels.

Never let any moisture get into the sheath. The last thing you want to do us place a blade into a clammy scabbard where it can rust without you seeing it. A leather sheath will breath and eventually should dry out but a plastic one will be a water-tight rust factory.

Sharpening

Always maintain as sharp an edge as the blade requires. You won't want to put a razor edge on a chopping blade (too thin an edge will lead to the blade chipping), but it should still be sharp enough to both carve wood and skin an animal, especially if this is your only knife. There's a reason why most experienced hunters carry a skinning knife as well as a good bush knife. A skinning knife will usually be thinner (and hence sharper) than a survival knife. Remember, a survival knife is a jack of all trades but master if none.

A knife blade that's been damaged
by pulling staples. Image by Flickr
user Thirteen Of Clubs

A dull knife is just dangerous. You have to work harder at what you're doing, which not only expends more energy but also increases your chances of injury.

One important thing to note is that if you use oil as lubricant for your sharpening stone, remove as much as you can from the blade before you polite it in its sheath. A very thin coat of oil on a blade is fine but oil can trap water in the sheath. Oil takes a lot longer than moisture to leech out of leather (it may never come out) and if it traps moisture in there with it then you've hit a clammy rust factory.

If you have a very dull knife, NEVER use a bench grinder to touch up the edge. The grinder will rotate at a high enough speed to ruin the temper of the cutting edge, meaning that you'll be ending with soft metal instead of tempered steel. At the very most, you can use a slow grinder that is water lubricated but only use this as a last resort.

Use the Correct Lubrication.

Many stones are designed to use water as a lubricant during sharpening. Others use oil. You should always use a low viscosity oil, such as mineral oil, and never use motor oil, which can contain particulates that damage your knife.

Using the Right Blade for the Right Job.

Using a knife as an axe can often
break it at the hilt. Using a
baton on the knife will reduce
stress and prevent this. Photo by
Julie Vazquez

I've seen plenty of people destroy knives by using them in a manner in which they weren't designed. Stressing a knife that's not designed to live up to it will damage the knife, sometimes irreparably. To be specific, a thin fillet knife being used to carve or chop wood. It happens more often than one would think. A thin knife simply won't hold up to the same stress to which a thicker knife is designed.

Long Term Storage

If you plan to store your knife for an extended period of time without being used, it's recommended to store it out of its sheath. As noted above, a sheath can trap in moisture, and even a small amount over a long enough period of time can damage a knife. If you don't plan on using a knife for a very long time, store it instead in a scabbard made of thick paper or cardboard, which is open at the tip. This will allow air to flow through that will dry out any moisture that gets in. This will work for all but the most humid climates.