You Can’t Sharpen Iron with a Marshmallow

Most people have heard the phrase “iron sharpens iron” at some point. But have you thought about the real impact of the principle?

welder at work

It’s from Proverbs 27:17 and in full it says “as iron sharpens iron, so one person sharpens another”.

For many people in Christian circles and otherwise, this is a nicety that they use to encourage meeting together regularly.

For others, the phrase might encourage you to ensure that the people around you are constantly challenging you, rather than dragging you down.

Unfortunately for many, very little sharpening takes place despite their hopes.

But then, a lot of people have never tried to sharpen something made of iron before — and so they don’t have a full appreciation for what the phrase is really getting at. They might not be prepared to either apply the process or have it applied to them.

Sparks and Heat

Sharpness is simply the meeting of two geometric planes at an angle — the closer the planes get to each other, the sharper the object.

When something is made of metal, the only way you can make it sharp is to progressively take pieces of metal off the object from each of the two planes, until they meet as closely together as you can make them.

For something as hard as iron, the process of gradually removing metal from it is not always pleasant. In fact, it is usually accompanied by sparks, heat, or a bit of both.

If you’re not prepared to give the blade the necessary treatment — it simply won’t get sharp.

You Start Rough…

For a particularly dull blade, the process of sharpening at first is quite brutal (at least — so far as the blade is concerned).

You have to get the blade in a position where it can actually be honed, and that necessarily involves removing more metal.

You might have to remove rust or reshape the bevel of the blade.

Perhaps previous mistreatment has left the blade with damage and nicks that need to be taken out before it can function well.

It’s only after the initial hard work that you can start to even begin the process of sharpening properly. Over time, the sharpening process becomes finer. You’ve gone from roughing out the shape and angles to really getting the blade sharp.

This results in a blade with a high polish.

But if you polish the blade before you have prepared it, it will look pretty but be useless for its job.

A blade that has been through the entire process cuts better, works better, and serves its purpose better.

You Need the Right Equipment

You can’t sharpen iron with a marshmallow. It’s too soft. But not all blades need the same treatment.

A chisel blade made of D2 steel is hard to sharpen. It requires particular stones. A2 steel is different.

The Japanese laminate their blades, so that there is a “soft” metal to ease the sharpening process, while the cutting edge is made of a very hard, but highly brittle, type of metal.

Each different type of tool requires a different technique as well.

So before you start thinking that all tools can be sharpened the same way, just remember that sharpening the wrong way, with the wrong things, can blunt the tool even worse than it started.

Or ruin the tool.

So be careful.

Blades in Use Require Constant Honing

The woodworker in me would be delighted if my blades would stay sharp forever. But they don’t.

The blades in our clever metaphor here are exactly the same.

But the more regularly they are honed and kept in prime condition, the less often they require a complete resharpen.

We take off tiny, invisible pieces of metal from the blade each honing — to ensure that it’s as close to perfect as we can get it with our human efforts.

It would be easy to try and keep our blades sharp by sticking them in a drawer. But what’s the point of a sharp tool that doesn’t get used?

Be Prepared

If you want to sharpen and be sharpened — then be prepared for sparks and heat, pain and confrontation, and a bunch of hard work.

But provided the process is in the hands of a master craftsman, the result will be a fine blade.


Originally published at Chris Hargreaves.