Leather Stropping & Compounds

Keeping our tools sharp helps ensure safe and accurate cutting through material. I’ll share what I have learned along the way about leather strops.

A strop is a narrow strip of leather used to restore the cutting edge of a knife or crafting tool. Typically, this is enhanced with the use of honing compounds or diamond sprays. Strops are available in many hung, hand-held, and mounted configurations to serve the user’s preferences and needs.

Sharpening a blade is all a lead up to the “strop”. Let’s take a look at what works for a strop, the different configurations they are available in, and what can be substituted for a strop in a pinch.

What Is a Leather Strop?

A strop in its most basic form is a flat surface capable of holding a stropping compound. Newspapers and magazines have been used in a pinch as well as denim, cotton and felt fabrics. Generally, a strop is usually a strip of leather that is used to remove the “burr” from the cutting edge of a freshly sharpened blade.

Leather strops come in a variety of styles and colors. They are generally made from vegetable tanned leather with a few popular makers offering an oil tanned leather option.

When a blade of any kind has just been freshly sharpened, a burr is formed. It is the microscopic material that remains and curls up along the new edge. Drawing the blade backwards across a strop several times on both sides, removes that burr leaving a clean, crisp, polished cutting edge.

Therefore, stropping is the final step in honing a blade’s edge down to a microscopic level. This is accomplished using stropping compounds, pastes, or sprays to re-sharpen a dulled blade.

Stropping the edge of a straight razor, kitchen knife, hunting knife, woodworking chisel, or other crafting tool(s), is an exercise in geometry, metallurgy, hand-eye coordination, and a lesson in controlling both pressure and speed inorder to achieve the best possible outcome of the sharpening process.

Leather Strop

What to Look For in a Leather Strop

There are various elements to consider when determining which type of leather strop will be most beneficial for one’s working style, and types of blades being sharpened. Let’s take a look at the key factors to consider when looking for a really effective strop. Let’s begin with a few questions:

  • What kind of leather should be used?
  • Is it the top grain (smooth side) or suede (fuzzy side) best for my needs?
  • Is the strop mounted to a solid surface (paddle)?
  • Is it stretched on an adjustable frame (loom)?
  • Is it designed to hang on a hook like a barber’s strop?

Answering those requires knowing what kind of tool(s) needs to be cared for.

Generally speaking, knife makers and straight razor enthusiasts prefer the smooth, top grain side of leather. They rely on the natural texture of the leather to hone their blades to the absolute finest edge they can get.

The fuzzier side of the leather is preferred by many crafters including woodworkers and leathercrafters for its ability to hold stropping compound.

Width

Typically, most strops are about 2-½ inches (50-63mm) wide. A strop should be just wide enough to cover the entire length of the blade being honed/sharpened.

Recently, some have begun to make wider 3 inch (76mm) strops. The wider strop allows the entire blade to be pulled straight back across the length of the strop.

Type of Leather

There are essentially two kinds of leather that are used as strops: Vegetable Tanned and Oil Tanned Leather.

“Veg Tan” – Easily the most popular of the two, is named for the plant and tree tannin extracts used to cure or “tan” the animal hide. The secret of veg tan leather’s natural ability to maintain the edge of a blade is that the leather retains the majority of it’s microscopic silicates during the tanning process. It is what makes the smooth side of a high-grade veg tan leather strop without stropping compound on it, the best natural abrasive for the final step of sharpening the sharpest of blades.

Oil Tanned Leather begins as a chrome tan and then goes through an additional process to make it more supple. For stropping without compound, oil tan leather is still a popular option among both enthusiasts and professionals.

Generally speaking, knife makers and straight razor enthusiasts prefer the smooth, top grain side of leather.

Leather Surface Texture

Hard surface, or flexible? Rough grit or fine micro abrasions? Concave, flat or convex blade shape? Just as deciding what tool is right for the task at hand, deciding what surface to hone a cutting blade on depends on what it is and how it will be used.

While an axe needs to be sharp to chop wood, It’s cutting edge is ground at a different angle and the axe head itself is made of a different steel than that of a chef’s knife.

The knife’s blade, being thinner and designed to cut differently, needs a different honing texture and stropping technique.

A woodworker’s chisel needs to be razor sharp but lay absolutely flat to get the most effective cuts. This is best achieved using a hard, flat surface for stropping and the fuzzy side of the leather coated with a stropping compound.

The straight razor has long been the choice for men of all backgrounds. Getting the absolutely best shave depends on having the most finely honed blade. What we have learned over the course of a couple hundred years of stropping is that the final step using the top grain of veg tan or oil tan leather without any compound on it offers the finest hone/polish to only the very sharpest of blades.

Hanging Leather Strop

Types of Leather Strops

Strops and the act of stropping are interesting subjects. They bring together crafters, creators, professionals, hobbyists, knife makers, woodworkers, leathercrafters, barbers and more. Each person has a different requirement for the tools they need to hone, and so we will take a look at the various options that are most commonly used today.

Paddle Strop

Easily the most common type of strop available on the market today. The paddle strop is simply a piece of leather that is glued to a thicker piece of wood that has a handle on one end to hold. They can be found online with just a single pad of leather attached to one side, however, the more common is the double-sided variation.

Double Sided Paddle Strop

More commonly available, the double-sided version has two pieces of leather glued to either side. One piece is glued fuzzy side down so that the top grain can be used. The opposite side of the board has the smooth side glued down so that a stropping compound can be rubbed into the nap of the fuzzy side. This offers the most portability and versatility to hone/polish virtually any cutting edge to the largest group of users.

Loom Strop

A fascinating option for straight razor enthusiasts is a strip of leather mounted in a wood or metal frame known as a “Loom”. The leather is secured in the loom then kept taut by turning an adjustment screw.

Hanging Strop

Probably the most iconic and recognizable type of strop ever invented. The hanging strop has been featured in countless Hollywood movies and are sometimes found as an interior design element when a rustic look is desired. A hanging strop is still a very popular option among straight razor enthusiasts.

Antique Leather Strop

Occasionally, an antique strop can be found but they all vary in quality. If they have not been maintained, a visit with the local leatherworker or boot maker/repair shop may be required to restore the leather. If, on the other hand, the leather has been maintained, it may simply need to be cleaned and treated with a light coating of neatsfoot oil to bring it back to life.

Leather Green Sharpening Compound

How to Use a Leather Strop – Step by Step

  1. Apply a strop compound , or diamond spray if one is to be used
  2. Always draw the blade away from the strop to avoid cutting into the leather. Never, ever strop a blade by pushing the blade forward.
  3. It is important to make sure the entire length of the blade gets across the strop with every pull when using a strop that is narrower than the blade, This will provide the most even hone to the blade and go a long way towards the best outcome.
  4. Go slow. Slow down, maintain even pressure and take time to do it right. Those Hollywood movies showing the barber whipping his razor back and forth across the long hanging strop held stretched out in one hand was, well… Hollywood.

Those rules apply to everyone and every strop. Regardless of the kind of strop or which side of the leather is being used, learn the right way to do it, then build muscle memory by doing it over and over again.

Leather Strop Insights

Let’s try to answer a few common questions that arise when talking about stropping. Having some helpful knowledge can be beneficial for the stropping process.

How Does a Leather Strop Sharpen a Blade?

Stropping the blade regardless of what it is, is done to maintain that crisp, razor sharp edge. The strop is used to realign the microscopic pieces of metal along the edge.

Only when a stropping compound, diamond spray or paste is applied, does a strop actually “sharpen”. Each compound, paste or spray has a different grit and will remove metal at a different rate from the blade. Some will resharpen a dulled blade, while others are finer and designed to simply polish the metal.

Can a Leather Belt Be Used as a Strop?

A leather belt is a great option for a strop. In a pinch, if there is a way to sharpen the blade, then running it across a leather belt will knock the burr off leaving a crisp, clean edge.

Is a Leather Strop Necessary?

While it is the best option, Leather is not the only option. There are many great stropping materials that can be used. Wood – Balsa, Bass and Maple are commonly mentioned. However, if using a stropping compound, almost any wood will work.

Many things have been used as strops. Newsprint, magazines, denim jeans, cotton t-shirts, felt, and even heavy cardboard. Any surface that will hold a stropping compound and provide a flat surface to hone a blade on should work. Nylon is one that will not. It is too slippery and due to the way it is made, does not provide the surface necessary to properly hone a blade.

DIY Leather Strop

What Grit Is a Leather Strop?

It depends on many factors. Natural veg tanned leather has its own grit factor. What leather is being used, what kind of leather it is and what animal it is from. Deer, horse, cow, buffalo, kangaroo, bull, etc. They each have a different natural grit to their hides. Veg tan will have a different natural grit than oil tan.

If we start taking a look at the stropping compounds and diamond spray/paste options, the numbers begin to change. White is rated at 9000 grit which is more abrasive than green.

Green compound is rated at 50,000 grit.

Diamond spray/paste, which is common among many knife makers and straight razor enthusiasts, is available in grits from 15,000 to 160,000. It is applied to the top grain (smooth side) of the leather for the best results.

Leather Strop Care and Maintenance

Caring for a leather strop is easier now than ever before. Science and chemistry have given us a wide range of products to choose from. Strops that do not get stropping compounds on them tend to be easier to care for. A good cleaning followed by a light coating of leather conditioner will restore a faded strop.

Those that do use compound, first, need the layers of compound scraped, then brushed off the surface of the leather before it too can be cleaned, treated, and recoated with stropping compound.

In Closing

Leather strops are an essential piece of equipment for makers across a wide range of crafts and often, having just one is not enough. Good luck, stay sharp.