Honing: Troubleshooting Guide

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Identifying and Dealing with problems

Purpose of this guide:

  1. Help with identifying some common problems with a blade.
  2. Present some basis for honing theory, and some remedies for these blade problems.
  3. Present useful graphical representations that are not subject to poor camera angles, lighting, or resolution that could give someone an incorrect understanding of a problem.


Introduction: You never know what you’ll find

Sometimes it can be very difficult to know exactly what you are getting into when you buy a razor without holding it in your hand first, and without the experience necessary to identify blade problems.

As a case in point, this photo shows a variety of razors that revealed a variety of issues once they were “in-hand.”

For example, consider the issues with each of the razors below:

Numbered.jpg


  1. Xavier – gnarly looking razor, no honing problems
  2. Henckels –mostly even hone wear, slightly heavier wear on the toe
  3. Boker – nice even, but light wear. A well cared for blade.
  4. Rodgers- looked good in the pic, blade twists from toe to heel, kind of a pain to hone.
  5. Reynolds- nice smiling blade, even wear, no problems.
  6. W&B with the “W&B Warp,” not too bad, but enough to require some thought while honing.


The point here is that sometimes it can be difficult to evaluate a blade from photos alone. For this reason, it is a good idea for those who are new to straight razors to buy a blade from a known source before venturing out to an auction, or testing their luck at a shop. Even when someone has done their homework and read about problems with hone wear, there may be confusion to exactly what is meant by the term. Hopefully this guide will give users some basic concept for blade problems, how to identify them, and suggestions for correcting them.


Part 1. Basic Razor Anatomy:

Before going any further, it is useful to start with some basic razor terms that may help while reading this guide, and general razor knowledge.

Ranatomy.jpg

Now, we can move on to some basics of honing, as it applies to dealing with problem blades.


Part 2. Basic Honing Theory

Honing a razor can be a complex adventure because there are so many variables that can effect the process. From a very simplistic view, here are a few principles that may help establish a foundation for dealing with problem blades.

1. The Spine is a Guide

Razors are designed so that the spine acts as a guide for honing. If you start with a good, straight spine and an evenly ground razor, the edge should mirror the spine exactly. Any irregularity in the spine will be translated to the edge.

2. Even Strokes

You should hone with even pressure across all areas of the blade, contacting the same area on each side for the necessary amount of time in order to establish a good bevel.

3. The Torque Principle

In order for an edge to become sharp, it must be in contact with the hone. In many cases (especially with problem blades) adding a very slight amount of torque can help the honing process. The razor will be held so that the spine and edge contact the hone, and very faint hint of rotational force (edge toward hone) can be applied. Think of this as “introducing the edge” to the hone. It is worth restating that the spine still remains in contact, and this torque is very slight.


Here is an example of what is meant introducing the edge to the hone with slight torque.


Torq.jpg

Now that some of the principles of honing have been presented, it is useful to see how an ideal razor would look after years of proper honing (without tape to protect the spine).

In the following animation, you will see a new blade with a perfectly even bevel, and zero hone wear on the spine. As the razor rotates, you will see yellow areas that represent the bevel and hone wear that would be seen after many proper honing sessions.


Notice how the edge and the wear pattern (in yellow) are perfectly parallel and without any deviations. This relationship would be the same for a smiling blade as well. Again, the idea is that the wear on the edge mirrors the wear on the spine. So, while the bevel may change in size, and the spine of the razor may wear down, the proportions and blade profile will be the same.


Part 3. Problem Blades

In this section, some of the more common blade problems will be discussed as they relate to honing.

Some of the most common problems involve a chip, crack, or corrosion on the edge. Most of these problems are easily identified and require few special honing considerations. The following considerations may help with identifying and correcting these problems.

Chips and Corrosion:

How to spot It

  • You should be able to easily identify chips in the edge with a simple visual inspection
  • For very small (almost invisible) chips, a TNT may let you detect an issue
  • Corrosion or pitting will look like small pinholes or areas of rust/discoloration on the edge
Cracked.jpg


Pitting2.jpg
Likely causes
  • Anything that would chip a razor :D
  • Moisture, age, etc.

How to fix it

  • Hone on a low grit until you are through the chip, or corrosion entirely; you must get to clean steel
  • Bread-knifing and other such methods (knife-honing) may help you get past the problems quickly, but you will still need to completely set the bevel after these actions. In the end, you will have to remove all of the steel in the way of a clean bevel.

Notes: Pay special attention to removing all pitting from the edge. Sometimes this will require some magnification, but if you do not remove the corrosion you can end up with a crumbling edge or micro-chipping.


Cracks:

How to spot It

  • look for any obvious cracks or hair-thin lines
  • Pitting and other types of corrosion can mask some cracks, you will need to inspect your blades very closely
Cracked closeup.jpg

Likely causes

  • Dropping, dinging, or otherwise causing the razor to stress to the point of cracking

How to fix it

  • If you have a crack, you will need to assess if the crack is in a place where it can be removed without completely destroying the razor
  • You will have to remove the portion of the blade with a crack in order to have a safe razor
  • If the razor has particular sentimental value, consider cleaning, coating with renaissance wax, and storing for display only.

Note: Here is a photo of one solution to razor that was cracked near the heel. The entire crack needed to be removed. While this crack was in a salvageable location, you may not always be so fortunate. Shaving with a cracked blade is very dangerous. Be absolutely sure to ask if a razor has any cracks and negotiate a return policy in the event of a cracked blade prior to making a purchase.


Heavy Point/Toe Wear:

One of the next common problems deals with excessive wear on the point (toe) of the razor.
As mentioned before, straight razors are designed with their own built in honing guides. That said, there is no guarantee that the honing guides can’t be problematic (or become problematic). If improper honing results in irregular hone wear, that wear will naturally be translated to the razor’s edge as well.

A classic example of this principle is seen on a razor with excessive wear near the toe. As the spine is eaten away by hone wear, the corresponding bevel will grow in size. Eventually, the actual width of the razor will be disproportionally reduced following the wear pattern, and the razor will develop a nasty taper. This is often the result of applying more pressure to the toe of the razor throughout the honing stroke.

Here is a brief animation demonstrating a blade with excessive wear near the point.



Here are some notes for dealing with this kind of problem.

How to spot it

  • The bevel will grow in size as it approaches the point of the razor
  • Spine develops a distal taper (narrows as it approaches the point/toe
  • The overall width of the razor decreases near the point/toe

Likely causes

  • Excessive pressure on the point during honing strokes
  • The point area remains in contact for a longer duration during honing stroke

How to fix it

  • From this point on, make sure to use even pressure throughout the honing stroke
  • Add tape (or more tape) to the worn section on the spine

Notes: hopefully you catch this before too much wear accumulates. Once the razor suffers significant dimensional changes, it will be difficult to continue honing the point to shave readiness without worsening the problem. Take extra care when using strokes such as a rolling-x stroke. It is very easy to over-emphasize the rolling motion near the point in comparison to other parts of the blade.



Frown:

Another common problem is the frowning blade. This can be a time consuming issue, but depending on the severity, there are some keys to fixing this problem.

How to spot It

  • A frowning blade can usually be identified easily with a visual inspection of the blade. The middle portion will be thinner than the rest of the razor.
  • If you are not sure if you are actually seeing a frown, you can place the edge of the razor down on a known flat surface. If you see light at any point under the edge, you may have a frown.

Here is another brief animation demonstrating a frowning blade



Likely causes

  • Uneven pressure during honing strokes (heavy pressure on the middle of the blade)

How to fix it

  • Correct spine wear by protecting worn areas with tape while honing
  • Hone with carefully applied pressure to the areas with less wear, honing until an even bevel is established

This picture shows the honewear (yellow), and the portion of the blade that will need to be removed in order to make a completely new and straight bevel. (Although it would require less removal than shown here to simply achieve a blade without a frown)

Frown model whatneedstogo.jpg

This set of pictures shows the how the wear on the spine would need to change in order to be able to make this razor lay flat on a stone across the entire length. After a good spine has been established, this razor should not develop a frown again (with proper honing).


Frown removed.jpg


Frown model removed complete.jpg

While creating even honewear across a troubled blade would remedy many problems, adding the necessary amount of wear may not be an attractive idea to the owner of the blade.

In this case, the principle of honing on a guide still applies. However, if there are shallow points in the spine due to improper wear, those spots must be artificially “raised” in order to create a good honing guide. One common fix to this problem is the use of tape in the honing process.


Frown model wtape.jpg

This picture shows a layer of tape placed in order to build up the lowest point of the honewear. Honing with tape placed as shown here would serve to help reduce the frown, but the unprotected areas of the spine would be worn away. Another option would be to tape the entire spine, and add a few additional layers of tape to the low spots. This would prevent further wear, while correcting the edge. Applying tape while honing is a topic that has generated much debate, so I will address a few issues with using tape in the appendix.

Notes: Bread-knifing and knife-honing techniques may be used to quickly correct the edge of the blade, but a new bevel will still be needed. In order to make a lasting fix, the spine will need to be worn into an even pattern. Additionally, a user may decide to always hone with tape in order to compensate for the low spots on the spine.


Uneven Wear:

Another blade problem is uneven hone wear. In reality, most honing problems deal with some form of uneven wear. A razor with heavy point/toe wear, a frown, or a poor grind could all fall into this category. In this context, uneven honewear refers more directly to razors with radically irregular wear or poor grinds.


This blade has seen severe “honing abuse.” The irregularity and extent of wear will make achieving a good edge a real struggle. Notice how the edge wear mirrors the spine wear (red).

Unevengrind1.jpg

In a case this extreme, the only real option for correcting the damage is to regrind the razor. This is more complicated than taking a dremel to the blade, or modifying a point. This involves making a completely new master grind just as if it were being ground by the original maker. Notice how a straight point of contact on the spine has been created (red).

Unevengrind.jpg

On a razor with a heavy grind, there will be room for some error until you get to the final finishing. However, this is very tricky on an already hollow blade.

After seeing how years of uneven wear can sometimes be fixed with a proper regrind, uneven wear can also an indicator of an improper grind in the first place. Here is an amateur’s (:D) first attempt at grinding a razor.

Uneven1.jpg

The red shaded ovals indicate low areas in the grind. Since the metal has not been removed in a consistent hollow during the grinding, the bevel and areas of honewear on the spine much larger than on other areas. In order to correct this problem, the maker would need to continue finish grinding until the hollow is ground evenly from both heel to tip, and edge to spine.


While many of the points have already been addressed, here are some considerations for dealing with uneven wear.

How to spot It

  • Bevel width is irregular across the length of the blade
  • Blade width is irregular (frown)
  • Wear pattern on the spine is noticeably irregular across the length of the spine

Likely causes

  • Uneven pressure during honing strokes
  • Uneven master grind on razor
  • Some parts of the blade see more stone contact during honing than others

How to fix it

  • Correct spine by protecting worn areas with tape while honing
  • Hone with carefully applied pressure to the areas with less wear, honing until an even bevel is established
  • If the wear is very irregular and deep, a regrind may be the only option for correcting this problem

Notes: Fixing uneven wear can take a lot of time. You may need to use a very coarse stone in order to save time. Honing with circles and moderate to heavy pressure can speed this process significantly. The idea is to return the blade/guide system to how it was before the damage occurred. Once that goal has been reached, you can worry about setting a bevel, sharpening, and polishing your edge to shave ready.


Part 4. Structural Problems

The previous examples could be caused by misguided user actions, or through natural processes (such as corrosion). The following examples represent structural blade problems. These problems are very difficult to actually “fix,” so the recommendations presented here are intended to offer some useful considerations for honing these blades in order to keep them in a rotation.

Warped Blade:

How to spot it

  • Hold the spine of your razor on a table with the edge up toward the ceiling and look down on the blade, if there is a noticeable curve in the blade, you have a warp
  • Bevel on one side is wider at the point and heel, and wider in the middle on the other side of the razor

Likely causes

  • This is most likely a problem that occurred during the manufacturing process, or something that caused a structural deformation over time

How to fix it

  • Depending on the extent of the warp, you may have success when using a narrow hone. This will allow you to maintain good spine/edge contact and develop a decent edge on the inside curve of the warp. You may also need to use a slight rolling stroke on the side with the outside curve.
  • You may be able to hone this kind of blade with conventional approaches, but your bevel will appear uneven
  • The torque principle is critical on this type of razor
  • If the razor is a laminated wa-kamisori the warp may be straightened by careful bending. The soft iron & thin steel components make this possible.

Here is a graphic demonstrating what a portion of warped blade may look like.

Warp1.jpg

Notes: A warped blade can give you fits if you don’t identify it before honing. You may notice that the middle (or ends) of your blade is getting sharp while everything else remains dull. In this case a honer would likely start to second guess their technique. In an online auction, this kind of blade (and a twisted blade) can appear to be in great condition even with a high quality photo.


Twisted Blade:

How to spot it

  • Hold the spine of your razor on a table with the edge up toward the ceiling and look down on the blade. If you imagine the centerline of where the edge should be, you may notice that the blade leans to one side of center near the heel, and to the other at the point (or vice versa)
  • Bevel on one side is wider near the heel, and wider near the point on the other side of the razor
  • You may also notice that the razor seems to make good contact with the hone for a portion of the blade (or on one side of the blade), but not for other areas.

Likely causes

  • This is most likely a problem that occurred during the manufacturing process.

How to fix it

  • The defect in this blade is going to be an issue without a permanent fix; this will require attention each time it is honed to make sure that the bevel performs well.
  • A rolling-x stroke can be helpful to ensure that the entire bevel is honed evenly.
  • The torque principle is critical on this type of blade.


Here is a short animation showing what a portion of twisted blade might look like



Notes: Just like a warped blade, a twisted blade will puzzle you if you don’t see it before you start honing. If only certain parts seem to be getting sharp, take another hard look at your blade to see if you have a twist or a warp. Be wary of blades (especially old Sheffields IME) that appear to be perfect. Find out if there is a twist, or be ready to deal with one before you buy.


Part 5. Appendix

In this appendix, you’ll find more on the subject of honing with tape and examples of some of the common honing strokes.

Honing With Tape:

Honing with or without tape is a topic that has fueled much debate. The following comments are not meant to support one position over another, but to demonstrate some of the results of each method. As you can see in the following graphics, honing with tape will alter the bevel size somewhat, and eventually the angle of the bevel. Honing without tape will maintain the bevel angle for the most part, but honewear will become evident over time.

It has been argued that one difficulty that arises when honing with tape is that it can generate guesswork for the future maintenance of the razor. If someone hones a razor without tape, after a previous user honed with tape, they will need to remove more metal (due to the angle change from removing the tape) to get a good edge.

*The following images assume that the edge and spine have the same hardness. Some have found that the spines (especially on older sheffield blades) seem softer and tend to wear quicker than the steel at the edge. Keep this in mind as you consider honewear and the use of tape.*

This image shows how a razor honed with tape would look after 1/8” of the width is removed through consistent honing.

Hone wear side by side w-tape and dimensions 1.jpg

The dimensions shown here would only apply to this particular razor, but the general ideas stay the same. The main takeaway from this picture is that over time, a razor honed with tape will have a smaller bevel. This is due to the ever-increasing bevel angle caused by the loss of blade width, without the accompanying hone wear on the spine.


On the other hand, a razor honed without tape to a 1/8” reduction in width.


Here we can see the change in the bevel angle after 1/8” of blade loss due to honing.

Tape angles.jpg

Vs. the relative lack of change in angle after honing without tape.

Notape angles.jpg

Honing Strokes:

The following animations show some of the more common honing strokes, and an example of bread-knifing.


X-Stroke

Xstrokeanimation.gif


Circles
Circles.gif


Rolling-X

Rollingxfront.gif


Bread-Knifing

Bknifet.gif


Knife-Honing:

The basic concept is to hone as usual, but lift the spine a small degree off of the hone. This focuses the metal removal on a small portion of the edge, allowing to remove defects quickly, or establish a pre-bevel. Regular bevel setting after this step will still be required.