In your honing journey you will encounter razors that are obviously in complete defiance of our desires to set the bevel, run the progression, and finish to a shave ready state. Some will be new razors that are poorly or incompletely ground, and some will be poorly honed or over honed in the course of many decades, or victims of carelessness with resulting damage. Some of these defects include:
Razors with such defects are not prime candidates for a newbie to hone. The normal bevel setting grits can't do the job, or require tens of thousands of laps to remove the tremendous amount of steel required to leave a well formed bevel on the razor. This is usually an unacceptable commitment of time and effort, and likewise an excessive amount of wear on a valuable stone or on multiple pieces of sandpaper or lapping film. So, much coarser media are used to do the heavy lifting prior to hitting the usual bevel setter. Greater demands are made of the skill and experience of the honer. And even an experienced honer of great talent will often decline to hone some of these razors, depending on the magnitude of the problem and the expected low value or usefulness of the razor after repair and honing. As a beginner, you are well advised to set such razors aside for further evaluation and action a year or a few years down the line.
However if you have reached the point where you are ready for such a challenge, I will endeavor to help you with some of these problems, with the understanding that you are now departing from The Method and entering into a more advanced level of the edgesmith's art. As you accept more challenging blades to rehabilitate, you will no longer be painting by the numbers. You will be learning what makes a razor, a razor. You will be learning how to manipulate the steel into a working tool in spite of poor craftsmanship by the maker, or amateurish honing or careless use or storage over perhaps more than a human lifetime. Such strong medicine is not without risk, and an otherwise valuable razor might be best left in the care of an experienced and renowned honer. I urge you to first of all not attempt to address such a razor until you have made your chops on dozens of simpler razors, and second to only put at risk razors of no particularly great value, and thirdly, be prepared to accept failure as a possible consequence of the learning process.
When operating on the outer fringes of the honing art as opposed to religiously following The Method on easy razors, you will need mentors and you will need research resources. And so I strongly urge you to join one or more straight razor discussion forums. Below are three that I happen to belong to.
Perhaps the most common injury to a razor that you might have to repair is the frowning edge. The frown is so called because with the razor held spine up, edge down, the edge of the razor is frown shaped. The center part of the edge is honed away more strongly than the ends. When you attempt to hone normally on a reasonably wide honing surface, the central portion of the edge does not make contact unless you use a very wide x stroke on a narrow hone. This is of course unacceptable. Yes, you can with iffy results hone into the frown, but better to correct it now. The way to do this is to simply hone it.
Many well meaning honers will tell you to do things differently, but if you have created several Method edges, you know that I won't set you onto a path that does not lead toward success. If you are here then you seek a deeper understanding and a mastery of the razor, but I am still here for you and I will tell you how I would have you do this. By all means, depart from the way now, if you wish, or if you have been swayed by the differing opinions of other knowledgeable honers, but you already know what happens when you follow my instructions, which here you may regard more as strong suggestions meant to guide you toward mastery rather than to serve simply as a cookbook formula.
Obviously, major amounts of steel will have to be removed, and to do this, a coarse medium is needed. HOW coarse depends on the amount of steel, and the preferences of the honer. But a bad frown to me calls for as coarse as 100 grit to start with. A slight frown I might begin with maybe 400 grit. The laws of progressive honing still apply. If you put 100 grit scratches on the bevel, then they will at some point need to be honed out. And the succeeding scratch pattern, too. And the next as well. Running this megaprogression of extremely coarse grits in itself uses up a lot of steel. So it is good, in fact essential, to lose this steel before the repair is complete, so you are removing only steel that must be removed, anyway. So as the razor's edge becomes straight again, and as the deepest part of the frown comes close to making hone contact, begin moving up into finer grits. The rate of change and the exact point where you begin progressing is a very subjective thing and there is no real formula. You will normally rely on your own experience, but with no experience to rely on, you are sort of guessing and you might start late or early, or progress through the coarse grits too quickly or too slowly. That's okay, especially if this is an expendable razor. Remember, you are not just doing. You are learning. It is a process rather than an event.
The bevel is not just the honed strip at the edge of the razor. The bevel is also the honed strip on the spine. You are removing steel from both edge and spine. This is natural and normal. What you must avoid is wearing the spine or the edge disproportionally, which would change the bevel angle. (Cue more howls of outrage from the "experts".) If you disregard the requirement for proportional wear of BOTH spine and edge, in hormal honing, change in bevel angle is very slow, and many guys could care less whether their bevel angle changes a degree over 30 years or so. But in correcting a frown that took 30 years of bad honing to create, you are removing an awful lot of steel. And so bevel angle change is a very real thing. Many honers pick just such times to tape the spine of the razor to "protect" it. This is actually the WORST time to tape the spine. So don't use tape unless you calculate a bevel angle that is already too acute.
On the other hand, you must not wear away spine steel too quickly, either. It must be in reasonable proportion to the blade width that is lost through honing the edge. Most newbies will have a tendency to apply too much pressure to the spine and not enough to the edge, when removing serious amounts of steel. And so you need to slightly torque the edge down to compensate. The tang of the razor is more nearly inline with the spine, and so when using heavy pressure, naturally more of the pressure is directed to the spine than what is good for the razor. Again, I can't give you any metrics to follow. You are on your own, either going by experience, or learning by it. You will probably make mistakes. Expendable razor, right? I hope so.
Normally it is a bad idea to rest a finger on the blade as you hone. The thin steel is more flexible than you realize, and you will cause uneven hone wear rather than correct it. The heavier the pressure, the worse the effect. However, in the initial stage of frown correction, it is okay to lay the finger along the blade to help with pressure distribution. A LOT of steel is coming off, and you will have time to correct imbalanced wear. The important thing is that during the heavylift stage, you are wearing the edge steel away along with the spine, in correct proportions.
So, select your initial edge correction medium. It can be a stone, if it is well lapped and not so soft that it needs lapping during the course of the job. A diamond plate that has been broken in is good. They usually cut very aggressively, and do not dish from use to any appreciable degree. Be aware that cheap diamond plates such as the ones Harbor Freight sells, are not very flat. They can be useful as you begin the process but once well into correction, you will need to replace them with something flat and true. 60u lapping film has been used for this. I have a 320 grit Shapton Kuromaku stone that I sometimes use for this, and a 600 grit Chosera to follow up. This works well for smaller frowns. For a deeper one I begin with 100 grit red resin type wet/dry sandpaper glued to one of my acrylic plates. You could do far worse than to start with this, or maybe a bit finer, say 220 grit. The coarser the grit, the greater magnitude of damage you yourself inflict on the razor through any mistakes you make. The finer the grit, the longer it will take to complete the task, and the more likely you are to leave it unfinished or begin progressing too soon and too quickly.
Honing out a frown is one time when the use of an X stroke is not a good idea. You should always keep the shoulder of the razor right up to the edge of the hone. Improper use of the X stroke, with too much heel end pressure, is what likely created the frown in the first place. You want to hone straight and flat, and normalize the edge into a straight line. Some guys will breadknife such a razor to initially straighten the edge but this is a bad idea. Remember about proportional wear to spine and edge? Breadknifing is when you stand the razor up on its edge and hone the edge away until it is straight. There are variations, where you elevate the spine to say 45 degrees to speed up steel removal, but again this is obviously a bad idea. Just hone it flat and true, and gitter done.
So, apply sharpie to the existing bevel, and do a few back and forth laps on just the show side of the razor. Now look at what you got. You can see where you do and do not make contact. Where the ink is honed away, is where more steel will need to be honed away. Where the ink is untouched, is how deeply you will have to hone into the razor before the bevel is set. Go ahead and do a set of 50 laps and see what it looks like. Maybe the contact areas begin to expand up and down the edge of the razor? Are you whittling away at the uncontacted areas? Great. FLip and do the other side the same number of laps. Keep going with these sets until the uncontacted area is almost gone, then bump it up a grit. You will find in short order that you are raising a burr on one side and then the other. This is of no consequence in the areas that have excess steel to be removed, but you don't want to start raising a burr along that last bit of frown just yet. At some point then, you will transition to alternating laps, or normal honing. Go on this grit until no part of the bevel remains uncontacted. The edge will still not be fully developed in the deep of the frown. You will do that in the next grit, preferably something in the 600 to 800 range.
As the last bit of frown develops an apex, you need to transition to the normal bevel setting grit, or maybe the next higher grit in your normal honing progression, or some point in between. If you lightly drag the edge of the razor across the base of your thumbnail, you can tell what parts cut eagerly because they will seem to stick to the thumbnail, and what parts skip over because they are not sharp yet. You can also examine the edge under a very bright light with a magnifying device of your choice. You COULD do a standard burr method bevel set, but hey, you already basically did that over 90% of the edge, so do you really want to go there? The good news is it won't take much to raise that burr except on the deepest part of the frown where the edge is last to develop. Your choice here. Remember, you are not Method honing. You are not doing, you are learning. This is not an event, this is a process. Your eye and your feel are your guides. Develop your skill and then rely on it.
Once your edge is straight and the bevel well set, you are good to go with good ol' method honing on lapping film.
One thing that can go wrong is when the reason for the frown is a badly warped or bent razor. This will be obvious early in the correction process, when the deep part of the frown makes contact on one side of the razor but not the other. If the amount of warp is too great, you might not be able to achieve a proper bevel, or you might have to hone quite deeply into the razor. Remember though, that it is absolutely not necessary that the bevel surface be of consistent width up and down the edge, nor equal on both sides. The only thing that is really important is that there BE a bevel, and a good apex where the two bevel planes intersect. If the razor is bent then there will be a notable lack of consistency in the bevel surface width. Don't feel no way about that. In extreme cases, the razor will need to be bent back straight again, or discarded. If you ever tried to do this, you were probably dismayed to find that it was basically impossible to bend the razor even slightly without breaking it. The way to do it is under control, in a vise. The jaws should be smooth ones for this, or else lay angle iron over the jaws. At the deepest part of the bend, station a piece of silver-nickel pinning stock on the outside side of the bend. Secure it temporarily with a drop of hot melt glue or whatever. It must of course extend upward across the spine. To the other side of the razor, fix two more short pieces of pin stock near the heel and toe of the razor, in similar fashion. Obviously when you place this assembly between the vise jaws and tighten the vise, a reverse bend will be caused by the presence of the pins. Being of softer material than hardened steel, damage will be minimal. The springiness of the steel should prevent actual permanent over-bending, and the diameter of the pins should be just about right for ensuring that the razor is permanently bent just the right amount to give you a straightened blade. The first few times you try this yourself, once again I urge you to not perform this operation on a precious heirloom or a valuable razor. Not IF, but WHEN things go wrong, you need to be philosophical about it and not heartbroken.
The techniques used in dealing with a frown apply to fixing many different defects. Use your judgement. But not everything can be easily fixed through just honing the razor. With age, use, and vigorous honing, a stabilizer can begin to intrude into the honing plane as the body of the blade is worn by the hones. Eventually the heel of the razor extends beyond the true edge of the razor. We call this a heel hook. Every case is different. You can correct some by honing the hook away on the edge of a coarse stone. You can sand them away with a custom sanding block. You can reduce them on a belt grinder, belt sander, or with the notorious Dremel or one of its knockoffs. Danger lurks here, both to the razor and to the honer. Dremels in particular have ruined a lot of razors, and injured a few operators. Your precious razors should be sent to a competent and experienced expert. Then again, is a razor with a pronounced heel hook particularly precious anyway? Your call.
To me, power tools are essential for the heavy lifting of this type of repair. A Dremel kit usually comes with all sorts of little grinding stones and wheels and disks. The one of greatest interest here is the little sanding drum attachment. It is a rubber arbor over which a sanding drum is placed. A screw in the end screws into the shaft to expand the rubber part, holding the cardboard sanding drum securely. These cut quickly and cleanly, and are maybe a bit easier to control than the various grinding stone implements or diamond burrs. As we often say in the razor forums, YMMV. (Your Mileage May Vary) If you elect to use a Dremel or other power tool for working on razors, then safety must be your absolute top priority. You can give yourself a debilitating cut or lose an eye with this little beastie. And you will certainly shatter more than one razor in your career as an edgesmith. This is sort of like going in for an appendectomy and as you go under the anesthetic, you see the surgeon revving up a chainsaw. In skilled and experienced hands, mishaps are fewer and farther between, but they still happen. Keep this in mind.
Be careful and be safe, use eye and face protection, and be always cognizant of the rotational direction of the tool and where it is in relation to the edge of the razor. The most breathtaking destructive events occur when the tool grabs the edge and shatters or flings the razor with razor or pieces of it traveling at ballistic speeds. It happens so fast that your heart skips a beat as you process what the hell just happened. Yeah, count your eyeballs, make sure you still have the standard issue of one pair. If you are lucky the razor is still intact and can be salvaged, or at least made into a shorty. Another common catastrophe is overheating. The edge of the razor is very thin. It doesn't take a huge application of heat to heat up the edge faster than the heat can dissipate into the body of the blade. We are talking about nearly a molecular level. We are talking about an area of the blade so small that heating is not easily felt or monitored. This is a very delicate bit of steel. Up to about 300f degrees, no biggie. AT THE EDGE. But if you get over about 350 degrees, you could be pushing the temper, softening the steel, effecting the ability of the steel to take and hold an edge. The razor can easily be rendered useless through overheating. Sometimes the razor can be heavily honed back into unaffected steel, but this is a crapshoot. The thick areas of the razor can easily take 20 or 30 seconds of grinding, and as long as the razor is still not too hot to hold you are perfectly save. The thin parts are another matter. You can achieve the Blue Stain of Death, or BSOD, in as little as three seconds on a very small scale. And so the procedure at or near the edge or a corner is to just touch the drum to the razor for a second or so, then cool.
Cooling can be by water or ice water dip, or ambient air cooling. Whatever. The important thing is that the razor ends up at room temp or cooler before hitting it with the Dremel again. Your experience will have to guide you here. 20 seconds of cooling might allow the heat to dissapate into the razor. Or maybe not. Some guys rest the blade on a steel, copper, or aluminum plate which serves partly as an edge guard and partly as a heat sink. YMMV, again.
There are two main techniques for steel removal when correcting heel hook or intrusive stabilizer. You can remove steel from the side of the defect to make it parallel to the rest of the blade, or you can remove the last bit of heel altogether instead of thinning it. And even here you can choose to create a thumb notch by grinding perpendicularly to the central plane of the razor, or round the heel off. The thumbnotch technique is perhaps the most straightforward way but you are making a drastic change to the profile of the razor. This is commonly performed, or in the past was performed, on new out of the box Gold Dollars to make them easier to hone. Not so much on other new razors of better grind, or vintage razors, but just be aware that the option exists. For razors of better quality, rounding off of the heel is more common, and skilled honers often choose to just thin down the stabilizer and heel.
Inexpert grinding often leaves the blade thicker for an unacceptably wide portion of the blade adjacent to the stabilizer. This is really what contributes the most to heel hook formation. One way to correct this is to grind away stabilizer and excess thickness from the side of the heel on a coarse stone or plate and sandpaper. A single layer of tape completely around the entire blade toward the toe end will help to keep the rest of the blade from bearing on the hone while you concentrate pressure on the problem area. The point of the heel gets honed a bit more than actually required for restoring the blade's geometry, to allow for future honing. This results in the greatest preservation of the original profile but requires the most skill. You can do the grunt work on a belt sander's nose, or on a belt grinder, or with a dremel and sanding drum, if you feel like taking a big chance.
Once this repair is complete, you may want to hand sand to fair the fresh grinding in with the rest of the blade, and equalize the finish between old and new grinding. You can start with 400 grit wet/dry sandpaper, or maybe 600. Sand until the surface is nice and even. Get it right, VERY right, at this stage. Don't try to make 2000 grit do the heavy work. On the other hand, excessive sanding at coarse grits can materially reduce the blade thickness to less than optimum thickness, so be careful. Choose your starting grit carefully, get it done and done completely, and then progress through finer grits to reduce scratch depth and make it shine.
There are two major styles of hand sanding a razor. You can use a piece of flexible hose as a sanding block that conforms to the shape of the razor. Or you can take a small piece of sandpaper and fold it over the spine of the razor so that it extends to the edge and beyond, then pinch the whole works between thumb and forefinger and run the razor in and out through the folded sandpaper. The web of the hand goes around the spine, not the edge. That edge will CUT you, badly, even though it might not be shave ready. You can do considerable damage to your hand in a fumbly bit of inattention. Always have the edge pointing out away from your hand!!!
A progression to 2k grit works nicely to restore to a matte finish. For a mirror-like polish, you will need a progression of diamond pastes and bits of an old tshirt, used in similar fashion to the sandpaper. With an eye on safety, you could use the dremel and a cloth or felt wheel loaded with diamond paste. Be sure to do this with the razor resting flat on a metal plate, to protect the fragile edge from kinetic damage as well as heat damage. A lot of razors have been rendered useless through DBB, or Death By Buffing. A buffing wheel can heat up a thin edge almost as quickly as a sanding drum or grinding stone.
I will not at this time go into greater detail on these fixes, nor will I go into repair situations mentioned earlier but not covered in depth so far. Except for one more very common defect. The upswept toe. This can result from the factory grinding, or from faulty honing. Commonly, the specific cause is that the honer of several years allowed the shoulder of the razor to ride up on the hone. This lifts the heel end and sends the pressure to the toe, honing it away. In time the toe begins to curve upward. Straight honing correctly will no longer give contact at the toe. Get ready for more howls of outrage. The conventional wisdom is to utilize the rolling X stroke, lifting the heel end of the razor so the toe is forced into contact. And so, the toe gets sharp. It gets sharp like any other edge gets sharp, through the removal of steel. The upswept toe does not get corrected, only sharpened and worn away still further. The problem of the upsweep is not corrected. The dull toe gets sharp, but the root problem only worsens due to deliberate targeting of the toe.
Let's look at the pros and cons then, of doing this. The benefit is what, exactly, of targeting the dull toe? A sharp toe. The sharp toe is important... why, exactly? A sharp toe causes a lot of the worst sort of shaving cuts. Often a sharp toe is deliberately muted, for safety. The toe is simply not very important in the course of a typical shave. So you gain nothing, really, by ensuring that the last little bit of edge will shave. So generally NO ADVANTAGE to "rolling the x" to specifically hit the toe. However, I have already mentioned the DISADVANTAGES of doing so. Therefore I opine that disregarding an upswept toe is best, unless the unhoned edge section is quite long.
If you have let's say a half inch of uncontacted edge, then you need to take action. Simply treat the razor as if it had a slight smile. Use the "rolling x" stroke. To do this, you begin the razor stroke with a slight excess of pressure at or near the heel of the razor and perform an x stroke, pulling the razor slightly to the right as you push it away from your or pull it toward you. As the razor travels across the hone, the weight is shifted out toward the toe. This is done by pushing down or lifting up on the tang, respectively. The rolling x stroke is a valuable technique in honing smiling edges, and we can adapt it here to incremental correction of the upswept toe.
The biggest problem with the rolling x stroke is that the roll is usually overdone, especially by beginners. This makes the smile bigger, more pronounced. Not necessarily a terrible terrible thing, but it does make the edge less like a straight edge. If you overbake the rolling x in an effort to correct the upswept toe, you are right back at square one, making the problem worse.
Here is how to approach this sensibly. Do a quick sharpie test with a more or less normal honing stroke. With your sharpie, mark in the hollowgrind where contact ends on the edge and the upswept toe dodges contact, This is point A. Now make a mark B where the edge normally would end. Halfway between them, make a mark C. Mark C is a target point. The focus of pressure will extend out to point C and no further. Do similar at the heel. Now go into edge repair mode, on a 400 grit or so stone. The Kuromaku stone I mentioned earlier is excellent for this, as is the Naniwa Chosera. These are fast, reasonably hard stones ideally suited to heavy work on wonky razors. If you don't want to drop the coin for these sort of expensive rocks, just glue sandpaper to your acrylic plate.
You can go right into plain old alternating laps with the rolling x stroke, but I prefer to use back and forth sets on one side at a time. I rest a finger on the desired pressure focus point, and use moderate pressure, the weight of my forearm or a bit less. The focus never goes beyond the marked points but also does not linger in the middle part of the razor. You are basically creating a slight smile where there maybe was none before. in an effort to incorporate part of the errant toe into the working edge. The result should be a nice smooth curve and a tippy toe that is not honed. Once the desired degree of inclusion is reached, go to your 600 and 1000 grit hones, get a good bevel set, and complete the progression and finish. The razor will handle nicely and appearance will be somewhat improved.
Once you have tackled a few problem razors with these techniques, you should be able to figure out the rest. Remember the forums. Ask questions there. You will get a lot of different opinions. Beware the preponderance of responses from internet parrots that simply repeat the same tired old urban legends. Look for well reasoned arguments for this way or that way to get something done, and finally make an informed decision based on the responses you get. Your goal is not to minimize the howls of outrage. Your goal is to give you the edge you are looking for, on a poorly made or poorly treated razor, and make it a good shaver.