Thread: What Does it Mean, Taking an Edge too Far?

What Does it Mean, Taking an Edge too Far?

I admit, the 2nd shave on a newly honed blade seems better to me but I always thought that was the result of my lack of skill.

--james

homing...honing..and re honing some more..when the edge is perfectly capable..removal of excess steel IMO

Originally Posted by smalltank

homing...honing..and re honing some more..when the edge is perfectly capable..removal of excess steel IMO

Thanks. That makes complete sense to me.

To me it means that the edge is honed to an extreme beyond what the steel is able to hold.
In other words, the very apex of the edge gets too thin, and the steel simply will not be strong enough for it.
From what I remember, gssixgun has posted some number on at what level of micron thinness that happens, but i can't seem to remember what it was right now.

The critical issue with edge holding is angle and not polish. If a steel isn't hard enough for a very acute bevel angle, the edge will fail. But higher polish actually makes it more durable, the edge is more evenly and fully supported in all directions at a perfect polish.

I think "taking an edge too far" means different things to different people. I would call it a superfine honing of an edge, without any softness to the edge, where it's almost impossible to shave without weepers and the resulting razor burn that comes later in the day or the next day.

My answer is coming from my experiences sharpening KNIVES. I have also honed a few razors, but I have never taken them too far in my understanding of what this means.

1. Too far could mean removal of more steel than is necessary. How "necessary" is defined is a sticky topic...particularly with show knives. Some want to do whatever is necessary to make a VERY uniform and symmetrical bevel. It is possible to achieve high levels of sharpness with very odd looking bevels.

2. Too far (IMO) means refining an edge to levels beyond what is practical and sustainable by the steel and the geometry of the blade for its intended uses. This I have a lot of experience with in the knife world. I have had people request a pocket knife to be profiled at a certain angle, then have the bevels polished to a mirror finish, and the result needs to be HHT3 or better. While it is certainly possible for almost any steel available today on quality knives, I know of very few that will sustain this level of sharpness beyond a few basic cuts you might expect a pocket knife to perform (such as opening mail).

Razors have a MUCH narrower scope of work, but I would suggest that they can be taken too far also (by the second definition). I doubt that it is done often, but I suspect (without any evidence or data) that extensive stropping to finish a razor on compounds in the 600K range would fit my definition. Opinions probably vary

I'll pull this image if I have it wrong, but are the bottom two illustrations what you mean? As in the green material in the bottom is ground away and no longer supports the apex?

Yes but that is over simplified

Yes at any grit, but as stated in the first post it is very easy to correct,as you switch grits,, This is what the 4/8 pryamid was actually designed to eliminate,, By switching the grits and sneaking up on the edge you eliminate the "overhoning aspect" you are polishing and sharpening at the same time..
Using Slurry probably accomplishes that exact same thing, from the minute dulling effect of the slurry then the sharpening effect as you thin it out (Not Proved)

The basic geometry and sharpening require for Straight Razors as Dave pointed out should be rather straight forward, (pun intended) you do have a built in angle, so basically you push the edge across an abrasive and voila' a sharp edge.. BUT it just doesn't seem to work like that, there are other things coming into play, one is the pressure and another is the smooth part and to a lesser extent the shape of the edge (smiling blades change things)..

The simpliest honing is actually a heavy near wedge -IF- the geometry is right they do simply hone as you would expect, unfortunatly the geometry is rarely right so they become bears to hone

When I first joined SRP (please go look) most every honing issue in this forum was answered with either "Strop it again" or "You Over Honed it"
It took a ton of work from quite a few people to push the onus of correct honing to the bevel and not the finisher...Once that was done and more people began to get the "Honing" down, the "Overhoning" talk began to disappear..

Once you learn to relax after the bevel set and ease into the finishing stages then taking an edge to far should never be a problem.. and even if you do it is easy to fix..

What the OP was describing is probably just too much edge for him and his face, as he learns to strop better and better he will adjust that edge to his face.. As he gets better and better with shaving and adjusting pressure and angle the edge will also magically feel better Also people tend to move toward the razors that feel better on their face.. Everytime a razor doesn't do quite right it isn't always the razors fault, but yes you can create a fagile edge by Mis-Honing the blade

(if you wanted to go really advanced we could discuss my thoughts about why some stones work better for some steels)

Originally Posted by gssixgun

Yes but that is over simplified

Yeah, well, all models tend to be over simplified for demonstration purposes...if you want to get really technical about it, my apex angle is well outside the acceptable range for straight razors in those images.

and c'mon, look at my handwriting...you are lucky there is not coffee stains and lunch on this drawing!

Originally Posted by gssixgun

(if you wanted to go really advanced we could discuss my thoughts about why some stones work better for some steels)

Actually, this is something I might enjoy discussing at some point. I have developed similar hunches with regard to steels and hones for knives...it seems reasonable to think there could be good and bad marriages between steels and hones...but you have to be a few standard deviations away from the average hone job

There might be a better venue for such a discussion, but if you ever start one, send me a link

Originally Posted by gssixgun

(if you wanted to go really advanced we could discuss my thoughts about why some stones work better for some steels)

Go for it. I've not seen a lot of information about the alloys used on the first razors that got away from plainer carbon steels. We know a lot about the diemaking steels now (A2, O1, D2, and W1..what's left of it) in terms of what their carbides are, and what cuts them the best.

I haven't seen a lot about alloys from pre WWII, though, and how precisely they were hardened and tempered to avoid carbides (what they look like microscopically, etc). Regardless, anything with modern al-ox, ceramics alumina, silcon carbide, diamonds, chromium oxide - cuts them all, hard carbides or not.

Lee valley has just released a powder metal that sharpens about like A2, has about twice the wear resistance in wood, but seems to hold acute angles better even than carbon steel. It's not a high speed steel, and they won't divulge secrets, but if it holds acute angles and has no large particles, it would be fantastic for razors. It seems to do well in both chisels and plane irons, which pretty much covers damage due to impact (which hairs do) and adhesive wear (which strops do, and hairs probably do, too). If it has that kind of wear and impact resistance, but still can be sharpened on natural stones, it would straight up be better than anything out there right now that razor makers are carrying over from bearing steel, knife making steel or diemaking steels.