Thread: Overhoning

Can anyone point this relative noob to a "sticky" or source of info about just exactly what "overhoning" is, how to recognize it, and how to deal with it? I know that there is a lot of information spread out over thousands of posts, but I'm wondering if there is something a bit more focussed that I can look at. I've read a bunch about the "wire edge" and so forth, but I don't think I've ever actually seen one on any of my razors. Instead, what I seem to wind up with is an uneven, jagged edge with little pieces missing here and there, when viewed through a 'scope at 60X-100X. Running such an edge down a wooden matchstick doesn't seem to do much, nor does "backhoning", as far as I have been able to tell.

Any advice is greatly appreciated.

blessings,
denis

P.S. Our late, lamented friend Ray Dupont gave me a Feather DX Artist Club about three years ago, and it consistently gives me the best shaves I've ever had. THAT'S what I aspire to, with my honing. I know: "Good luck!"

What you're describing could be microchips, or it could be overhoning. Usually with overhoning the matchstick will remove most of this.

In the thread "hones and edges under the microscope" in this section, take a look at the edge honed by the 15k shapton. See the rectangular chunk missing from the edge on the left side of the photo? (edit: I misremembered, it's almost exactly in the middle) That's characteristic of overhoning - a piece of the wire edge has broken off (keep in mind these were at 200x, not 100x). On a badly overhoned razor this sort of feature will be more prevalent. On a microchipping blade the chips will be more semicircular; they will look kind of like the serrations on a flint arrowhead.

If you're honing a vintage razor there's another likely possibility: the edge may be rotten from decades of oxidation. You will eventually hone through this to good steel, and the razor will start honing normally. But sometimes it can take awhile, even on a fast hone like the norton.

I agree with mparker. No matter what the cause, in your case I would go to the 4000 grit and hone until the edge looks uniform and passes the thumbnail test. Then move on to the 8000 grit, strop and test shave.

Keep us informed of your progress,

...to you guys. Since I'm still in that uncomfortable place where folks who haven't yet learned how to hone are trying to establish a reliable feedback loop between what they do with the hone and what the results look and feel like, I had another plan: I was going to go about 100 laps on an 800 grit stone, a 1K stone, and then a 1.2K stone, using Japanese "nagura" slurry, just to see what would happen. But based on the replies to this thread, I'm thinking that might just make things worse, and that it might be better to go right to my 4k. Two questions, then: Shall I use the nagura stone on the Norton 4K to create a slurry? And, any ideas at all about roughly how many laps? I know that can't really be determined without seeing the blade (BTW, it's a decent-but-unremarkable Gregg Howe Sterling Special No. 1001, 6/8), but are we likely to be talking more like 50, or more like 1000?

Thanks as always for your time.

>>>denis

Originally Posted by grunion

...to you guys. Since I'm still in that uncomfortable place where folks who haven't yet learned how to hone are trying to establish a reliable feedback loop between what they do with the hone and what the results look and feel like, I had another plan: I was going to go about 100 laps on an 800 grit stone, a 1K stone, and then a 1.2K stone, using Japanese "nagura" slurry, just to see what would happen. But based on the replies to this thread, I'm thinking that might just make things worse, and that it might be better to go right to my 4k. Two questions, then: Shall I use the nagura stone on the Norton 4K to create a slurry? And, any ideas at all about roughly how many laps? I know that can't really be determined without seeing the blade (BTW, it's a decent-but-unremarkable Gregg Howe Sterling Special No. 1001, 6/8), but are we likely to be talking more like 50, or more like 1000?

Thanks as always for your time.

>>>denis

You do not need to use a slurry/nagura stone on the Norton. You should probably be looking at between 50-100 laps on the 4K not anywhere near 1000 if there are no micro-chips in the blade. I would recommend doing a search for "pyramid" because Lynn's pyramid method is a very common way to consistently and quickly get a razor sharp, especially if you don't really know what you are looking for with respect to sharpness.

Originally Posted by grunion

...to you guys. Since I'm still in that uncomfortable place where folks who haven't yet learned how to hone are trying to establish a reliable feedback loop between what they do with the hone and what the results look and feel like, I had another plan: I was going to go about 100 laps on an 800 grit stone, a 1K stone, and then a 1.2K stone, using Japanese "nagura" slurry, just to see what would happen. But based on the replies to this thread, I'm thinking that might just make things worse, and that it might be better to go right to my 4k. Two questions, then: Shall I use the nagura stone on the Norton 4K to create a slurry? And, any ideas at all about roughly how many laps? I know that can't really be determined without seeing the blade (BTW, it's a decent-but-unremarkable Gregg Howe Sterling Special No. 1001, 6/8), but are we likely to be talking more like 50, or more like 1000?

Thanks as always for your time.

>>>denis

I agree, 50-100 should easily take care of it. If not then there is something else going on, like how much pressure your using or your stroke. Use 1-2 lbs of pressure for the first half of your strokes then lighten up for the last half. Check your edge every 25 laps. I do not use a slurry on my 4K or 8K and I always "refresh" my hone surface between each honing session.

Following the useful hints in this thread, I went about 100 laps on a 4K stone, and got mixed results. Through the microscope at 60X, the edge clearly still has several jagged places. They may be a bit less pronounced than they were, but it's hard to say. However, in addition I noticed that the part of the blade nearest the heel was indeed getting sharper, as indicated by the wet thumbnail test; it also looks good through the 'scope. So my question is, if you have a blade that seems to be improving over part of its length, but not over another part or parts, what would be the strategy to use?

Thanks always,
denis

You need to make sure the hone is hitting the bevel evenly along the whole edge. One easy way to do this is to color the bevel with a magic marker then give it a few laps on the 4k. The magic marker should be taken off along the entire bevel, and the shiny metal should extend all the way to the edge. It may help to look at it under the microscope to make sure - even thin areas where the magic marker is still left will jump out at you under magnification.

If the hone is hitting evenly, then you just need to keep at it on the 4k, maybe add some pressure till the chips are gone. If the hone isn't hitting evenly, then you need to diagnose what the problem is and correct it.

Does your razor have a straight edge, a smile shaped edge or a tapered edge?

Your note struck a chord with me. I miss Ray Dupont also and always had excellent dealings with him. I hope he's getting heavenly shaves now! I share your inquisitiveness about overhoning. Many of us have overhoned and know when it happens. In my opinion it's a different effect than getting a wire edge. Wire edges and their subsequent removal are (we are told) the way to go on plane irons and wood chisels. I don't like wire edges even on plane irons or chisels and certainly not on razors! As a knifemaker I go to extraordinary lengths to get the edge of the steel to the optimum hardness and don't like losing a wire off of that every time I sharpen the knife. Think about it. Lose that much steel a hundred times and you've significantly shortened the lifespan of the blade. One of the advantages of doing your own heat treating is being able to heat treat in the "zone method" where the tradeoffs between hardness and brittleness are controlled through quenching. You want to go for a hard edge with a soft backbone for resiliency.

ANYWAY, I'd love to see a scientific study of overhoning and maybe we can convince Tim Zowada to "put it on the list" and do a comparative photo study. Overhoning is not well understood and my customers tell me the problem is usually encountered with Shapton 12k and 15k stones which they subsequently sell on eBay. This is not a knock to Shapton as those stones are awesome tools but should be used for other purposes than razor honing. That is just empirical data though!