Micro-Bevel?

[Razor]

Is this really needed? I have been sharpening my knives on the sharpmaker in the 30 degrees slot and so far so good. Just wondering.

 

[adamlau]

If so far, so good then probably not. Why not try out micro? You may prefer lower sharpness with improved longevity. Or you may not. Never know until you try. Ensure your entire edge bevel is ground to 30, then add on a 40 micro and see for yourself.

 

[samuraistuart]

I've been using micro bevels lately. My main edge previously was just a simple 15° per side, lately I've been playing around with 10° "back bevel", with the 15° micro. The finer grain the steel is at a given hardness, you can take it to a lower angle.

 

[Mo2]

Micro bevels are great for if your getting chipping like with s110v or the like. It also seems to last longer but I've not seen a test done to show that (has anyone else? Link?)

 

[jbarsquat]

It's not needed, but it is helpful for certain applications. For me, my kitchen slicers don't stay sharp for long enough if I don't put a microbevel on. 14 or 15 dps with an 18 or 20 dps microbevel and now I can go 2-3 times as long between sharpening.

 

[Tim the Wizard]

I like microbevels and i'll tell you why. Sometimes it can be difficult to tell if your nice edge is really a wire edge or a weak piece of straightened out burr. When I microbevel, I am ensuring removal of any final burr. I only move up a degree or so. It has worked well in conjuction with stropping. For example I just worked on my personal EDC at 30 degrees inclusive, with the microbevel at 32 degrees inclusive. This also adds roughly a micrometer of convexity once blended with the strop.

 

[brasileiro]

My own experience was that I did not believe in microbevel until I work one.
I tested it on a cheap kitchen knife. 10dps with 20dps micro. It was July 1st and then I let everybody that was using kitchen use that knife. So yesterday I come back to have a look at edge and it was ok. Cutting, slicing... but I saw some bright spots on the very edge. Believe me, with 7 strokes per side, light strokes, very light strokes, very very light strokes (I was carrying lifting the knife) and I had de edge back.
I did the back bevel using a #1000 Japanese whetstone I also use it to build the microbevel on July 1st. When I came back I hasn't that stone with me and I used a carborundum #320 grit to do it again. Cutting like brand new knife.
What I learned with it:
1-Microbevels with low angle back bevel require touchups frequently.
2-Single bevels with high angles has more durability.
3-But... micro bevels are far away from single easier to retouch while single has more hard work when it gets dull.

 

[Obsessed with Edges]

I used to apply a microbevel, back in the days when that was the easiest way for me to touch up an edge. At the time, I had trouble feeling the original bevels and/or maintaining the necessary angle stability on the bevel itself; so, a couple or three very, very light passes at what I could feel to be a higher angle was the simplest path to a crisp apex again.

Since then, I've moved on to sharpening all of my edges at lower angles; all seem to finish somewhere in the 25-30° inclusive range, where my natural hold puts it. Since I've been doing that, and since I no longer have trouble feeling the original bevels I've created, I no longer see the need for a microbevel on my own knives. Sharpening at a more acute angle will naturally thin the edge more, over time; these thinner edges are inherently easier and quicker to touch up 'as is', without having to microbevel. There's also no need to remove more steel than necessary, touching up edges done this way.

Whether there's any difference in edge durability, I haven't seen a significant difference. A microbevel, which is inherently wider by definition, will never cut as well from the beginning as the inherently thinner edge without that microbevel, properly and fully apexed. So if there's any edge damage needing fixed with a thinner edge, it's more than likely just a little bit of edge roll that can be easily fixed by 'steeling' the edge, or with some very light passes on a fine stone or mildly aggressive strop.


David

 

[adamlau]

I always add a 15 micro to 10-12 edges. Tip often sees a 20 micro. Particularly with kitchen knives. Epicurean boards are not as knife-friendly as advertised.

 

[brasileiro]

By the way. As I said it's easy to retouch. But If you allow me, I have another question about micro bevel.
Many people is worry about burr and don't want waste stock reaching it. But these same people stay wondering about micro. Micro bevel or in the case the back bevel is done by removing a lot of material at low angles to improve and make easy the cut. Then you apply the micro bevel to hold the edge.
My sister ask me if I could sharp some of her kitchen knifes. I have a Zwillinger chefs that came with 20dps and as I know my sister will cut lettuce and chop chicken with same knife so I did it with 20dps.
In this case if you want slice a thin slice of tomato or salami, low angles with micro is the best, but you can't use the same knife to chopp chicken as my sister do. Is my thinking about it correct?

 

[HeavyHanded]

I normally finish a freshly sharpened edge with a micro or by stropping, sometimes both.

Personally I do not see much benefit unless the microbevel surface is finer than the last stone used to shape the cutting bevel, preferably much finer. In that case it tends to make a thinner edge across even though the terminal angle might be a bit larger - it will cut just as well, last just as long as a single bevel (might be more durable but I haven't been able to verify this), and is somewhat faster to reliably create a clean apex. It also allows somewhat greater customization of the final edge finish. Just a few passes with a finer hone at least 2 degrees greater angle.

If you're touching up on a single stone, I'd say don't bother. It seldom produces a "better" edge by itself on most steel - is more of a finishing technique, one of several. A single bevel takes a little more QC.

 

[brasileiro]

Another view about microbevel is that the edge/bevel thickness on micro (shoulder to shoulder thickness) when using 10dps become thin if you put on it a 20dps microbevel. I own a Zwillinger chefs knife and is FFG. The blade angle is about 2,3 degrees inclusive. The bevel is 18,85 dps discounting the blade angle. The thickness of bevel at shoulder is about 0,026" or 0,67mm. Thin enough to slice anything easily. But let's exaggerate just to make easy to understand and imagine a very used FFG blade which the bevel almost on the spine of the blade or in middle of the blade, a 0,118" or 3mm thick blade at spine. In this scenario I guess is even 15dps will make the slicing job harder. So after some reads my guess is microbevel is about make the slicing job easily. My feelings is that when the bevel thickness is about 0,040" or 1mm is time to use a micro. But if you plan chopp with this knife, so probably 0,040" shouldn't be the best thickness for the job.

I don't have a computer close to me right now, so, sorry about the draw.

 

[awestib]

I normally finish a freshly sharpened edge with a micro or by stropping, sometimes both.

Personally I do not see much benefit unless the microbevel surface is finer than the last stone used to shape the cutting bevel, preferably much finer. In that case it tends to make a thinner edge across even though the terminal angle might be a bit larger - it will cut just as well, last just as long as a single bevel (might be more durable but I haven't been able to verify this), and is somewhat faster to reliably create a clean apex. It also allows somewhat greater customization of the final edge finish. Just a few passes with a finer hone at least 2 degrees greater angle.

If you're touching up on a single stone, I'd say don't bother. It seldom produces a "better" edge by itself on most steel - is more of a finishing technique, one of several. A single bevel takes a little more QC.

I am with Martin here too! I use a microbevel with a finer stone to bring up the refinement without heaving to polish the whole bevel. I do use increased finishing angles to get rid of a stubborn burr but short overlapping edge leading strokes take care of the burr for the most part and then I know better "where I am", if that makes sense. The other thing is that if I use a microbevel to clean up the apex/burr, I am not sure whether I actually created another new burr. Even if I use superlight strokes, I have in the past created a new burr - maybe if the stone was a hard one, no slurry, etc. but it happened on a good 1000 Chosera as well. The chosera is not super muddy but not "super dry" either so I don't know. I guess my technique sucks, that what it comes down to ...

One more thing I'd like to mention. You mentioned the 30 dps slot on the Sharpmaker. There was a time when some of us used a wooden dowel to scrape the apex sideways to reveal a burr and "brush" it all to one side in order to cut if off at the original bevel. I got that idea initially from Martina and Luong. Well, I noticed for some time that the kitchen knives I sharpened on the Sharpmaker for my family always had a "burr" next day after use (god knows how they were used though ...). Eventually I used the "wooden dowel trick" on a freshly sharpened kitchen knife on the Sharpmaker and guess what - there was a burr. So, just relying on light alternating strokes on the ceramic rods was no guarantie for a burr free apex. What Martin mentions on his Washboard with plain paper and increasing the angle a bit is pretty much the same principal with some possibility of burnishing as well - revealing a burr.
Sorry for the rambling ...

 

[FortyTwoBlades]

I like a 10° relief bevel with 15° micro, with the micro being applied using an ultra-fine stone.

 

[awestib]

I like a 10° relief bevel with 15° micro, with the micro being applied using an ultra-fine stone.

I like that too - the preparation of the 10 dps bevel just has to be right (e.g. fine enough) for the upcoming refinement IMO. If not, I have trouble with exact repeated strokes at the higher level due to literally no feedback. It's not only that though. I believe that even some higher grit stones do not prepare the apex well enough - kind of the polish is good enough but the apex still too "thick" to be abraded by a fine stone - again not sure, maybe it's my poor technique.

 

[FortyTwoBlades]

Fine stones that produce an abundant slurry can cause issues with that if you finish using edge-leading strokes. The loose abrasive plows into the apex, and blunts it a bit, though it also cuts off any burr. If apexing on such a stone or using it prior to apexing on a finer stone, use edge-trailing strokes as if you were stropping it.

 

[brasileiro]

...Sharpening at a more acute angle will naturally thin the edge more, over time; these thinner edges are inherently easier and quicker to touch up 'as is', without having to microbevel. There's also no need to remove more steel than necessary, touching up edges done this way...


David

Hey David. I didn't understood. My English is not so good. What do you mean with "thinner edges are inherently easier and quicker to touch up 'as is', without having to microbevel."
When you work on more accute edge does not create more area to work on?

 

[HeavyHanded]

I like that too - the preparation of the 10 dps bevel just has to be right (e.g. fine enough) for the upcoming refinement IMO. If not, I have trouble with exact repeated strokes at the higher level due to literally no feedback. It's not only that though. I believe that even some higher grit stones do not prepare the apex well enough - kind of the polish is good enough but the apex still too "thick" to be abraded by a fine stone - again not sure, maybe it's my poor technique.

I usually feel out the established bevel with a few light passes and then elevate the spine a little. This gets me on the microbevel pretty reliably when I want to come back to it after doing visual QC. I started doing it like this on all my plane irons and chisels and it works great on them - a little more challenging on bellies.

 

[Obsessed with Edges]

Hey David. I didn't understood. My English is not so good. What do you mean with "thinner edges are inherently easier and quicker to touch up 'as is', without having to microbevel."
When you work on more accute edge does not create more area to work on?

The context in which I referred to 'thinner edges' meant to convey something like:

'Thinner edges' = more acute angle = wider bevels

Meaning, wider bevels resulting from sharpening at a somewhat lower edge angle are easier to feel in flush contact on the hone.

Hope that clarifies what I was trying to say.

There's sort of a secondary advantage as well, in that the thinner the edge becomes, the less steel needs removing from the edge, to keep it very sharp.


David

 

[singularity35]

If you use a sharpmaker and hitting the edge, you are probably starting out with a microbevel. If you continue to use that angle, you will probably eventually end up with a macrobevel(one that can be seen easily?). Then if you keep using that angle, you will eventually rebevel the knife at the angle you are sharpening at.