How to sharpen knife with microbevel?

[FlaMtnBkr]

I am a bit confused about how to approach a micro bevel when sharpening a knife.

Say I sharpen a knife on an Edge Pro to 20 degrees inclusive. I then use a Sharp maker set on 30 degrees to maintain the edge. If I do a lot of work one day and really dull the knife what is the best way to sharpen it? Do I go to the Sharp maker and just go to town in the hope that the knife gets sharp? Or do I put the knife back on the Edge Pro set at 20 degrees and have to remove a substantial amount of steel to bring the edge back past the micro bevel that was put on?

I don't even have a sharp maker so this is somewhat of a hypothetical question but my knives do end up with a micro bevel between stropping and touching up an edge on a stone between trips to the Edge Pro. But when I have a micro bevel that I can see when reflecting light off the edge, and I work a knife hard, I am unsure of the best way to bring a really good edge back. If I put it on the Edge Pro and match the original angle, there is a lot of work involved to work up a burr. Plus my nice polished edge has to be re-worked and done over which is a lot of work just because I had to use a knife really hard and it got paper tearing dull.

So what does everyone do? I am guessing most work the microbevel with a more coarse stone and work through the grits until a sharp edge is achieved. If this is the case then how big do people let the micro bevel get before you take the knife back down to the original angle?

Thanks and sorry for the long post!

 

[rpttrsn]

I think that you answered part of the question.
"But when I have a micro bevel that I can see when reflecting light off the edge"
IMO I would just go to the micro bevel edge if its still visible to me and touch up this edge. Then test for sharpness.
This is one of the advantages in the Spyderco system. Quick touch up's to maintain your edge. This all depends on how hard I used the knife and what toll it took on the edge. I only go back to the Edge Pro when my touch up methods take too long.

 

[dipbait]

I dont know the correct answer. I put a microbevel on my knives , but I only take one or two very light swipes per side.It does not take me long to hone the micro bevel out the next time I sharpen.

 

[THG]

What you want to do is your choice. You have a couple options if you've got a 20° edge and are using a 30° microbevel:

1. Maintain the microbevel, i.e. continue using the 30° setting to sharpen your knife. You will eventually work your way up to an even double bevel (where the lengths of one angle is 50%, and the other is 50%, as opposed to 99%/1%), and then up to a single bevel again over time.

2. Use the Edge Pro again at 20°. You will have to grind down to the edge again. At that point, you can either do another 30° microbevel or maintain it at 20°.

 

[me2]

The point of a micro bevel is that its very small. If the microbevel gets big enough that a couple dozen strokes on the 204 wouldn't sharpen it, then I'd say its time to go back to the EP. I try not to let my micro bevels get much bigger than 1/64" wide. After that, it takes too long to get rid of them when having to do a full resharpening.

 

[HoosierQ]

I link scandi grinds with a micro bevel. I use a very fine (don't know the actual grit) ceramic rod and do maybe ten very light strokes per side...no pressure at all...maybe not even blade weight...just glide the blade down the rod with some of the handle weight counter balancing. Very happy with those results. You really have to hold the light just right to see it...but I want to be able to see it if the light is right.

I also micro (as a maintenance step) my flat ground kitchen knives. They have a very acute bevel and after I get to where steeling doesn't help, I'll stroke on a micro and that will keep it going for quite a while. After maybe 3 or 4 touch ups to the micro, I'll put a new bevel on with a stone and start over.

I am new to micro-beveling (as a consious act) so I am learning. YMMV.

 

[FlaMtnBkr]

I have been trying to get my Kershaw Volt with M390 steel sharp and have been sharpening it on my Edge Pro Apex. The micro bevel was not very big and could really only be seen by a change in light reflection and maybe about 2 sheets of notebook paper wide.

Using the 220 grit stone I have been sharpening for close to 30 minutes and still have not got a burr to develop. A lot of work to get it back sharp again after having a micro bevel. I stropped it a lot and used a Falkniven DC3 and could not get it back sharp after it got dull which is why I went back to the Edge Pro and have this question.

I am still curious what others do and what I should do as an alternative to using the Edge Pro.

I have another question that I will probably have to start a new thread about but will throw it out: Anyone know the website that sells different sharpening stones including a lot of triangle stones that will fit the Sharp maker? I have seen it mentioned a couple times here on Bladeforums but can't find anything with a search here or on Google.

 

[cbwx34]

If I understand your question... if you have a microbevel established, or you're going to put one in, you don't need to raise a burr with the secondary (lower) bevel. Just create the secondary bevel, get close to the edge, then put in the micro or primary bevel. To resharpen, you can maintain the primary bevel... occassionaly hitting the secondary bevel to keep it all lined up... basically narrowing the primary bevel when it gets too wide by touching up the secondary. An exception to the above is if there's major damage to the edge or its fatigued. But you don't necessarily have to sharpen a microbevel "out" just to put one back in.

Also the primary bevel need only be created with finer stones, not coarse ones. It doesn't require much metal removal.

cbw

 

[THG]

Using the 220 grit stone I have been sharpening for close to 30 minutes and still have not got a burr to develop. A lot of work to get it back sharp again after having a micro bevel. I stropped it a lot and used a Falkniven DC3 and could not get it back sharp after it got dull which is why I went back to the Edge Pro and have this question.

Once you get close to the edge, the process becomes very slow-going. When I'm using my Aligner to reprofile an edge, it starts out really fast cutting down the shoulder. But as I get closer to the edge, it takes a long, long time before it looks like I've put a dent in progressing any further. If I were to graph my progress, it would be an exponentially decaying function.

This is why I use a bench grinder for rebeveling, now. It takes about 10 seconds vs. 8-20 hours, and I mean that very literally.

If I understand your question... if you have a microbevel established, or you're going to put one in, you don't need to raise a burr with the secondary (lower) bevel.

I think he's trying to clear the microbevel and then put another one back on.

 

[FlaMtnBkr]

Thanks for the replies.

I am not sure what I'm doing to be honest. I was wondering what other people do when using micro bevels. I'm just not sure which to sharpen when I use a knife hard and get it really dull. I hear of people not being able to get a dull knife sharp when using a sharp maker. So if sharpening the micro bevel won't get the knife sharp then sharpening the edge (secondary?) bevel makes sense but can take a looong time. But the micro bevel can be sharpened to, I guess it just takes a coarse stone and will get less micro. Just not sure the best way to approach the problem.

I guess my plan will be to thin out an edge to whatever I want for performance and then sharpen at 30 degrees for a micro bevel and keep sharpening at 30 degrees until the micro bevel grows really big. Then thin out the edge again to get back some of the performance. Instead of trying to thin out the edge every time the knife gets dull and having to put a lot of work into a wide, acute edge bevel to keep the micro bevel really small.

Sorry if this is hard to follow and thanks again for the replies.

 

[HoosierQ]

Bench Grinder ? How do you a) keep from burning up the steel, and b) control the thing? Are you talking about a good old-fashioned everyday bench grinder or a belt grinder or what?

Not being nasty it's just I can't do much of anything with a bench grinder that doesn't end up smelling like welding...and that's too hot.

 

[dsmegst]

Thanks for the replies.

I am not sure what I'm doing to be honest. I was wondering what other people do when using micro bevels. I'm just not sure which to sharpen when I use a knife hard and get it really dull. I hear of people not being able to get a dull knife sharp when using a sharp maker. So if sharpening the micro bevel won't get the knife sharp then sharpening the edge (secondary?) bevel makes sense but can take a looong time. But the micro bevel can be sharpened to, I guess it just takes a coarse stone and will get less micro. Just not sure the best way to approach the problem.

I guess my plan will be to thin out an edge to whatever I want for performance and then sharpen at 30 degrees for a micro bevel and keep sharpening at 30 degrees until the micro bevel grows really big. Then thin out the edge again to get back some of the performance. Instead of trying to thin out the edge every time the knife gets dull and having to put a lot of work into a wide, acute edge bevel to keep the micro bevel really small.

Sorry if this is hard to follow and thanks again for the replies.

Before my paper wheels came along, micro-bevels allowed me to very quickly get a good edge w/o a full sharpening session. So I establish my edges at 30 degrees. Then for the next dozen or so times I needed to resharpen, I set my fine rods at 20 degrees and make a few swipes. That's usually enough to create a tiny micro-bevel. The next time I sharpen requires a few extra swipes. It takes a good number of resharpening sessions for the micro-bevel to grow big enough to start using the medium rods.

My main goal is to remove as little metal as possible while creating a new edge. The less I remove, the more times I can quickly refresh the edge w/o redoing the entire main bevel.

 

[THG]

Personally, I consider my edge "ruined" if I get a microbevel. It's hard to keep the angle on a microbevel when you sharpen by hand.

In my opinion, microbevels are difficult to control, so I don't use them.

 

[Jason B.]

I'm not much for micros either but it can make for quick touch-up and many less steps in sharpening.

A microbevel is just that, micro. If you can easily see it then its probably way to big and without doubt effecting cutting.

A microbevel should also only be set in place by a very fine abrasive. I find a spyderco UF SM rod works excellent for this task.

300grit grit seems to be a minimal stopping point before using such a method or the size of the back bevel scratch pattern will effect microbevel formation.

When setting a micro on quality steel don't be afraid to use very low back bevel angles. Ì like 10 per side with a 20 micro. Very strong and very sharp.

A big mistake in setting a micro is the use of a coarse stone to start it.

Using a UF ceramic start with medium pressure and careful angle control. Make one pass per side setting the micro, follow with about a hand full of passes per side with feather light pressure reducing the burr as much as possible. You can stop here but a few swipes on a strop never hurts.
The key will be pressure because of the small surface area you are working with. Too much pressure will cause over-deformation of the micro, this is especially enhanced because of the burnishing effects of the ceramic sharpeners. So easy does it.

 

[THG]

I'm not much for micros either but it can make for quick touch-up and many less steps in sharpening.

A microbevel is just that, micro. If you can easily see it then its probably way to big and without doubt effecting cutting.

A microbevel should also only be set in place by a very fine abrasive. I find a spyderco UF SM rod works excellent for this task.

I agree with this, and I'd like to add that you have to make sure you've reduced your burr as much as possible, or that you have polished your primary bevels enough that you have a sharp, single-bevel edge. Then use a stone as fine as possible to put on the microbevel.

Otherwise, you might just end up flopping a burr back and forth for a long time, especially if you're using ceramic (diamonds tend to break up the burr when putting on a microbevel, in my experience).

 

[HwangJino]

I use stones to sharpen and microbevel is only done with fine stone, I use 8000 grit and only a few passes. Anymore and you will set a new bevel.

When I look at my blade through a reflection my bevel looks almost flat but at the very edge you see light bending VERY slighty.

I always look down the edge (handle pointed to my face) to see bevel, sometimes my fingers are saturated eith stone and can't feel edge.

Basically when my microbevel is really good, I can cut thin magazine paper in a curve and it will make almost no sound and cut effortlessly. Any drag or one piece of fiber snag, and I start over.