Advice wanted - Sebenza 31 + Sharpmaker

[carmant]

Hi!

Relative newbie to sharpening - and I am really struggling to get a sharp edge on my small Sebenza 31.

I am using a Sharpmaker, which I have used to sharpen my other knives. I have a a SAK (not sure what steel), Spyderco PM2 (S30V) and Spyderco Ladybug (K390), and have successfully managed to get them to hair shaving sharp with relative easy. My general process is use the standard brown ceramic, white ceramic, and then finally strop. I have watched all the various Youtube videos, and use the sharpie method for all knives so I can see where I am making contact with the blade. This has worked really well with all the other knives.

But with the Sebenza 31 I have spent probably about 1hr+ trying to get a good edge but its still not sharp. I’m a bit worried that I have started to accidentally re-profile it? I know the Sebenzas have the convex edge and maybe my technique with the Sharpmaker has interfered with that? If thats the case, should I just continue to make slow and steady progress with the sharpmaker, in the hope it gets there eventually? Or should I try something else? I live in UK, so sending to CRK to get sharpened would be a real pain.

It’s also not as if the Sebenza was completely blunt before I started - <1 year old, and has seen relatively light use - boxes, cardboard, plastic packaging etc etc.

Any advice would be really welcome!

 

[King of the Cheese]

I have found through owning CRKs, Spydercos, and a sharpmaker used to sharpen both that it is more an “expectations” issue for myself. I have come to terms with the fact that the geometry of the blades and edges at Spyderco are conducive to maximum cutting performance. In other words, in the “edge” world, nothing beats a spyderco… seriously. My Spydercos make ribbons out of copy paper like it’s nothing. CRK makes a great knife, but I don’t expect them to cut like say my PM2 with a razor sharp edge. It just won’t happen. Both cut up cardboard just fine. Since I don’t use my knives to cut phonebook paper all day, it works just fine for me.

 

[willc]

Hi!

Relative newbie to sharpening - and I am really struggling to get a sharp edge on my small Sebenza 31.

I am using a Sharpmaker, which I have used to sharpen my other knives. I have a a SAK (not sure what steel), Spyderco PM2 (S30V) and Spyderco Ladybug (K390), and have successfully managed to get them to hair shaving sharp with relative easy. My general process is use the standard brown ceramic, white ceramic, and then finally strop. I have watched all the various Youtube videos, and use the sharpie method for all knives so I can see where I am making contact with the blade. This has worked really well with all the other knives.

But with the Sebenza 31 I have spent probably about 1hr+ trying to get a good edge but its still not sharp. I’m a bit worried that I have started to accidentally re-profile it? I know the Sebenzas have the convex edge and maybe my technique with the Sharpmaker has interfered with that? If thats the case, should I just continue to make slow and steady progress with the sharpmaker, in the hope it gets there eventually? Or should I try something else? I live in UK, so sending to CRK to get sharpened would be a real pain.

It’s also not as if the Sebenza was completely blunt before I started - <1 year old, and has seen relatively light use - boxes, cardboard, plastic packaging etc etc.

Any advice would be really welcome!

Get some good lighting and magnification and inspect the edge to see exactly where you are hitting with the rods.

Most likely the angle is slightly off and you are not hitting the apex.

Instead of going straight up and down slightly adjust your angle so you will hit the apex.
You may end up with a micro bevel but that is fine, what you want is sharp.

Take it slow.
Couple swipes, check it and rinse repeat.
Once you start feeling a burr lighten pressure and maybe try edge trailing from there on out.

It is easy to get frustrated cause you are getting good results and a couple errant passes and it now feels dull.
Don’t worry if a couple passes can mess up the edge usually just a few more on point passes with fix it right up.

Again inspect the edge, you gotta be able to see exactly what you are doing and what you WANT to do.
Also keep pressure light, I am way guilty of too much pressure.

Good luck.

 

[carmant]

I have found through owning CRKs, Spydercos, and a sharpmaker used to sharpen both that it is more an “expectations” issue for myself. I have come to terms with the fact that the geometry of the blades and edges at Spyderco are conducive to maximum cutting performance. In other words, in the “edge” world, nothing beats a spyderco… seriously. My Spydercos make ribbons out of copy paper like it’s nothing. CRK makes a great knife, but I don’t expect them to cut like say my PM2 with a razor sharp edge. It just won’t happen. Both cut up cardboard just fine. Since I don’t use my knives to cut phonebook paper all day, it works just fine for me.

Thanks for this, what you‘ve said makes a ton of sense. Objectively, the CRK Sebenza 31 is probably actually quite sharp, but it just doesn’t cut ribbons of thin paper like the Spyderco PM2 does - and I have been using that as a “test” of sharpness. Even just by looking and feeling the blades, you can tell the Spyderco ones seem to be much thinner / ”slicier” (I’m sure there’s more correct terminology for that!). It’s definitely worth remembering that being able to cut thin bits of paper is not the only metric of a good utility pocket knife!

Get some good lighting and magnification and inspect the edge to see exactly where you are hitting with the rods.

Most likely the angle is slightly off and you are not hitting the apex.

Instead of going straight up and down slightly adjust your angle so you will hit the apex.
You may end up with a micro bevel but that is fine, what you want is sharp.

Take it slow.
Couple swipes, check it and rinse repeat.
Once you start feeling a burr lighten pressure and maybe try edge trailing from there on out.

It is easy to get frustrated cause you are getting good results and a couple errant passes and it now feels dull.
Don’t worry if a couple passes can mess up the edge usually just a few more on point passes with fix it right up.

Again inspect the edge, you gotta be able to see exactly what you are doing and what you WANT to do.
Also keep pressure light, I am way guilty of too much pressure.

Good luck.

Thanks for these tips - again some really helpful advice. I’ll give it a rest for today, but will come back to it tomorrow and try and apply some of these tips. I think you could be right about the angle, towards the end of the sharpening attempt I did this morning, and I started adjusting the angle outward slightly, and I think I was starting to get better results. Also i probably definitely need to lighten up the pressure. It’s easy to think more pressure = more results, but I think im learning its much more about technique, and being consistent.


Thank you both!

 

[willc]

You will get it.
Setting things aside when things are not going great is a very smart thing also.

I have had blades that were beating me down and when I set them down and went back to it the next day with a fresh set of eyes the sharpening would go so much smoother.

Also know that the Sharpmaker is an excellent tool and it is completely capable of giving insane edges.
Really the only thing you may want to add at this point is some sort of strop to clean up the burr and refinement.

There is a ton of great information here in this forum and others way more knowledgeable that can help if you need it down the road.

 

[Obsessed with Edges]

Best way to get the edge cutting well quickly (or somewhat quicker on the SM), is to utilize the optional diamond or cbn rods to thin out the edge. The brown ceramic by itself will take an extremely long time to get that done.

I have an older Sebenza in S30V. I had the same initial impression of the edge. It was nicely done, but not as wickedly slicey as I would prefer. Everything changed for the better after I reset the edge a few degrees narrower, using diamond rods on a similar V-crock device. And that didn't take awfully long - maybe 45 minutes, as opposed to the many, many hours' work needed to do that with a brown/grey ceramic.

 

[c7m2p3]

I can speak to my own experience. For whatever reason, my Sebenza 31 delivered a few months ago had a very small edge bevel which was rather obtuse, I would estimate well over 40 degrees inclusive which is the most obtuse standard angle offered by the sharpmaker. The extremely thin edge bevel it came with would have been hard to accurately gauge where the material was coming off without maginifcatino if I was trying to do it by eye.

I would up reprofiling mine anyways since I have no intention of selling it and I wanted it to cut like a demon to use that thin hollow grind. I am happy with the results.

I would go grab a cheap jewlers loop from a sewing or hard wear store and see if that helps you identify where exactly the ceramic is hitting on that edge bevel.