Can't get Sebenzas sharp with Sharpmaker

I sharpened my benchmade for years on a sharpmaker. Got as good as I could at it. Was never happy with the steel/knife. Had to sharpen it most days. I eventually moved to a dmt aligner system, diamond lansky essentially, and got markedly better results instantly from it. By results I mean a longer lasting edge. I still have my sharpmaker, I reserve it for odd shape blades I can't sharpen on my dmt. I would recommend trying a dmt aligner or maybe try sharpening by hand. Diamonds If it's got vanadium. Which also is a part of why my results were subpar with the sharpmaker I believe. Using ceramic rods on s30v.
 
jjg6319 said:
Based on your picture you are not getting to the Apex.

Are you using the 40 degree slots so it would be a 20 bevel? That is what I use not the 30 for 15. You could get some CBN rods as that would be quicker to profile the edge, but at this point maybe you don't want to invest more in sharpening the CRKs.

I have used the sharpmaker at 40 setting and had good results. Try cutting phone book paper before you start and check the knife between changing rods to see if you are improving the edge.

Do you follow the instructions of starting on the edge of rod and then go to the flats for 20 strokes for each alternating rods?

Clean your rods with Ajax or Bar Keepers Friend to make sure they are clean. This would speed up your sharpening progress.

Your knife is a tanto blade so the grind is straight and you don't have a belly to contend with. That should make your sharpening easier.

Watch the videos in this post:

P

Thread 'Factory edge or sharpen?'

Just curious how many crk owners keep your factory edge as long as you can then send it out to factory for a sharpen ?
How many just say F it and sharpen themselves ?

I have a few CRK’s now I’m on the fence about sharpening. I use my wicked edge on all my other knives with great results but something about touching my reeve edges makes me cringe
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I do 40. Last night I tried sharpening it again by angling the blade away from the rod a little broader than straight up and down to get to the apex and was actually able to get it sharp again.
 
bmo419 said:
Yeah definitely not hitting the apex based on that photo, looks much closer to the shoulder. So it would make sense if the factory edge is pretty high on that particular CRK especially if you were using the 40 degree (inclusive) slots on the Sharpmaker in that photo. Spyderco's folding knives generally have a ~17dps edge so would work fine with the 40 inclusive (20dps) slots and why you don't have issue sharpening those.

You got a few options. First would be reprofiling the CRK to a lower angle with the diamond or CBN rods. Having done this in the past before I learned to freehand, this will take awhile on the Sharpmaker. You could get a different sharpening system that can accommodate the CRK sharpening angle. Or if you know someone with a 3D printer, there's printable blocks out there with many different angles for the Sharpmaker rods way beyond the standard 15/20dps.
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I think I'm going to make a point to hold the knife slightly broader like I've mentioned so it gets to the apex and see if that's adequate for me. I used it today several times after doing that last night and it performed satisfactorily. I have a set of the Sharpmaker diamond rods too so maybe if I'm feeling ambitious one day I'll see about taking that convex bevel down to a regular 40.
 
Crag the Brewer said:
Yeah, it "looks" thick behind the edge?
Are these thicker knives?
From the picture, id want a shallower sharpening angle. Although I like less than 15 degrees secondary.
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They're actually pretty thin BTE, and will get slightly thinner as it gets sharpened the first couple of times due to the way CRK do their hollow grinds. Unfortunately their factory sharpening is very lacking in my experience. Both my Inkosi and 31 were really convexed and even dull towards the tip. The 31 had 2-3mm of its tip completely unsharpened to the apex, but was otherwise well polished giving the appearance of sharp but not even close. Really disappointing to see cut corners like that on an otherwise perfectly made knife.
 
sailfish said:
I think I'm going to make a point to hold the knife slightly broader like I've mentioned so it gets to the apex and see if that's adequate for me. I used it today several times after doing that last night and it performed satisfactorily. I have a set of the Sharpmaker diamond rods too so maybe if I'm feeling ambitious one day I'll see about taking that convex bevel down to a regular 40.
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I would reprofile the bevel to 30 degrees with the diamond rod then microbevel with 40 and everytime you sharpen use 40 and you'll hit the apex. I think trying to hold a different angle than straight vertical with the knife will defeat the idea of the sharpmaker and be highly inconsistent. I guess I'm saying that resetting the bevel sounds like the answer. But the shaprmakers not fast, so I'd rather rebevel at 30 and only sharpen the mictobevel at 40.

I have done this on some of my knives using a chefs choice to do the heavy lifting of reprofiling the entire blade to 30 then I upkeep on the sharpmaker at 40. Just be careful not to round the tip off with a chefs choice
 
I am a big fan of the Sharpmaker, especially for someone new to sharpening knives. It is a good system to start with but it does have its limitations. The diamond or CBN rods would go a long way with helping you to reproduce the edge. I have moved onto benchstones, partly for the challenge and partly for the versatility they offer me. I still think if the OP picked up a set of diamond rods he could reprofile that edge on his Sharpmaker.
 
Several factors at work here but the primary factor is of course that you're not hitting the apex and to work with the Sharpmaker you'd need to reset the bevel geometry so that the angle at the apex was equal to or less than the angle of the Sharpmaker. The other is that sintered ceramics do tend to have the surface grains blunt with time and as such need periodic reconditioning to expose fresh grains so they're actually cutting instead of rubbing. If the grains are blunted you're basically just getting a steeling effect. Lastly, the steel type you're using is not going to respond well to alumina ceramic--diamond or CBN will be more appropriate. The Sharpmaker ceramic rods can be used for light touchups but shouldn't be used for bevel shaping or maintenance--only finishing. They are not hard enough to cut the vanadium carbides in the steel, which are present in large enough quantities to cause some issues despite their very small (~1µm) size.
 
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