Been sharpening 8Cr13MoV on Sharpmaker for 2 hours

00ChevyScott

00ChevyScott

Basic Member
Joined
Dec 3, 2010
Messages
2,678
and it's still not sharp. The entire edge looks pretty polished now, and I've done the sharpee trick on the edge to make sure I'm hitting it and I am for the most part. What am I doing wrong? I am using the 40deg side.
 
I can take my finger nail and slide it down the bevel and it doesn't really catch on either side. Maybe a little more on the "right side" of the blade since it's harder to see that side of the blade when you're sharpening it (right handed).
 
Take a look with some magnification (~10X or better, if you have it), under bright light. It's pretty easy to miss the black ink sometimes. More than once, I've seen a hair-thin 'stripe' of black marker at the very edge, which wouldn't otherwise be visible by the naked eye. Looking with the magnifier will reveal other possible issues too.
 
Huh, now that's just plain odd. If you're all the way down to the edge, it SHOULD be shaving at this point off the mediums. I might be tempted to actually deliberately tilt the blade into the stone a bit more, try for just a HAIR more angle (41 or so) and make a couple ultra-light passes, with as little pressure as I possibly could. If it gets notably sharper after that, you knocked off a fine wire edge.

About the only reason I could think of would be either too much pressure rolling the edge, or a burr flopping back and forth. If you have a strop, a few passes there might be useful as well, just to see.
 
00ChevyScott said:
I can take my finger nail and slide it down the bevel and it doesn't really catch on either side. Maybe a little more on the "right side" of the blade since it's harder to see that side of the blade when you're sharpening it (right handed).
Click to expand...

The other possibility is that the edge isn't yet apexed. If no (apparent) burr is present on either side, it can only mean one of three things: 1.) The edge isn't completely & cleanly apexed, or 2.) The edge has inadvertently been rounded off by inconsistent angle control, or 3.) The edge IS apexed and pure, in which case it will also be very sharp.

A wire edge can be very sharp, and if it just happens to be perfectly straight (not folded to either side), it can mimic a sharp edge under very light cutting. But it usually folds over very quickly. Making a few cuts into something tougher, like wood or heavy cardboard, will usually make it fold one way or the other.

I'll re-emphasize my earlier recommendation to check with magnification. If the edge isn't apexed or if it's rounded off, that should be easy to see when viewed under good magnification & good light.
 
I'll throw in this one additional thing.

Two full hours on the Sharpmaker would wear ME out. My hands, neck and back would all be tired and sore. Fatigue is never a good thing at all, when sharpening knives. Angle control and pressure control both go out the window, for me, if I try to stay at it that long. So it may be worthwhile to just lay everything down for a bit, and find something restful and relaxing to do. Have a good meal. Keep thinking about it, if you like, but give the hands a rest. Maybe just sit back and examine that edge with a magnifier, but give yourself at least a few hours away from the rest of the gear. It'll pay off when you come back fresh & energized. :)
 
Obsessed with Edges said:
I'll throw in this one additional thing.

Two full hours on the Sharpmaker would wear ME out. My hands, neck and back would all be tired and sore. Fatigue is never a good thing at all, when sharpening knives. Angle control and pressure control both go out the window, for me, if I try to stay at it that long. So it may be worthwhile to just lay everything down for a bit, and find something restful and relaxing to do. Have a good meal. Keep thinking about it, if you like, but give the hands a rest. Maybe just sit back and examine that edge with a magnifier, but give yourself at least a few hours away from the rest of the gear. It'll pay off when you come back fresh & energized. :)
Click to expand...

This is often overlooked but sound advice. Kind of like studying ..
 
I think angle control may be the culprit. I'm definitely a novice when it comes to sharpening. I managed to make decent working edge with the medium stones but it seems like using the fine stones on this knife only dulls it. I guess I just need a lot more practice.

I got an Izula really sharp (1095 steel), is 1095 easier to sharpen that 8Cr13MoV?
 
00ChevyScott said:
I think angle control may be the culprit. I'm definitely a novice when it comes to sharpening. I managed to make decent working edge with the medium stones but it seems like using the fine stones on this knife only dulls it. I guess I just need a lot more practice.

I got an Izula really sharp (1095 steel), is 1095 easier to sharpen that 8Cr13MoV?
Click to expand...

1095 can be easier, sometimes. Stainless steels are sometimes just a little more difficult, for different reasons. The different alloys might be more abrasion-resistant (carbides in them make it harder to file/abrade metal away), or more ductile (very stubborn, difficult-to-remove wire edges & burrs). On the other hand, 1095 can sometimes be difficult to get a clean edge on, especially with diamond hones. Diamond can scrub the burr off of 1095 in a single pass, which if overlooked, can make it seem as if the burr never forms.
 
00ChevyScott said:
I think angle control may be the culprit. I'm definitely a novice when it comes to sharpening. I managed to make decent working edge with the medium stones but it seems like using the fine stones on this knife only dulls it. I guess I just need a lot more practice.

I got an Izula really sharp (1095 steel), is 1095 easier to sharpen that 8Cr13MoV?
Click to expand...

To me it sounds like you have not set the bevel. Your edge should be very sharp after the medium ceramic and finer stones should never make a edge duller. Usually if you make a edge duller using a fine stone the bevel prior to using the fine stone was not complete or ready to be taken to the next level.

Even forming a burr does not always tell the story, you could have made a microbevel on one side by mistake forming a burr on the other then tried to progress to finer stones only to completely round off the edge. It's easier than you think especially if you were fatigued during your last sharpening.

1095 from ESEE is some of if not the best 1095 you will find in a production knife and though 1095 is a fairly easy steel to sharpen ESEE 1095 is the toughest to sharpen compared to other 1095 and rightfully more so than 8Cr. 8Cr is like AUS8. The izula probably had a better grind to start making sharpening much easier and with better results.
 
It took 2 weeks on cheap alum oxide 320 & 400 stone to sharpen my Navy k631. The factory angle was way too obtuse. Please note I was removing LOTS of steel. Navy is advertised as 440c, but I suspect it is 8C13MoV or 9C at best. My Enlan EL01 and 02 took less time (1 week) as the factory angle is thinner. It's about 1-2 hr per session (otherwise I got too tired), not every day, but more often than not, i.e. 2 out of 3 days (can't remember clearly).

Finishing is on 1000 grit synthetic waterstone, then 1000 grit sandpaper stropping on cardboard with MAAS Metal polish.

Once I got it to where I want, touching up is 5 - 10 mins job on 1000 grit sandpaper followed with stropping.

If it takes that long for you, I guess it isn't apexed properly. However, at 40, you should get it sooner (I was making 25-30). What knife it is?

You can check out the result on the sanrenmu thread under review & testing subforum.
 
Last edited:
To add more, any of the 8Cr13MoV I sharpened, does form burr and quite stubborn, especially at lower angle. 40 shouldn't be a problem though. Now, I keep microbevel at about 40 to prevent roll & chips.

As said, relax & meditative is the correct state of mind & body in sharpening session.
 
I got so tired of going through this. My sharpening skills just suck. I use my sharpmaker to keep sharp knives sharp but don't go near it if the blade is dull. Just got a 2 sided water stone and have made some strides with it, but, I just got the work sharp and it can put an edge on my knives in about 2 minutes. It is absolutely stupid proof for me.
 
knifenut1013 said:
To me it sounds like you have not set the bevel. Your edge should be very sharp after the medium ceramic and finer stones should never make a edge duller. Usually if you make a edge duller using a fine stone the bevel prior to using the fine stone was not complete or ready to be taken to the next level.

Even forming a burr does not always tell the story, you could have made a microbevel on one side by mistake forming a burr on the other then tried to progress to finer stones only to completely round off the edge. It's easier than you think especially if you were fatigued during your last sharpening.

1095 from ESEE is some of if not the best 1095 you will find in a production knife and though 1095 is a fairly easy steel to sharpen ESEE 1095 is the toughest to sharpen compared to other 1095 and rightfully more so than 8Cr. 8Cr is like AUS8. The izula probably had a better grind to start making sharpening much easier and with better results.
Click to expand...



I agree with this. I think you have not yet reached the TRUE apex of the edge. Only way to tell for sure is with magnification like already mentioned.

The stones aren't the problem. With a light touch I can get hair whittling edges with the brown ceramic alone. :)
 
If perfect bevels are NOT desired, you can pick up a cheap oil/water stone from a hardware stone and rough out a primary bevel in a couple minutes and save yourself the hassle of using a touch up sharpening kit for setting the bevel.

The advice is if you can't keep an even angle on the stone.
 
if you are putting a new angle on a knife, i would recommend a basic set from Lansky, if takes me like a half hour to reprofile my enlans to 20deg with the coarse stone.
 
You must log in or register to reply here.
Back
Top