KME sharpening help. Fine scratches up the blade.

[coltc11]

I've been having an issue lately when sharpening some of my knives. These are all just user knives, nothing special but I'd like to figure out what's causing it.

I'm getting very fine scratches along my sharpening pattern, sometimes up to .25" up the blade from the edge.

Any idea what causes that?

I figured it was the sharpening dust (blade material or diamond mater from the stones) causing the scratches but I don't see how or why they are causing the scratches that far up the blade away from the edge.

That being said, I am a bit amazed at the edge I got on the knife I sharpened tonight. Didn't mean to get as shinny as I did.

After I got done with the 1500 grit diamond, I flipped the stone over, wrapped a couple layers of that brown filling paper that comes in some packages around it, smeared a small amount of old Mothers polish on it and had at it. Finished up with clean paper. Came out a lot shinnier than I thought it would have. As you can tell, I still need some practice and could pay better attention to the heal.

If you zoom in, you can see some of the scratches I'm talking about.

 

[darth_cholo]

you gonna have to circle or highlight the scratches cause I can't see nothin.

 

[coltc11]

Hopefully they are more visible here. They are the vertical lines circled. Very fine scratches north of the edge. They were not there prior to me sharpening. I have sharpened other knives with no issues so it has to be related to something I did here. I did re-profile more here than I normally do.

 

[coltc11]

Here they are. I had to get the lighting just right and camera at the right angle.

 

[Roikyou]

What stone and how old was the stone?

Most new stones will do this until broke in, I've seen it the worse with the 50 grit. Don't let anything build up on the blade, clean up the metal and diamonds as often as possible to avoid dragging along the blade. Careful using the blades you really care about in the beginning. That's my experience so far. Once they break in, you don't see it as much but I still try to avoid to much build up. But once they break in, they're not as aggressive. I've seen in the beginning, they cut really fast but you have the potential for those scratch's. But over time they're more mellow and take more time to re-profile. I'm only at a little over three months, so it's pretty fresh for myself, the learning and breaking in experience.

 

[coltc11]

What stone and how old was the stone?

Most new stones will do this until broke in, I've seen it the worse with the 50 grit. Don't let anything build up on the blade, clean up the metal and diamonds as often as possible to avoid dragging along the blade. Careful using the blades you really care about in the beginning. That's my experience so far. Once they break in, you don't see it as much but I still try to avoid to much build up. But once they break in, they're not as aggressive. I've seen in the beginning, they cut really fast but you have the potential for those scratch's. But over time they're more mellow and take more time to re-profile. I'm only at a little over three months, so it's pretty fresh for myself, the learning and breaking in experience.

It was mainly with the 50 grit and I was taking quite a bit of material off. I wasn't keeping it clean or even attempting to. I figured it was due to all the dust on the blade while sharpening.

I'll have to try to be a bit more careful when taking a bunch of material off.

Thanks!

 

[Roikyou]

Great stone, cuts fast but leaves diamonds in the beginning. Then it's slower but doesn't leave the diamonds as often. One of the few pitfalls of the KME with the blade sideways, it's easier to build up "swarf" which you don't want on diamonds but do want on chosera stones. I personally like the horizontal blade, you can see the progress.

 

[aleforme]

Not really familiar with the KME and it's specific workings but is it possible you're letting the end of the stones go past the bevel? In other words, you're pushing or pulling the stone to far and the end edge is scratching the blade above the bevel. I had an old GATCO sharpener years ago and I would let the end of the stone run off the bevel. Scratched the hell out of a couple knives.

Sorry for the crude drawing.

 

[coltc11]

Not really familiar with the KME and it's specific workings but is it possible you're letting the end of the stones go past the bevel? In other words, you're pushing or pulling the stone to far and the end edge is scratching the blade above the bevel. I had an old GATCO sharpener years ago and I would let the end of the stone run off the bevel. Scratched the hell out of a couple knives.

Sorry for the crude drawing.

That's very possible. Combine that with all the diamond dust sitting on the blade and that would probably do it.

Now I'll see what I can do to clean these up a bit.

 

[Roikyou]

I worked with a few of my knives, very confident I've never ran the stone over the blade and still got those scratch's when the stone was new. Funny thing, you can get one or two scratch s, it could be in different locations across the blade. Unless your consistently running the one inch stone off the blade or over the blade across the length of the blade consistently, I can't see that being an issue.

I can also lightly see the scratch's along the full length of the blade, more so in some areas.

 

[tomhosang]

I had this exact issue with my KME when I first got it. I was running the edge of the stone past the bevel and scratching the blade. i'd be willing to bet that's what you're doing. I honestly didn't even feel it. Buy the guide rod stop and set it up so you can't do it anymore and all your headaches will be solved!

 

[Roikyou]

I'll keep an eye out for my blades also, make sure I don't see them. I still use the 50 quite a bit and especially with new knives. The 50 grit I really pay attention to build up on the blade. I do have the guide rod stop but never got the hang of using it. Maybe I'll give it a try again. Always trying to improve.

 

[Mo2]

You can also try and tape the knives but that diamond will eat the tape regardless. But it may help. Painters tape and or packing tape (or both lol)

For a stopper I took a cap from a bottle and put a cross cut into it and slid the rod end into it once it's mounted on the kme. It does an alright job of keeping the rod going past it.

Make sure your clamp is on the flat portion of the blade. If the blade has no flat one side is going to be a different angle than the other and this may cause one side to get scratches over the other. My solution for this was to get an edge pro lol but others have no issues with it.

Also wear the stones in with cheaper knives before using them on the expensive knives. Maybe 8 knives or something. Don't use excessive force, let the diamond do the cutting not the force. You'll wear them out fast as I did this on one of my kme stones when I first got it.

Also I generally apply some water or windex every few mins and don't wipe the swarf off because wiping it could scratch it. A spray bottle helps.

If no ones mentioned it before don't apex with the 50 grit stone. It's great for reprofiling and setting the angle and removing the material fast but it leaves a ragged edge and will cause edge issues later in use.

 

[Roikyou]

I use mineral oil on mine with the gold hones. I do wipe the swarf off, guessing best if you did to wipe to the blade, instead of across.

Question for you Mo2 When you apex with the 50 grit, your basically setting the angle then moving to the 100 or 140? So, mark the bevel, remove the marker, repeat on both side, then move up in stones to create the burr?

 

[Lapedog]

I've been having an issue lately when sharpening some of my knives. These are all just user knives, nothing special but I'd like to figure out what's causing it.

I'm getting very fine scratches along my sharpening pattern, sometimes up to .25" up the blade from the edge.

Any idea what causes that?

I figured it was the sharpening dust (blade material or diamond mater from the stones) causing the scratches but I don't see how or why they are causing the scratches that far up the blade away from the edge.

That being said, I am a bit amazed at the edge I got on the knife I sharpened tonight. Didn't mean to get as shinny as I did.

After I got done with the 1500 grit diamond, I flipped the stone over, wrapped a couple layers of that brown filling paper that comes in some packages around it, smeared a small amount of old Mothers polish on it and had at it. Finished up with clean paper. Came out a lot shinnier than I thought it would have. As you can tell, I still need some practice and could pay better attention to the heal.

If you zoom in, you can see some of the scratches I'm talking about.

View attachment 880792

Are the stones new? The scratches are likely from using newer diamond stones that have not been broken in. As you use the new diamond stones little diamond particles break off which are ultra hard and will scratch the blade if you aren’t aware to either blow them away or vaccum them up.

I recommend you put some water mixed with dish soap on your diamond stones. Not only will it make the action smoother when sharpening but it will capture the diamond dust particles and prevent them from scratching up the blade.

 

[coltc11]

Lots of great tips here. I'm going to sharpen another one later today and I'll give these suggestions a try.

 

[Lapedog]

I use mineral oil on mine with the gold hones. I do wipe the swarf off, guessing best if you did to wipe to the blade, instead of across.

Question for you Mo2 When you apex with the 50 grit, your basically setting the angle then moving to the 100 or 140? So, mark the bevel, remove the marker, repeat on both side, then move up in stones to create the burr?

Don’t bother trying to find an alex with 50 grit. You will eat away alot of the steel without ever getting it. 50 is too low a grit for getting a real apex. At 100 or 140 you should start checking for an apex.

 

[Mo2]

I use mineral oil on mine with the gold hones. I do wipe the swarf off, guessing best if you did to wipe to the blade, instead of across.

Question for you Mo2 When you apex with the 50 grit, your basically setting the angle then moving to the 100 or 140? So, mark the bevel, remove the marker, repeat on both side, then move up in stones to create the burr?

Pretty much what lapedog said. Tho id start to get a burr with the 140 not 100. but that's just me.

 

[Roikyou]

So setting your angle depending on how extreme is where your 50/100 is at. The apex is where the edges comes together but the burr should form when the edges come together. If the angle is set, you can just stick with the 140. Am I over reading where if you find the apex, your bound to find the burr. Once your get the burr, you do your best to avoid the burr for further grits. (300 on)

 

[Mo2]

So setting your angle depending on how extreme is where your 50/100 is at. The apex is where the edges comes together but the burr should form when the edges come together. If the angle is set, you can just stick with the 140. Am I over reading where if you find the apex, your bound to find the burr. Once your get the burr, you do your best to avoid the burr for further grits. (300 on)

Looks good. You'll likely always get a bur just keep it small as possible.

As for a mirror polished edge, Focus on scratch patterns. Ie make sure you remove the previous stones pattern before continuing. I like to do this by changing the direction of the scratch pattern. one direction on one stone and get uniform pattern then do up and down with the next, so your alternating the scratch pattern to verify the previous pattern is out. Then when you strop you get out most of the scratches (tho you'll likely never remove all the scratches but a majority of them). Focusing on that will make a more uniform result. Juggle this with bur formation can be hard for some.

Hope it helps. A loup or magnifying glass help alot here.