# Scratch/Buffing marks on Knife after sharpening?



## Tnaquin35 (Jan 1, 2021)

Hey guys,
So I was sharpening a Shun Classic Chef's knife for my Sous Chef last night and after running it on my 1k, I noticed some odd spots on the side of the blade that looked like it was hit with a buffing wheel. I obviously didn't lay the knife flat on the stone, but I did sharpen between 10-15° does anyone have any idea how I can fix this? I've had the same issue on other knives before and it is frustrating. And yes, this knife does have a Damascus pattern that i would like to retain


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## ian (Jan 1, 2021)

Tnaquin35 said:


> Hey guys,
> So I was sharpening a Shun Classic Chef's knife for my Sous Chef last night and after running it on my 1k, I noticed some odd spots on the side of the blade that looked like it was hit with a buffing wheel. I obviously didn't lay the knife flat on the stone, but I did sharpen between 10-15° does anyone have any idea how I can fix this? I've had the same issue on other knives before and it is frustrating. And yes, this knife does have a Damascus pattern that i would like to retain



There are basically only two possible issues here:

1) You aren’t holding the angle well.

2) Your stone isn’t flat.

If it’s 1), practice. If it’s 2), get an Atoma 140 or something and flatten your stone.


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## Tnaquin35 (Jan 1, 2021)

Im pretty sure I was holding the angle well, but I dont use any guides or anything so it is possible, but I've been doing this for 4 years and just recently started having this problem. And its been a little while since I flattened that stone. Any idea on how I can clean up the marks on the knife without power tools?


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## drsmp (Jan 1, 2021)

To improve the look first I would try micro mesh pads - use a high grit first and sand heel to tip.


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## ian (Jan 1, 2021)

I don’t have a ton of experience with micromesh, but sandpaper will clean it up too, say starting at 1k, or 800? Can just do heel to tip strokes as @drsmp says. You’re going to have to refinish the whole blade to make it look nice, rather than touching up those individual spots. You’ll lose some of the contrast in the damascus pattern doing this. The only ways I’ve found to really restore the contrast (short of owning a bead blaster or whatever they use to create it at the factory) is to etch it or to use fingerstones. Etching will be more dramatic, but I haven’t been able to get an etch on a Shun that really looked good. I’ve only tried 3 times though. Fingerstones give a mild contrast, but it does look ok imo.


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## M1k3 (Jan 1, 2021)

ian said:


> I don’t have a ton of experience with micromesh, but sandpaper will clean it up too, say starting at 1k, or 800? Can just do heel to tip strokes as @drsmp says. You’re going to have to refinish the whole blade to make it look nice, rather than touching up those individual spots. You’ll lose some of the contrast in the damascus pattern doing this. The only ways I’ve found to really restore the contrast (short of owning a bead blaster or whatever they use to create it at the factory) is to etch it or to use fingerstones. Etching will be more dramatic, but I haven’t been able to get an etch on a Shun that really looked good. I’ve only tried 3 times though. Fingerstones give a mild contrast, but it does look ok imo.


Muriatic acid? I heard to use that on stainless, followed by ferric chloride etch.


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## ExistentialHero (Jan 1, 2021)

M1k3 said:


> Muriatic acid? I heard to use that on stainless, followed by ferric chloride etch.



I've also seen some folks use a strong batch of instant coffee--not sure if that's in addition to or instead of the ferric chloride.


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## ian (Jan 1, 2021)

M1k3 said:


> Muriatic acid? I heard to use that on stainless, followed by ferric chloride etch.



Yea, haven’t tried. Maybe that’s the answer. Ferric chloride is all I have.


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## drsmp (Jan 1, 2021)

I used to buy, repair and resell damaged Shun and Miyabi on eBay. Please try the micro mesh first.


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## Migraine (Jan 1, 2021)

I second micro mesh.


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## ian (Jan 1, 2021)

drsmp said:


> I used to buy, repair and resell damaged Shun and Miyabi on eBay. Please try the micro mesh first.



Noone doubts your credentials, but it might be more useful to say why you prefer micromesh. I’d be interested at least, since my very limited experience with micromesh hasn’t indicated to me that it’s much different than soft backed sandpaper. But I would like to be corrected and learn...


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## stevenStefano (Jan 1, 2021)

I've seen scratches like that when I used a ceramic hone on my knives and was careless, but never from the stones


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## SeattleBen (Jan 1, 2021)

stevenStefano said:


> I've seen scratches like that when I used a ceramic hone on my knives and was careless, but never from the stones




If I hadn't read the thread and seen that you did that with a stone that'd be my first guess as to how that happened. 

If you sand it, prepare to go lower than you think since the grits on sandpaper and stones don't necessarily correlate to the same numbers.


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## drsmp (Jan 1, 2021)

Regarding micro mesh - it often worked for scratched Shun/Miyabi. Worst case it may look good enough and avoid the need for a full refinish. The shun Damy is hard to etch and get a factory look. So if you refinish one side with sandpaper and etching you’ll need to do both so they match. Start with something that makes a minimal impact and go from there.


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## ian (Jan 1, 2021)

drsmp said:


> Regarding micro mesh - it often worked for scratched Shun/Miyabi. Worst case it may look good enough and avoid the need for a full refinish. The shun Damy is hard to etch and get a factory look. So if you refinish one side with sandpaper and etching you’ll need to do both so they match. Start with something that makes a minimal impact and go from there.



What’s the difference between micro mesh and a possibly higher grit sandpaper, though? Is there a quality to it that preserves the finish better for some reason? I don’t really understand what the difference is.


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## drsmp (Jan 1, 2021)

One stray large grit on sandpaper and things get ugly in a hurry. Don’t have that problem with micro mesh. MM doesn’t leave any appreciable scratch patterns at high grit. I trued a lot of techniques in my eBay buy/sell days and usually MM worked for scuffed up Shun finishes
Here’s info from a wooed working webpage
With regular sandpaper, a flat back keeps the abrasive on the same level plane for a more consistent cut. Micro-Mesh solves the scratch problem by going in a completely different direction. The cushioned backing works like a pressure-safety valve, allowing the grit to sink in so that the cutting tips contact the sanding surface at the same level. This grit-backer combination results in a more refined scratch pattern. (Although it’s great for polishing, the cushioned backing makes the paper less aggressive. For removing deep scratches, you’ll want to switch over to regular sandpaper.)


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## ian (Jan 1, 2021)

drsmp said:


> One stray large grit on sandpaper and things get ugly in a hurry. Don’t have that problem with micro mesh. MM doesn’t leave any appreciable scratch patterns at high grit. I trued a lot of techniques in my eBay buy/sell days and usually MM worked for scuffed up Shun finishes
> Here’s info from a wooed working webpage
> With regular sandpaper, a flat back keeps the abrasive on the same level plane for a more consistent cut. Micro-Mesh solves the scratch problem by going in a completely different direction. The cushioned backing works like a pressure-safety valve, allowing the grit to sink in so that the cutting tips contact the sanding surface at the same level. This grit-backer combination results in a more refined scratch pattern. (Although it’s great for polishing, the cushioned backing makes the paper less aggressive. For removing deep scratches, you’ll want to switch over to regular sandpaper.)



Cool. I usually have a soft backing on my sandpaper for this kind of refinishing work, but maybe the MM is taking it a little further by having the give be a part of the product itself. Maybe that gives it a little more flexibility than with sandpaper, where even with a soft backing there’s some structure to the paper. And if you say the grit is also more uniform, that’s a plus. Maybe I’ll have to bring out the MM and test it out again.


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## Midsummer (Jan 1, 2021)

@drsmp DO you use any lubricant to keep the mesh from clogging like oil or water?


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## drsmp (Jan 1, 2021)

Just my experience as best quick repair for Shun. Deep scratches aren’t coming out short of full refinish 
Try dry pad and light pressure first. A little windex or water if full progression of MM


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## inferno (Jan 1, 2021)

when in doubt - angle grinder!


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## M1k3 (Jan 1, 2021)

inferno said:


> when in doubt - angle grinder!


I hear it's a good way to remove 30mm


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## Tnaquin35 (Jan 1, 2021)

drsmp said:


> One stray large grit on sandpaper and things get ugly in a hurry. Don’t have that problem with micro mesh. MM doesn’t leave any appreciable scratch patterns at high grit. I trued a lot of techniques in my eBay buy/sell days and usually MM worked for scuffed up Shun finishes
> Here’s info from a wooed working webpage
> With regular sandpaper, a flat back keeps the abrasive on the same level plane for a more consistent cut. Micro-Mesh solves the scratch problem by going in a completely different direction. The cushioned backing works like a pressure-safety valve, allowing the grit to sink in so that the cutting tips contact the sanding surface at the same level. This grit-backer combination results in a more refined scratch pattern. (Although it’s great for polishing, the cushioned backing makes the paper less aggressive. For removing deep scratches, you’ll want to switch over to regular sandpaper.)


I'll definitely have to get some! Luckily Chef took the knives and paid me for it so I'm not complaining lol. Even got some extra business doing her parent's knives lol. Now I'm stuck with a bent tip tojiro paring knife  not too hard to fix though. But back to the Shun, I have some rubber rust erasers from sandflex, I got the course, medium, and fine combo. Do you think one of those would work if I needed it in a pinch?


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## Jovidah (Jan 2, 2021)

If you want to scratch more Shuns then yeah that'll work.


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## Nhwk (Jan 2, 2021)

I've made knives for a number of years now.. I'll tell you, that is a knife maker's worst fear when finish sharpening a Damascus blade, but it happens to the best. Most custom knife makers will tape the sides of the blade to help prevent it. just leave the very edge of the cutting edge exposed

The amount of work will depend on the grit of the stone you scratched it on. If really fine I'd hit it with abrasive paper one or two steps up from the stone you scratched it on as mentioned start at the heal and in one continuous stroke down to the tip. Come straight off the tip don't push down. If you do, it can thin and roll that tip over. 

This will take off the etch or most of it, from the factory. The pattern will fade, but it's easily brought back. As mentioned a mixture of water and ferric chloride will bring back the etch. Clean the blade well with soap and water then alcohol or window cleaner before you etch. Put the knife in for a minute or two and check on it. From the factory, the blade won't have a really deep etch just good contrast. So I'd dip it twice a couple of minutes apart. Between dips, take 00 steel wool or even just a paper towel and lightly rub the oxide off the blade. Keep a bottle of Windex around for the last dip into the acid. Once you take it out you need to spray it down with Windex to neutralize the acid.

You will have to play around with this process to get it where you think it looks best. Some will cover the very cutting edge with fingernail polish to protect it from the acid or you re-sharpen after etch.

This is the point where the maker would take the blade to the buffer. Be warned the buffer looks cute and cuddly with his fuzzy wheel, but the buffer is the most feared piece of equipment in the shop. The buffer can cause a really bad injury very fast. On stainless, I lightly buff the steel to bring the shine back to the stainless. If you don't have access to a buffer I'd just use some over-the-counter stuff and hand rub it on, again ( lightly.) 

Coffee etches: I have found instant coffee works best, but this method introduces a lot of colors that can or cannot be desired. I prefer to use this method on all my kitchen knives made from carbon. Folks love the red, blue, and gray hues brought on by the acids in the coffee. I don't sand between dips on coffee etches. just soap and water with a paper towel. Light buffing by hand will remove the colors and leave contrast as well. I'm not sure how well this method will work on stainless steel. I use it on carbon steel because it is a food-safe etch. 

The last recommendation is .. take it to a knife maker and see what he or she will charge you to refinish the knife, just tape the cheeks from here on out. Sorry for the book but I wanted to give you some detail and up your odds of success.


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## Staystrapped (Jan 2, 2021)

inferno said:


> when in doubt - angle grinder!


With a 36 grit wheel my favorite!


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