Sharpening Neglected Knives

[RustyIron]

In this scenario, how long does it usually take you to get the edge apexed?

That scenario typically doesn't apply to me. I don't work on junk knives. Garbage knives take a long time to work on, and when they're done, they're not all that great. It's a waste of time.

One exception was a Chinese cleaver. The owner found it someplace and thought it was really nice. I thought I was cool, so I agreed. I probably spent a few hours on it. In reality, it was an eight dollar knife available from multiple online sources.

Another exception was an heirloom that had personal significance for its owner. It was in a fire and was completely ruined. A replacement could be found for $250. However, the owner is a good friend. I probably spent 20 hours on it, and it certainly wasn't "like new" when I was finished.

But if it's a "good" knife, I can usually turn it into something nice in an hour or less. If it looks like it will take longer, then it's probably seen more abuse than I care to repair.

[Ramonade]

There even are cheap knives that cant really get a burr. My uncle asked mebto sharpen one of his kitchen knives.

I'm pretty positive that it uses pot steel and cant be hardened because I could only give it the shape of an edge with a relatively fat apex. The steel did crumble on itself as soon as the apex was getting thin.

Still cuts, but a terrible sharpening experience with how mushy it was.

[Evil D]

The number of hunters out there with crap knives is really shocking. Almost as if knives are an afterthought and no more than that. I've field dressed and skinned more that a few carcasses for friends. One dentist friend of mine actually went deer hunting without so much as a pocket knife. He dropped a nice buck and spent the entire morning into afternoon searching for me all over Ft Hunter Liggett. Never seen a guy so happy when he finally did find me.

I can't tell you how many videos I've seen of hunters rescuing trapped animals and trying to cut them loose with what seems like dull butter knives. That same guy has hundreds if not thousands of dollars in his hunting gear but carries a dull knife.

[ZrowsN1s]

Just an fyi to people thinking of using super coarse stones, they can really jack up your apex and leave little gouges in it (best seen with a loupe). Use the 50 grit to reprofile and get close to the apex. Then switch to 200 grit to get to the apex, then refine from there. Otherwise you may spend a lot of time sharpening out the gouges in the apex. (May not matter if you're going for a 'coarse finish'.

[vandelay]

Maybe 5 minutes for a chipped blade on a DMT x-coarse stone. Those really chew through steel.

How? I've got a lot of very coarse hones--an Atoma 140, a Shapton 120 and a Baronyx Knife Co "Manticore" that's a 60 grit SiC stone--but none of them will repair or reprofile a very blunt blade in less than an hour or two. I've heard similar time estimates before but can never understand how it's possible unless you're all using super fast strokes and tons of pressure or something, but even when I have tried that it doesn't seem to speed things up at all.

It depends on more than the grit. I have a 120 grit flattening stone from my old sharpening set. It sounds aggressive but the grit isn't very exposed so it barely takes steel off. The DMT x-coarse stone is incredibly aggressive (it's visibly coarse), so it's able to just grind away steel really quickly. The downside is that it's so aggressive that you need to grind on a higher grit for the edge to actually cut anything (it also microchips higher carbide steels).

I've sharpened a number of kitchen knives for family. They're usually 1.4116 or 440A, totally blunt and have sizeable chips. I just do rapid short strokes and it grinds the steel away fast enough to get it back to a rough apex in a few minutes. I don't time it so maybe 5 minutes is an exaggeration.

I use a similar technique to what's shown in this video (except I'm much worse at it):
https://youtu.be/QIo9p4W_QJ8

I'm also not really sure why people are suggesting soft knives are any harder to grind? I have just heard it's harder to deburr them.

Yeah, in terms of just removing metal, I remember it being easier on really low carbide steels back when I used an aluminum oxide stone. With diamonds, they all feel about the same. When trying to get a good apex, you can run into burr formation and microchipping, but that's only a real problem once you've got a rough apex.

Burr formation can be really annoying on some low carbide steels though. I remember cleaning up a chip in a 1095 knife and getting a visible burr that was at least 0.5mm long.

[kennbr34]

Maybe 5 minutes for a chipped blade on a DMT x-coarse stone. Those really chew through steel.

How? I've got a lot of very coarse hones--an Atoma 140, a Shapton 120 and a Baronyx Knife Co "Manticore" that's a 60 grit SiC stone--but none of them will repair or reprofile a very blunt blade in less than an hour or two. I've heard similar time estimates before but can never understand how it's possible unless you're all using super fast strokes and tons of pressure or something, but even when I have tried that it doesn't seem to speed things up at all.

It depends on more than the grit. I have a 120 grit flattening stone from my old sharpening set. It sounds aggressive but the grit isn't very exposed so it barely takes steel off. The DMT x-coarse stone is incredibly aggressive (it's visibly coarse), so it's able to just grind away steel really quickly. The downside is that it's so aggressive that you need to grind on a higher grit for the edge to actually cut anything (it also microchips higher carbide steels).

Interesting, I always thought it was basically on par with the Atoma 140. Have you used one of those to be able to offer a comparison?

[vandelay]

Maybe 5 minutes for a chipped blade on a DMT x-coarse stone. Those really chew through steel.

How? I've got a lot of very coarse hones--an Atoma 140, a Shapton 120 and a Baronyx Knife Co "Manticore" that's a 60 grit SiC stone--but none of them will repair or reprofile a very blunt blade in less than an hour or two. I've heard similar time estimates before but can never understand how it's possible unless you're all using super fast strokes and tons of pressure or something, but even when I have tried that it doesn't seem to speed things up at all.

It depends on more than the grit. I have a 120 grit flattening stone from my old sharpening set. It sounds aggressive but the grit isn't very exposed so it barely takes steel off. The DMT x-coarse stone is incredibly aggressive (it's visibly coarse), so it's able to just grind away steel really quickly. The downside is that it's so aggressive that you need to grind on a higher grit for the edge to actually cut anything (it also microchips higher carbide steels).

Interesting, I always thought it was basically on par with the Atoma 140. Have you used one of those to be able to offer a comparison?

I've never tried one of those. It looks pretty aggressive from pictures though. Maybe this is just down to technique or how severely abused the knives are then.

[kennbr34]

How? I've got a lot of very coarse hones--an Atoma 140, a Shapton 120 and a Baronyx Knife Co "Manticore" that's a 60 grit SiC stone--but none of them will repair or reprofile a very blunt blade in less than an hour or two. I've heard similar time estimates before but can never understand how it's possible unless you're all using super fast strokes and tons of pressure or something, but even when I have tried that it doesn't seem to speed things up at all.

It depends on more than the grit. I have a 120 grit flattening stone from my old sharpening set. It sounds aggressive but the grit isn't very exposed so it barely takes steel off. The DMT x-coarse stone is incredibly aggressive (it's visibly coarse), so it's able to just grind away steel really quickly. The downside is that it's so aggressive that you need to grind on a higher grit for the edge to actually cut anything (it also microchips higher carbide steels).

Interesting, I always thought it was basically on par with the Atoma 140. Have you used one of those to be able to offer a comparison?

I've never tried one of those. It looks pretty aggressive from pictures though. Maybe this is just down to technique or how severely abused the knives are then.

Yeah or it's possible I just don't use it enough to have a good impression of it. I repaired a knife with a huge scandi grind on it that took forever, but that might be a bad one to compare with other knives since it was such a large surface area. I had to grind out a chip on some 10V with a standard bevel that went super fast though. Otherwise I don't use the Atoma much because I also use it to flatten my straight razor hones and I have been told using it to sharpen and flatten isn't a good idea.