Filet knife sharpening; level of polish

[bgentry]

I've been sharpening a decent number of filet knives in the last month or so. I did a little searching here and found that most people think leaving a filet knife edge sort of rough is the way to go. I've seen advice from 220 grit to 450 (from what I remember anyway).

I've been using the WSKO to do all of these, and have stopped variously at 100 micron (~120 grit), 22 micron (~450 grit), and as high as 4 micron (~1500 grit). Unfortunately, I've gotten zero feedback from my customers, so I have no idea how the perform when cutting fish.

The last one I did, I left at 100 micron, but did 3 or 4 very light, very fast passes, at the slowest speed, on the 5 micron belt, hoping to eliminate the burr, *and* to micro polish the edge. The result was a blade that shaved hair, but not very cleanly, and cut phonebook paper, but was VERY loud and tore it in spots. It felt very sharp and "bitey" to the fingers and sliced into an over ripe tomato cleanly. It would not push into the tomato; only slice. That particular blade had dozens of chips in the edge, and I may have left a shallow chip or two behind which hung in the paper; not 100% sure on that.

I guess I'm asking two things:

1. What finish do you like on filet knives for good performance and long service life between sharpenings?
2. Any thoughts on stopping at a low grit level (very coarse stone or belt) and doing finishing strokes on a high grit level (fine stone or belt)?

Thanks guys.

Brian.

 

[Jason B.]

Depends on the fish and the skill of the user. Most people I know including myself like a very coarse edge on a filet knife. The coarse side of a aluminum oxide stone or a coarse DMT are two that I like.

Changing knife styles and moving to a Japanese Deba my preference changes to a medium polish with a 2k-3k waterstone.

In any case it's best to know what the user is doing. If they are making final cuts of the filet then a high level of refinement is required, if basic butchering where bone contact is common a more obtuse and coarser edge works best.

 

[Ankerson]

Usually something in the 300-400 grit range is fine for most use.

 

[Obsessed with Edges]

A lot of fillet knives will be in relatively low-carbon stainless steels (some have used simple stainless like 420J2); these often won't be very hard and won't hold a high-polished edge very long at all. The main emphasis for them is corrosion resistance (chromium content is usually very high), as well as flexibility and toughness, instead of edge-retention (higher carbon is needed for this, but that also acts to accelerate corrosion in knife steels). Therefore, these blades are the ones that usually do better with a coarser edge finish, as mentioned above.


David

 

[bgentry]

Thanks for the replies gentlemen. Seems to reinforce what I read previously.

Does anyone have an opinion on how I finished my last blade, using a 100 micron belt for primary sharpening and then deburring on a 5 micron belt? I would seem to be a good combo edge, but I haven't fileted a fish in 20+ years and I was terrible at it back then!

This "refined toothy edge" is something I might experiment with on my EDC blades as well.

Brian.

 

[jackknife]

Fish bellies are slippery. Fish guts are slippery. A polished blade will slide too much gutting and cleaning a fish. I use just a very toothy edge. Either the course side of a stone, or even a mill smooth file edge. My fish knives and machete's are all used with a very toothy edge and for mod things it works out better.

 

[Obsessed with Edges]

Fish nellie are slippery. Fish guts are slippery. A polished blade will slide too much gutting and cleaning a fish. I use just a very toothy edge. Either the course side of a stone, or even a mill smooth file edge. My fish knives and machete's are all used with a very toothy edge and for mod things it works out better.

I used to be fascinated watching my Dad sharpen a Japanese-made 'Sabre' 624 yellow fish knife (stainless) with a small triangular file, when I was a kid. He used that knife to clean a whole bunch of rainbow & brown trout caught during our family camping & fishing trips in NM and CO. I'm not sure what originally motivated him to use the file for that job, but there seems to have been some wisdom in the results; that knife unzipped those fish like a toothy laser.


David

 

[jackknife]

I used to be fascinated watching my Dad sharpen a Japanese-made 'Sabre' 624 yellow fish knife (stainless) with a small triangular file, when I was a kid. He used that knife to clean a whole bunch of rainbow & brown trout caught during our family camping & fishing trips in NM and CO. I'm not sure what originally motivated him to use the file for that job, but there seems to have been some wisdom in the results; that knife unzipped those fish like a toothy laser.


David

Your dad knew what he was doing. He was drawing on his own experience of what works and what doesn't. He didn't spend any time on a knife forum, probably didn't read any knife magazines, or obsess over whittling hair with an edge that didn't really work out well in a real life situation.

Too many people do obsess over having a mirror polished edge that will tree top hair, but how often do you need a razor in real life? But, if you have a deer to field dress, some fish to clean, or some dirty wet rope to cut through, a toothy course edge will do better, and after the deed will still be ready to cut. There's a cut off point on knife sharpening, that after a certain point, is just bragging rights with no real world practical use. I once watched my friend Chet, who is a flint knapper, out cut another friend, using one of his own obsidian blades with a 2 inch blade. That obsidian knife with a scalloped pressure flacked edge, out cut a Randall bird and trout knife with a smooth razor edge. Then he went on to demonstrate with a made in China gas station knife with a file sharpened edge, do it again against Danny's Randall with the polished blade.

I've been around this rock long enough to see that the most hyped, over priced, objects fail against a common lower echelon object.

 

[Ankerson]

I used to be fascinated watching my Dad sharpen a Japanese-made 'Sabre' 624 yellow fish knife (stainless) with a small triangular file, when I was a kid. He used that knife to clean a whole bunch of rainbow & brown trout caught during our family camping & fishing trips in NM and CO. I'm not sure what originally motivated him to use the file for that job, but there seems to have been some wisdom in the results; that knife unzipped those fish like a toothy laser.


David

Back in the day a lot of us used files to sharpen knives that we needed to use continuously, you wouldn't believe the edge you can get and it cut like crazy....

The knives were cheap so it's really didn't matter how fast we wore them out....

 

[Obsessed with Edges]

Your dad knew what he was doing. He was drawing on his own experience of what works and what doesn't. He didn't spend any time on a knife forum, probably didn't read any knife magazines, or obsess over whittling hair with an edge that didn't really work out well in a real life situation.

Too many people do obsess over having a mirror polished edge that will tree top hair, but how often do you need a razor in real life? But, if you have a deer to field dress, some fish to clean, or some dirty wet rope to cut through, a toothy course edge will do better, and after the deed will still be ready to cut. There's a cut off point on knife sharpening, that after a certain point, is just bragging rights with no real world practical use. I once watched my friend Chet, who is a flint knapper, out cut another friend, using one of his own obsidian blades with a 2 inch blade. That obsidian knife with a scalloped pressure flacked edge, out cut a Randall bird and trout knife with a smooth razor edge. Then he went on to demonstrate with a made in China gas station knife with a file sharpened edge, do it again against Danny's Randall with the polished blade.

I've been around this rock long enough to see that the most hyped, over priced, objects fail against a common lower echelon object.

Back in the day a lot of us used files to sharpen knives that we needed to use continuously, you wouldn't believe the edge you can get and it cut like crazy....

The knives were cheap so it's really didn't matter how fast we wore them out....

Dad was never a knife/sharpening 'nut' like some of us here, which is why I'm not sure about his original motivation for using the file on that blade, or even if he ever tried using anything else. I'm thinking it's likely it was a choice of convenience or availability, and as Carl mentioned, he found that it worked for him. Knowing what I know now, it's perfectly logical in seeing why it works well (softish stainless usually does respond better to coarser edges), but it's interesting to me in seeing how he seemingly found the 'right' solution in the end. Watching him sharpen that knife is (I think, in retrospect) what really piqued my interest in all this in the first place.


David

 

[jackknife]

Watching people sharpen a knife in different places all over the world is an education. For a while, I was a knife snob. I had the kit that traveled with me, that had the soft Arkansas stone, the hard Arkansas stone, the loaded strop, the special Buck honing oil. I would never have dreamed of using a file on a knife, being a crude abomination of a deed to a nice knife.

But in many of the parts of the world where a sharp knife is needed, they are not so near as persnickety as we are. Spending 10 years in the army, I was stationed in Italy, where I watched knives being honed on the stone steps of the house by the housewives getting ready to make supper. In Libya where we got sent to the old Wheelus Air Force base to lengthen and re-enforce the runways for B-52's, I watched merchants in the stalls of the market use the cobble stones of where ever their stalls were set up, to sharpen the knives. They then sliced up the lamb for kabobs very easy. The toothy edge went right through the raw meat with no problem.

Several years ago, our son was sent to Costa Rica for 6 months on business for his company. We went to visit, and John surprised us with a guided echo trip in the rain forest. Knowing how we were avid nature watchers with our binoculars, we had a nice camping/hiking trip in the jungle lasting for a few days. We'd hike trails, and each night the camp was someplace along where we were traveling. The guides set up camp each night, and made dinner, and they all carried a small 12 inch machete in their belt. It was used for all manner of jobs, including clearing the campsite, cooking dinner, and chopping kindling of the campfire. Each guide carried a small 6 or 8 inch mill smooth file to sharpen his machete. I noticed that they had ground off the teeth of the file on one side, leaving that side of the file smooth, and used it like a steel on the blade after a file sharpening. The one guide who spoke very good English, showed me how sharp they got that small machete. It was thumb print grabbing sharp. Wicked. On the last night in jungle, they put on a pig roast for us, and the cooked pig was sliced up and served with the small machetes. Sliced the pork probably better than a chefs favorite knife.

I eventually got over my knife snobbery, and now have gone peasant in my approach to knives and sharpening. I am happy not to obsess over it anymore, because it leaves me more time for fishing, traveling, and spending time in my retirement with my better half. I refuse to spend more than 5 or 10 minutes sharpening a knife. It's more fun using the knife in doing what I enjoy.

 

[B34NS]

Well said jacknife.

I prefer the same in terms a toothy edge. I've had externs come in and mirror out our fillet knives trying to be helpful only to watch us dull down they're time spent. One of my personal heroes Justo Thomas, fish butcher at Le Bernadin in NYC uses the same method.

[video=youtube;MyOB10Z-dSQ]https://www.youtube.com/watch?v=MyOB10Z-dSQ[/video]

 

[HwangJino]

I cut fish for a living, a highly polished blade works best.

If a polished blade slips on belly or whatever, it's not sharp enough.

But then again, I've never actually used a filled knife, just sujihiki (long thinner version of chef knife/gyuto).

 

[Ankerson]

I cut fish for a living, a highly polished blade works best.

If a polished blade slips on belly or whatever, it's not sharp enough.

But then again, I've never actually used a filled knife, just sujihiki (long thinner version of chef knife/gyuto).

Totally different knives.

Filet knives, the good ones are extremely thin and have a medium to large flex towards the tip, think boning knife but much better......

And they are a lot shorter from edge to spine than the typical sujihiki..... And really thin down toward the tip, and the spine is VERY thin and usually distal taped from handle to tip.....

 

[HeavyHanded]

Watching people sharpen a knife in different places all over the world is an education. For a while, I was a knife snob. I had the kit that traveled with me, that had the soft Arkansas stone, the hard Arkansas stone, the loaded strop, the special Buck honing oil. I would never have dreamed of using a file on a knife, being a crude abomination of a deed to a nice knife.

But in many of the parts of the world where a sharp knife is needed, they are not so near as persnickety as we are. Spending 10 years in the army, I was stationed in Italy, where I watched knives being honed on the stone steps of the house by the housewives getting ready to make supper. In Libya where we got sent to the old Wheelus Air Force base to lengthen and re-enforce the runways for B-52's, I watched merchants in the stalls of the market use the cobble stones of where ever their stalls were set up, to sharpen the knives. They then sliced up the lamb for kabobs very easy. The toothy edge went right through the raw meat with no problem.

Several years ago, our son was sent to Costa Rica for 6 months on business for his company. We went to visit, and John surprised us with a guided echo trip in the rain forest. Knowing how we were avid nature watchers with our binoculars, we had a nice camping/hiking trip in the jungle lasting for a few days. We'd hike trails, and each night the camp was someplace along where we were traveling. The guides set up camp each night, and made dinner, and they all carried a small 12 inch machete in their belt. It was used for all manner of jobs, including clearing the campsite, cooking dinner, and chopping kindling of the campfire. Each guide carried a small 6 or 8 inch mill smooth file to sharpen his machete. I noticed that they had ground off the teeth of the file on one side, leaving that side of the file smooth, and used it like a steel on the blade after a file sharpening. The one guide who spoke very good English, showed me how sharp they got that small machete. It was thumb print grabbing sharp. Wicked. On the last night in jungle, they put on a pig roast for us, and the cooked pig was sliced up and served with the small machetes. Sliced the pork probably better than a chefs favorite knife.

I eventually got over my knife snobbery, and now have gone peasant in my approach to knives and sharpening. I am happy not to obsess over it anymore, because it leaves me more time for fishing, traveling, and spending time in my retirement with my better half. I refuse to spend more than 5 or 10 minutes sharpening a knife. It's more fun using the knife in doing what I enjoy.

On lower RC stainless and carbon steel all manner of tools can make a tremendous edge. I used to use a straight bladed corn knife made in Austria for cutting the wild grape vines on my property and is impressive what one can do with just a smaller mill file, either with a straight cut or used like a draw file. I never thought of grinding down one side to use as a honing steel, but did work some black compound right into the dowel that is the handle of the file. Reverse it and use the handle like a steel/strop, good enough to shave arm hair and very fast to touch up and repair. I switched to other methods that make a finer edge just as fast and a bit more reliably for me, but have never forgotten and wouldn't feel bad about going that route again. Is only on higher RC and higher alloy content fare that improvised methods start to falter.

To the OP, for most filet knives a fairly acute angle and a toothy edge are the way to go.

 

[HwangJino]

I guess my opinion is bias since I've held my sujihiki for over 5 years 10 hours a day... I did polish the kitchen filet knife and the crew loves the polish.

 

[jackknife]

I guess my opinion is bias since I've held my sujihiki for over 5 years 10 hours a day... I did polish the kitchen filet knife and the crew loves the polish.

Well you know what they say: YMMV!

 

[the possum]

A buddy at work here got a nice Phil Wilson fillet knife. The knife came with Phil's toothy edge like many are describing here. My friend was not happy with that edge, since he's using it to fillet small pan fish. They aren't big/heavy enough to stay still if ya try to use a sweeping/slicing motion to take advantage of that toothy edge, and just flop and scoot all over the cutting board. He greatly preferred using his old fillet knife that I'd sharpened with a finer (but not highly polished) edge. I'm not much of a fisherman, so I relied on his feedback and we experimented with the polish level left by several different stones in my collection, and then he got one himself. He finally settled on the mix of push cutting ability and toothiness left by a 3000 grit Japanese ceramic water stone.