The Shocking Truth About Ceramic Knives

four years ago I bought one of these a ceramic knife in a world where ceramic knives are known to be throwaway consumables one man stands in the way I tried it out and realized it was insane in one area Edge retention that's on my cardboard so I think in terms of cutting up cardboard I don't think that there's any knife out there that could be a ceramic knife yes it does beat CPM M4 by a long shot it's not even close I saved up a lot of cardboard for this and uh probably over 1,000 ft of cardboard no lie I mean I think it was around 45 uh 45 Cuts 18 in of cardboard we lost that absolute shaving Edge but it stayed at that pretty much that same sharpness throughout the rest of this cutting test and hasn't really dled much since then so um let's see if we can sharpen this back to shaving chart but the problem is is that when it finally did do I completely failed at resharpening it Place foone book paper and most definitely will not shave so I don't know how to make it sharper at least not without resorting to some Extreme [Music] Measures now there is one area in my life where I have never failed and that is knife sharpening I've never failed to sharpen a knife except for this one I felt defeated I don't know how to make it sharper so here we are 4 years later let's take another look at ceramic knives give it another try and try to dispel some of the myths surrounding ceramic knives some of which I may be responsible for I know what's going on here how do I sharpen this thing I don't know because I was wrong I was wrong about these sort of right out of the box this is what the factory New Edge looks like up close under the microscope so are we going to have the same chipping issues we had before after some use now I know from past testing and current testing that a ceramic knife will hold a better working Edge than any steel knife cutting cardboard period it's not even close if your job is to cut cardboard all day long then choose a ceramic knife how much cardboard does the average person really cut up now I was going to give accurate cardboard cutting numbers here in feet but I ran out of cardboard before this knife would stop cutting pretty thin graph paper now the Shaving Edge was gone after about 47 ft fet of cardboard and here's what that non shaving Edge after 47 ft of cardboard looks like up close oh boy an absolute chippy nightmare of a fine apex but the working Edge held on forever for a lot of stuff these very fine microchips don't really matter so the working Edge isn't really that affected only for the very fine tab asks like shaving can you really tell a difference so at this point the only thing that I could do was to see whether or not I could put the Shaving Edge back on this knife now I sat down for hours and hours this time trying to sharpen this knife this time using resin bonded Stones rather than the plated Diamond Stones I was using uh several years ago that was causing all of the chipping issues so the thing is if I take my finger and run it down the edge it feels like there's a like microchipping feels I can feel it feels like chips and after hours of trying I was running into problems the problem is is that I kept getting chipping again as soon as I was apexing it doesn't really shave I mean sure you could get it to shave if you like force it down and like tear hairs out and whatever but I think that that is due after looking at the up close image that's due to the Sal tooth nature of the Apex basically as soon as the edge came to an exact point it would break off and I'd have to start all over now I did this over and over and over again somehow thinking that the basic principles of sharpening somehow don't apply to ceramic knives and trying numerous different resin bonded Diamond Stones thinking that the problem was the stone and not me and suddenly it dawned on me we're back to shaving I think we may have figured it out if I was having the same problem with a steel knife rather than a ceramic knife what would I do I would increase the sharpening angle relative to the stone making the Apex more obuse thus solving the Apex stability problems and so that's what I did so I just cut some more cardboard I've taken away I've just taken away that hair uh shaving Edge I mean it is just on the verge of not shaving now I want to see how quickly I can put it back the light passes on the V 1200 all right we're shaving right off the stone I I think I figured it out all this time my problem it's not what I thought it was and like magic turns out ceramic doesn't like very acute angles it doesn't like pointy angles on KN it simply lacks the Apex toughness to hold those more extreme edge geometry angles who would have thought it's almost like someone has been saying this exact thing for years here on YouTube I don't know who that person could be so once I finally realized this and started following my own advice how long does this take to [Music] sharpen all right we're shaving right off the stone so here's what this Edge looks like this is off of a v 1200 which is actually about a 3,000 grit Stone and dropped on a 1 Micron and 1/10th Micron Diamond STP my findings are that ceramic dos via chipping it doesn't really wear away like traditional Steel and you can see this right here with the CPM M4 blade both the ceramic knife here and the CPM M4 blade here have the same amount of cuts the ceramic chips the M4 sort of abrades away now keep in mind this 59 seconds was to Simply bring it from a working Edge back to shaving sharp bringing it from a truly messed up Apex like this one here requires you to go through an entire grit progression just like a steel knife only rather than creating a burr ceramic makes chips the finer you go the smaller the chips and the sharper the knife now I only use $280 worth of sharpening stones to bring this Edge back from a truly doll state in other words ceramic dolls via chipping and resharpen Via chipping now in terms of where do the chips go if you're using this for food prep and is ingesting ceramic chips versus Metal dust any better or worse for you I have absolutely no idea but speaking speaking of food prep another reason you'll hear people say they use ceramic knives versus steel knives is to keep the food from oxidizing due to the ceramic knife's lack of transfering ions from the blade to the food unlike its steel counterparts now this sounds like absolute hogwash to me so I decided to test it out first I cut a banana with a freshly sharpened ceramic knife and a typical $1 freshly sharpened stainless steel knife to see which one brown over first all right the results of our banana test are that they look almost identical I really can't tell the difference here this was the ceramic I believe and this was the uh stainless steel and they pretty much look identical now you may be saying to yourself well you didn't let them sit out long enough to tell a difference well these set out for 2 hours enough said now how about an apple surely we can tell a difference with an apple stainless steel ceramic so now for the results of our Apple you tell me down below which one you think is the ceramic and which one you think is the steel do it do it now pause the video and go tell me below no cheating now this one right here is the ceramic this one right here is the steel now to give you an idea these have been sitting out for 2 hours and that is the difference in the Apple test the sharp versus du test so now what if we cut an apple with a sharp knife in a dll knife I wanted to try something what if we cut one apple with a steel Sharp knife and one apple with the same steel knife but we doll it so it's along the same condition as the vast majority of people's steel kitchen knives are doll including mine we have significantly higher oxidizing on the doll knife cut Apple if you look at these up close you can see just how much cleaner the sharp knife cuts the Apple versus the doll knife and you can clearly see at least I can clearly see here in real life I hope you can see this on camera we have signicantly more oxidizing on the Apple that was cut with the dll knight in my opinion based on my test the reason people think Ceramics produce less oxidation is because most people's Ceramics are going to be sharper than their doll kitchen knife people buy Ceramics because they are told that they stay sharp longer and they do so out of the box testing compared to a dollar steel knife will produce less oxidation however when you compare sharp ceramic versus actually sharp steel the results are even based on what I'm seeing so less oxidation has more to do with the doll knife ripping apart food fibers producing more surface area than it does transferring ions or something like that now yes there may be other tests out there cutting specific things where there's a bigger difference between ceramic and Steel knives but you're going to have to leave that down in the comments because um you know we can only do so much in this video now I know what you're asking which knife cuts a tomato easier so I resharpened both knives to as sharp as I could get them and cut a tomato or it [Music] doesn't and after analyzing slow motion closeup tomato cutting footage I came to the dramatic conclusion that they're pretty much exactly the same and I can't tell the difference whatsoever now what about cile rope because for some reason the steel knife definitely seemed to cut through the sisile much easier than the ceramic and after analyzing the slow motion Ultra close-up footage I can't really tell you why now the only suspected reason that I have that this may have been the case is because the steel knife was indeed slightly sharper than the ceramic knife now I sharpened both of these knives to as sharp as I could possibly get them and in saying that I can actually get the steel knife sharper we can get this knife to a hair wiling Edge I am unable to get a hair weedling Edge on this knife right here now maybe that's because I don't have the correct Diamond progression to get that hair weedling Edge but I can get that same hair wedling edge with this knife with uh essentially one stone and one strap now the steel knife also did better even after both knives lost their initial high level sharpness and I believe this is simply due to a better geometry or a more acute angle we are able to achieve on the steel knife now remember this because this this kind of brings us to the conclusion which is that ceramic knives are very good for certain applications maybe you have a th000 feet of cardboard to cut and can't resharpen your knife at all in the middle of cutting in that case I'd pick a ceramic knife any day problem is still resharpening these because in order to resharpen this you do need expensive resin bonded Diamond Stones and again if you need to get this to an ultra extremely sharp very fine Edge you're going to need a couple of and these things are kind of expensive with a seal knife you can get away with sharpening this thing to an absolute hair Woodling edge with one stone and one drop in basically no time whatsoever that is not the case with ceramic knives resin bonded Diamond Stones are not cheap and Diamond shps are not cheap so you're going to have to spend some serious money in order to get this thing to the same level of sharpness as this knife and even when you get there that Apex is so is so fine and so delicate that the first literally the first cut you use it on you're going to end up with microchipping and it's not going to be that same a highlevel Apex sharpness anymore you're going to have Apex chipping with this it's just not strong enough to support those ultra fine geometries the other problem with ceramic is that it's very easily damaged I was very worried for some of these tests that I was going to snap this thing before I was done with it even some of the heavier cardboard that I cut uh was kind of y it it kind of felt like I probably shouldn't be doing this with this knife and I shudder to think at how hard it would be to remove larger chips in the edge of this knife than it would a regular old steel knife for food this is the thing that kind of gets me because you hear this all the time these things the Steel knives they ionize the food they oxidize the food faster uh in my opinion and in my test I just haven't found that to be the case I think in the vast majority of cases ceramic knives are generally going to be sharper than the Steel knives because they're relatively new fresh out of the box and sharp these things however are tossed in the drawer and they're not taken care of they're thrown in the dishwasher and the edges on these are even in my kitchen they're dull so you're going to see some food oxidizing performance segregation more with steel knives than you will with ceramic knives now I'm not saying that these things are completely useless what I am saying is that yes they are sort of fun to play around with depending on what it is that you're cutting but I think for the vast majority of people they may not provide the uh answer that you're looking for

Channel: OUTDOORS55

Views: 172,105

Keywords: knife sharpening, sharpening ceramic knives, sharpening ceramic knife, ceramic knife sharpening, sharpening, sharp, ceramic knife, how to sharpen, how to freehand sharpen, how to sharpen a ceramic knife, knife sharpening for beginner, freehand knife sharpening, knife sharpening with stone, how to sharpen ceramic, ceramic knife review, ceramic knife sharpening hard, why you can't sharpen a knife, ceramic knife test, ceramic knife edge retention

Id: FFEgg7OWsUk

Length: 14min 52sec (892 seconds)

Published: Sun Jul 14 2024