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  • First time sharpening - help needed

    Hello,

    Before I start, please note that I have watched many YouTube tutorials and read many articles about sharpening whittling knife, yet I am not successful...

    Attached pictures and video are of my whittling knife that I have tried to sharpen for the first time as it become extremely dull. The process was: wet sandpaper grit 320 -> 500 -> 800 -> 1000 -> 1500 -> 2000 -> leather strop with compound. After grit 320 and 500 I could feel that edge is really sharp and patterns on the edge after sharpening were straight, without any bumps and downs - if I went with edge on my skin it would make a sharp cut (like with paper edge). After that something changed and i could no longer feel this sharpness after 800/1000 and so on. Finally the blade is like on pictures, not sharp and kinda dull... I spent on this 2 hours and I am devastated that I can not perform such simple thing really.

    Yes, I kept the blade all the time flat on sandpaper.

    Please, could you please help me find what I do wrong? Maybe I should not go for higher grits and stick to 500/800 as final? Would that be okay?

    Link to video (hope you can access that):
    https://photos.google.com/share/AF1Q...4tNnJjR2xFcDhB

    Here you can see bumps and bounces on the edge, it's like moving stairs under light.
    image.png
    image.png
    ​Here visible is strange pattern.
    image.png
    image.png
    image.png
    ​​image.png

  • #2
    First, before sharpening, look at the edge of the blade head on and turn the blade ever so slightly. If you see any white line or glints of white along the blade's edge, then it needs to be sharpened. The thicker the line or the bigger the white glints (dings in the blade's edge), the more sharpening you'll probably need to do. Use a permanent marker to mark the bevel and the edge of the blade. Once you've started the sharpening, look at the blade to see how much ink you have removed, if it is all gone or if it hasn't been removed evenly across the blade.

    Second, once you get a wire edge, and then lose it on the next grit of paper, you need to keep going with the same grit until you get the wire edge back again. Don't move on to the next grit until you get the wire edge back.

    Think of it as forming a V. If you have a wire edge, you have a V where the point of the v is prolonged--like an upside down Y. If you don't have a V, then you probably have more of a flared U. So, you keep going until you get that wire edge.

    This explanation is how I see it in my mind. Hope it helps.

    BTW--after sharpening the blade, the stroping only cleans off what you don't want on the edge and the blade, i.e. you're polishing it clean of loose metal, sandpaper grit, dirt, etc. When you strop while woodcarving, you are cleaning the wood fibers, oil, dirt, etc off the edge of the blade and polishing the blade itself clean. In either case, you are reducing the "drag" of the blade when it goes through the wood. So the stooping should only be maybe 5-10 strokes to each side.

    Also, I read somewhere that it doesn't matter whether you use water. I never liked the mess. So, I started sharpening dry and I find it a bit easier--less waste of sandpaper, and a "cleaner" process--still the black residue but it's not running off, dripping etc. I don't think it matters as far as the sharpening of the blade. So just my thoughts on that.

    Good luck!

    BobL

    Comment


    • #3
      Thank you so much for tips, will try to do that today resharpening knife again...

      Just one more question, how long should strap of wet sandpaper last? I mean, after 5-10 minutes of sharpening the grit feels like it has worn off - should I keep going on such strap or do I have to take new one each time I sharp knife?

      Comment


      • #4
        What do back the sandpaper with? When I used sandpaper I attached it to granite tiles and I used it dry. It looks like somehow your sandpaper was secured unevenly. I found sandpaper messy and overtime expensive and never use it now. I now use DTM diamond plates or oil stones. I also have beaver craft knives which came sharp. As long as you remember to strop with compound every half hour you should never need to re-sharpen with these lower grits unless you chip or otherwise damage the knife. (Green is usually about 3000 grit.) But if you need to resherpen with plates, stones or paper with each grit sharpen each side until you can feel a wire burr on the the other side. I suggest you get a jeweler's loupe and take a good look at the edge. I be you will see that it is flat and not sharp. I would worry about that and not the bumps and bounces. However it seems to me that either the surface where you mounted the 800+ sandpaper was not clean, there was debris left on the knife from the lower grits, the grit on the sandpaper was loose or you got lazy at the higher grits and rolled the edge. By the way, I would have done 500-1000-2000.
        You only need to double each time. (Actually given what I can get it would be 400-800-1500.)
        Sharpening is not so easy .... until to get it figured out.

        Comment


        • #5
          The waves are a result of the manufacturer grinding the edge with a grinder. You are smoothing out this irregularity when you started sharpening. The reason it seemed sharp was because you sanded down the high points in the wave. Think about a serrated knife on a lot smaller scale. Serrated knives feel sharp because you touch the points, Keep after it! Use the advice and you'll be good at it in no time.

          Steve

          Steve

          Comment


          • #6
            Originally posted by Combo Prof View Post
            What do back the sandpaper with? When I used sandpaper I attached it to granite tiles and I used it dry. It looks like somehow your sandpaper was secured unevenly. I found sandpaper messy and overtime expensive and never use it now. I now use DTM diamond plates or oil stones. I also have beaver craft knives which came sharp. As long as you remember to strop with compound every half hour you should never need to re-sharpen with these lower grits unless you chip or otherwise damage the knife. (Green is usually about 3000 grit.) But if you need to resherpen with plates, stones or paper with each grit sharpen each side until you can feel a wire burr on the the other side. I suggest you get a jeweler's loupe and take a good look at the edge. I be you will see that it is flat and not sharp. I would worry about that and not the bumps and bounces. However it seems to me that either the surface where you mounted the 800+ sandpaper was not clean, there was debris left on the knife from the lower grits, the grit on the sandpaper was loose or you got lazy at the higher grits and rolled the edge. By the way, I would have done 500-1000-2000.
            You only need to double each time. (Actually given what I can get it would be 400-800-1500.)
            Sharpening is not so easy .... until to get it figured out.
            Well, my bad luck I read your post just after i gave up a moment ago trying to sharpen my knife...

            I found the issue with bumps and bounces and it is exactly as you say - I mount sandpaper straps with clamps to my desk since I do not have any dedicated space for this hobby and the desk's surface is not "flat" but has delicate wooden texture, hence the effect on higher grits. Picture of my straps attached and how they look like - maybe someone will find it helpful.

            As for your tip to get jeweler's loupe - I do not know why I did not think o use my loupes as I have them (watchmaker's ones). I feel so stupid to be honest...

            I remember first time using Beaver Craft knife and it was extremely sharp, but due to my lack of knowledge after I got it I made couple of walking sticks with it and smaller carvings without any stropping. This is why I have to sharpen it now with lower grits as it became extremely dull.

            The grits I have are 240 - 320 - 500 - 800 - 1000 - 1500 and 2000, could you please advise what numbers should I use in current state of the knife? I was thinking to make it once and for good since I have found issues and to go from 320 -> 500 -> 1000 -> 1500 as you suggest skipping most aggressive (240) and medium 800. Do you think that would work?

            Thank you for helping me out, I do really appreciate this!

            image.png

            UPDATE

            Thank you so much, after understanding it all again with your help I decided to go with 320 -> 500 -> 1000 -> 1500 -> 2000 -> leather strop. Made really precise grinding (even grinded my thumb nail to the blood by accident) and I am happy to tell you that I have successfully sharpened my knife! Could not do that without your help

            Looks like new and most important - cuts pretty well. I am truly happy to learn this properly, many hours well spent.

            image.png
            image.png​​
            Last edited by Dzwiedz; 09-18-2022, 03:03 PM.

            Comment


            • #7
              Look around for a flat piece of glazed tile, or even a piece of glass to attach your sandpaper to. You can hold the sandpaper down with masking tape (painter's tape). I'll repeat BobL's advice. Use a permanent marker on the blade - you don't have to cover it - just 3 or 4 strokes across the blade. Then make a couple of passes on the sandpaper or strop and see if you are removing the marker ink evenly across the width of the blade. If not, adjust how you hold the knife and try again.

              Once you get through with the sandpaper, you need to strop the blade. I don't have to use sandpaper or a stone unless I damage the edge of my blade. I just strop every 15-30 minutes. What kind of strop are you using? I recommend using a thin piece of cardboard from a cereal box, taped down to the tile or piece of glass, with stropping compound rubbed on it like a crayon. The stropping compound I use is 0.5 micron grit. Mine is the green (Chromium oxide) kind, and I also have the white one from Flexcut - both work. Leather strops are not as good as thin cardboard, as the leather compresses as you pull the blade along it, and then it expands right as the knife edge passes. This results in rounding the knife edge, so instead of a 12 degree included angle at the edge, you'll eventually end up with a larger angle such as 20-30 degrees. Makes it harder to cut the wood. As you use the strop, the compound on it will turn black. This is good, as the black are microscopic pieces of steel that the compound has removed from the blade. I have even seen people use a flat piece of MDF and rub the compound directly on the wood, although you take a chance that some sanding grit may remain on the MDF from the manufacturing process.

              Claude

              My FaceBook Page: https://www.facebook.com/ClaudesWoodCarving/
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              My Instagram Page: https://www.instagram.com/claudeswoodcarving/
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              Comment


              • #8
                Thanks Claude, I will read about this cardboard thing versus classic leather strop. I thought that leather strops are kind of a standard as I see everyone using them (eg. on YouTube). I personally use one bought from Beaver Craft with green compound also from that company - no idea if it is any specific, just generic one I guess. And yes, it does turn blackish or is removed completely from leather, maybe I am pushing the blade too hard against leather? Compound itself is extremely "sticky" and hard. I mount this leather strap same way as sandpaper straps with claps to the desk.

                Comment


                • Claude
                  Claude commented
                  Editing a comment
                  I'd suggest using a "light touch" when stropping on leather. Don't press down hard, as that compresses the leather. My grandfather was a barber (among other occupations) and used the barber's leather strop. I remember that he didn't press down much at all when stropping his razors on it.

              • #9
                Pull strokes only, never push the sharp edge into the abrasive.

                The black color is the metal, the tool steel, particles, that you are cutting off with the abrasive.
                Just evidence that the process is working. There's no harm done to anything.

                The green is Chromium Oxide that is a standard honing compound, mixed with wax, and used across industry. The wax will eventually soften a leather strop = useless. But consider the wax as a bit of a rust preventative. Instead, I have used hard card stock for many years. Many centuries ago, carvers and carpenters needed a hard flat surface for sharpening their tools. The only flat, hard thing that you can name that they had in any economic quantity is leather.

                You learn to do what works for you. For my elbow and D adzes, I use a tennis ball to sharpen and hone the curved edges.
                Brian T

                Comment


                • #10
                  Originally posted by Dzwiedz View Post
                  UPDATE

                  Thank you so much, after understanding it all again with your help I decided to go with 320 -> 500 -> 1000 -> 1500 -> 2000 -> leather strop. Made really precise grinding (even grinded my thumb nail to the blood by accident) and I am happy to tell you that I have successfully sharpened my knife! Could not do that without your help

                  Looks like new and most important - cuts pretty well. I am truly happy to learn this properly, many hours well spent.
                  I'm glad you got it worked out. BTW I did not like the compound I got from Beaver craft. And I have more than a lifetime of green sitting in my shop so I used that. I like the Beaver Craft leather strop and glued two of them to each side of a piece of baltic birch plywood. Smooth side up please. Use a hair blower/dryer I heat the green wax and the leather and rub it on to the leather. I only did one side and left the otherside plane leather. I strop about 15-20 times each side of the knife on the green side and follow with about 5 times on the plane side. (I am not yet convinced about the cardboard vs leather argument. Craftsman have been using leather for centuries.)

                  Comment


                  • Claude
                    Claude commented
                    Editing a comment
                    <grin> Cereal box cardboard didn't exist centuries ago...

                • #11
                  Great advice and refresher information for all!

                  Comment


                  • #12
                    Cardboard vs leather.

                    In a very bright light, I could see the leather deform, get pressed down, as the tool edge passed over.
                    I decided that the wax in the honing compound had softened my expensive leather strop over the years. The result was that the tool edge was being rounded over as the leather rebounded.

                    I quit.

                    In this day and time, we have all sorts of hard flat surfaces to use for abrasive support.
                    I'm using 600/800/1000/1200/1500 grits of 3M fine automotive finishing wet and dry sandpapers.
                    Just stuck to a countertop ceramic tile with dabs of masking tape. Economical and easy to replace with fresh/new. Last step is chrome green scribbled on some kind of hard card stock (file card, cereal box, etc).

                    For me, that change in support was the solution to the puzzle = excellent swift results.

                    Then maybe 10 years ago, I went off to explore the variety and shapes of the crooked knives and adzes that are used by First Nations carvers here in the Pacific Northwest. The sandpapers and thin card stock could be wrapped around cylinder mandrels of any sort: dowels, pipe, etc.
                    The mechanics of the sharpening process are reversed = the tool is held stationary and the abrasive moves. It's a little harder to hold the angle in repetition but you soon get the hang of it.
                    Brian T

                    Comment


                    • #13
                      I would like to update you once again.

                      I tried to whittle a little and after a moment my blade started to be dull, cuts were difficult and it was more of a scrapping than whittling. I could not do a proper stop cut - the blade just did not go into the wood no matter how hard I pressed and at which angle etc.

                      I examined the blade under x10 loupe and I could see small imperfections of the edge (rolls?) and noticed some possible chips of the edge and definitely last part of the tip. Without the loupe blade looks perfect, light reflection is equal and flat along whole cutting surface. I cannot feel anything under my finder when moving along the edge or across - no sharpness, although I would not try to cut my skin with some force applied.

                      Basically, I do not know, is the wood I use too hard or something is not okay with it? Is my knife bad because I made many mistakes by trying to sharpen the blade? Maybe I simply lack skill and cannot handle slicing the wood properly? I feel overwhelmed and resigned by such small thing.

                      I am starting to think that maybe it would be good idea to order a Flexcut number 3 knife (detail?) and try it to check if there is a difference in cutting and sharpness compared to my currect BeaverCraft? If it cuts better, well, I probably killed BeaverCraft. If not, maybe wood, maybe skills... What do you think? I am attaching some pictures of wood I tried to whittle today.

                      Also, worried that if I buy Flexcut knife I will be scared to even try to sharpen it in the future not to kill it. So sorry for bothering you with this, but I am trying to mimic a lot of things from YouTube and it simply never looks or is the way it is showed, hence I must be doing something wrong or my tools are bad because of my actions. Just trying to understand what's happening and improve.

                      I marked a place when it is clearly visible that simple cut along the grain on the edge of wood piece left some marks, strange thing is the other side of blade has not been leaving them.
                      image.pngimage.png

                      Here you can see how cuts are not clean, leaving some "whiteish" spots and traces:
                      image.pngimage.png

                      UPDATE

                      ​​​​I found BeaverCraft knife that I got as gratis once and has been not used since. It cuts perfectly clean, it is sharp even against the end grain. It makes stop cuts possible.

                      I have no idea what am I doing wrong, will try to regrind the whole knife again starting from sandpaper 240 slowly up to 2000... Will change surface from under the sandpaper to flat glazed tile. To be honest I am kinda sad that I cannot do this simple thing.
                      Last edited by Dzwiedz; 09-22-2022, 08:51 AM.

                      Comment


                      • #14
                        Please do not give up. Some wood is easier to make a stop cut in than other woods. When I am using a harder wood, I know the stop cut cannot me made in one pass. It sometimes takes 4-5 passes to get appreciable depth to the stop cut. I then cut up to the stop cut, then next I go back and make 2-3 more cuts along the stop cut. then cut up to it.

                        When regrinding a blade, draw some lines across the blade with a permanent marker. After a couple of passes at grinding, look at the blade and see if the marker ink is gone uniformly, or only along a certain area, then adjust the way you hold the knife so that the marker ink disappears where you want it to. You can use the loupe to check the ink removal as well.

                        I also have found that when I strop my knives, I press my forefinger on the flat of the blade to hold the blade flat against the strop as I pull the blade along. 10-15 passes on one side, then turn the blade over and the same number on the other side, again with my forefinger holding blade down. I am not applying much pressure either - I let the compound do the work.

                        Flexcut knives are not bad, but they are more difficult to cut wood with than thinner blades. Here is a chart I made that shows the blade thickness, included angles, etc. My favorite blade is the Goodman blade. The thinness of the blade makes it cut through the wood like butter (almost!).
                        Knife blade thickness.jpg

                        The modification to the KN-13 was to have it flat-ground to get rid of the "shoulder" on the factory blade. As you can see, this decreased the included angle and made the knife much more able to easily cut the softer woods. Allen Goodman was the one who modified my KN-13 for me. He was providing sharpening services at one of the Renegade Rendezvous classes in Tennessee, so I asked him to modify the blade for me.

                        Claude
                        My FaceBook Page: https://www.facebook.com/ClaudesWoodCarving/
                        My Pinterest Page: https://www.pinterest.com/cfreaner/
                        My Instagram Page: https://www.instagram.com/claudeswoodcarving/
                        My ETSY Shop: https://www.etsy.com/shop/ClaudesWoodcarving

                        Comment


                        • #15
                          Originally posted by Claude View Post
                          When regrinding a blade, draw some lines across the blade with a permanent marker. After a couple of passes at grinding, look at the blade and see if the marker ink is gone uniformly, or only along a certain area, then adjust the way you hold the knife so that the marker ink disappears where you want it to. You can use the loupe to check the ink removal as well.

                          Claude
                          I tried today, basically whole day (around 5-6 hours). Wet sandpaper with grit 240. I simply cannot make it sharp and create wire edge. Attached pictures are my current blade.

                          This is pretty much self explanatory... No matter if I grind on grit 240 I simply cannot make those marked crossed disappear to create flat surface until the edge. Marked in yellow is amount of metal taken out just today and still, no effect. I do really keep the side flat as you can see above the black crosses it is really flat and with even surface.
                          image.png
                          Another side is much better as there is only small amount of black marker left near the edge and some surface above it keeps rounding no matter how "flat" I keep the whole blade - you can see the rest of the blade is even and flat with even grain lines.
                          image.png

                          I do not even want to think about rounded edge or chisels which I also happen to have... Of course I can change the angle a little and grind the part near edge but it will create a bulge or whatever it is called (not flat but rounded, bumpy).

                          I simply have no more strength and I start to think I may be uncapable of sharpening straight blade, I feel frustrated. I do not see a way to follow this hobby if I cannot do such simple thing really, I am not gonna buy a knife each time it gets dull. I am stuck, completely. I feel dumb and I have no idea what to do next.

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