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B. Norris

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Everything posted by B. Norris

  1. You are correct, the micro-bevel increases the durability of the edge and, for some knives that have very hard steel, is essential to prevent the edge from chipping out. Something I have recently learned the hard way on my own project! This video shows what is probably the most authentic method of sharpening. <iframe width="420" height="315" src="//www.youtube.com/embed/Qn3Kzujwdr0" frameborder="0" allowfullscreen></iframe> This video shows a few different things very well. They do not cover the micro-bevel in this episode but, they have many other sharpening videos, some of which discuss micro bevels. They do not seem to be working with a knife that has extremely hard edge steel, he talks about the edge bending over instead of chipping out. Also, he flattens the entire bevel instead of creating a slightly convex or "clamshell" edge. May be just personal preference, not sure entirely. <iframe width="560" height="315" src="//www.youtube.com/embed/pkqp7FjeLZg" frameborder="0" allowfullscreen></iframe> This video goes over the geometry of sharpening single bevel knives. <iframe width="560" height="315" src="//www.youtube.com/embed/WYZmtDlwDi4" frameborder="0" allowfullscreen></iframe> ~Bruce~
  2. "I was wondering if anyone has experience with these types of knives?" Currently going through my own project: Deba from Flea Market "But the blade also looks as though there was a primary edge ground on to it by someone sloppily. My understanding is that the original knife would not have this primary edge?" I am confused about what you are asking here. What do you mean by "primary edge"? What I see in your photos is a weld line, between the hard metal at the edge and the softer metal that makes up the rest of the blade. Below is an illustration of the cross-section of a Yanagi knife. Deba and Usuba will have the same general cross section but, the angle of the primary bevel, or blade road, from the illustration, will be slightly different. The picture that you posted, showing the cross section of the knife, at the heel, looks like it should with the blade road (or primary bevel, if you prefer) slightly convex blending into a micro bevel at the edge. The only things that look off are that it is perhaps a bit too convex and the "micro" bevel at the edge has gotten much larger than it should. The "flat" side of the blade should have a slight hollow grind, with only the very edges flattened on a stone during sharpening. The knife I am working on also had some similar dings on the spine. I used a small, light hammer to move the metal back into place while supporting the knife blade in my off hand. I did not want to set such a hard, brittle, knife directly on a hard anvil and start hitting it! Moving as much metal as possible, with the hammer, will save you hours of sanding later. Is the bolster horn or plastic? The answer will help determine the age of the knife. In either case, you should sand the scratches in the bolster out and polish it up again. The handle can be cleaned up with some #OOOO Steel Wool and some wax. The bolster could be epoxied back in place. Not sure what the wood, in the handle, of the knife is. Ho (magnolia), Chestnut and, yew are all traditional. ~Bruce~
  3. Peter's Heat Treat Inc. They seem to be associated with USA Knifemaker but, do not have Elmax or M390 listed under steels they handle. Would be worth contacting them to see for sure. Other knifemakers give good reviews of the service on some other forums. Paul Bos. It is not Paul Bos doing the work anymore but, instead his successor however, I've heard nothing but good about them. Texas Knifemaker's Supply. This is the "Services" page so heat treat is the second item down the page. Have not really heard anything about them good or bad. Pacific Metallurgical Inc. I did not know about these guys until I did a google search but, they have a page especially for knives and blades. ~Bruce~
  4. One last thing... The M390 has a reputation as being "fussier" to harden. The Elmax is slightly easier. Both require precise temperature controls, a furnace that heats evenly, and a programmable ramp controller on the furnace. The occasional user of these steels might be better off sending them out for heat treatment, especially considering the cryogenic requirements. ~Bruce~
  5. James, Check out this chart, on the website of Alpha Knife Supply. Elmax and M390 are almost the same steel. M390 has 1% more Vanadium and 0.6% Tungsten (Elmax has no Tungsten) other than that the M390 has 10 points less Silicon and 20 points more Carbon. Bohler-Uddeholm recently consolidated but, Elmax is listed as an Uddeholm steel and M390 as a Bohler steel. My take is they were competing to meet the same requirements before consolidating, it will be interesting to see if one of these two steels gets phased out in the future or if they both remain available. Elmax has a reputation as being tougher than the M390 but, with slightly less edge holding. Did you check out the links to PDF files, at the bottom of the page, on the previous link I gave you? The CATRA Test Results were pretty interesting and show how close the two steels are. The M390 has a slight edge in wear resistance, and that is at 1 RC point softer than the Elmax but, even at a higher RC the Elmax is tougher. In use, I think, it would be hard to tell the two steels apart. The big area where I see both of these steels having an advantage over other companies "super" steels is in the 3rd. generation powder. Having steels that are corrosion resistant, abrasion resistant, tough at high RC hardness, and able to take a very sharp edge, not to mention the improvement in finish quality... The whole package looks pretty good. That is why I would choose one of these two over the S35VN. I am not a stainless person myself, I prefer someone to care as much about my knives as I do in making them. However, these two steels tempt me because, I do not see them as requiring a sacrifice in keeness of edge or edge holding vs. plain carbon steels. That, combined with the much easier maintenance requirements, looks pretty good. When I eventually get around to making a cutlery set for my family use, this will be my steel of choice. It will keep me from losing my cool when I find a knife soaking in water, in the sink! Alpha Knife Supply does not have either Elmax or M390 listed on the blade steels page but, the page with the graph (that I linked to) insinuates that they sell it. You could contact them and find out. USA Knifemakers Supply has both Elmax and M390 listed although, many sizes are out of stock. ~Bruce~
  6. Different acids tend to reveal different things in the etch. Not to mention the same acid, at different dilutions. In general the weaker the acid, the more detail is revealed but, the more etch cycles it takes. I have had nothing but trouble putting the blade into a container of acid and now apply the acid to the blade. Try a few cycles of lemon juice on the knife you are working on. You can use fresh, or bottled. Just heat some up in the microwave, close to boiling, then dab it onto the blade with a cotton ball. Keep the blade wet, with the lemon juice, I usually use 15 minute cycles. It will be the same blade, with the same hamon but, the appearance will be subtly different. You will need to clean the oxides off the blade between etches. Generally, this is what powdered abrasives are for. Again, different abrasives will give different results. The main thing is to get all the black oxide off the metal, from the previous etch, without destroying any of the detail that the etch revealed. The black oxide is a by product of the chemical reaction of the acid and the metal and will slow down or stop the action of the acid if allowed to build up. That is why it is important to do a thorough job of removing it between etch cycles. The hard steel at the edge will resist the acid a bit more than the soft metal. A highly polished surface will also resist the acid a bit better, so if you polish just the hardened area, at the edge, the difference between the two will be accentuated a bit more. What type of backing block, or pad, that is used with the polish can change the results as well. One of the videos that I have seen, a hard, rubber, block was used and that seemed to work quite well. You want something hard enough to not conform to the surface and polish the bottom of any topography revealed by the acid but, it still has to be soft enough to hold the abrasive or polish. ~Bruce~
  7. "It is weird, we've all heard and known that the make of the steel doesn't make it sharp, but somehow, it still feels like Elmax gets crazy sharp very easily even though we sharpened it the same way we do other steels. Got no real explanation for it." The 3rd. generation powder metallurgy process utilizes powder, with a much smaller particle size. This limits the ability of the alloy to form large carbides. The large carbides tend to inhibit sharpening to a keen edge because, you either have to use a more obtuse angle to provide enough metal to support the carbides or you rip them free and create a ragged edge. In other words, no matter how much you sharpen, or what you use, it just doesn't seem to get sharp. This is the same reason the 3rd generation products are capable of taking a finer finish than previous generations of PM steel. ~Bruce~
  8. The point of the sand is to add thermal mass. A thick plate of steel, set in there, will do the same thing and is a lot less messy than sand! Especially if you have young children and they like to "help" in the shop. Ask me how I know this. I have a very similar, toaster, oven that I use for tempering myself. The trick is too keep an oven thermometer in there and watch it to know where the temperature peaks at. You will probably hit the temperatures you are looking for by simply blocking the exhaust out the top. ~Bruce~
  9. Off the top of my head, it seems there could be two issues. 1) Poor insulation. How is the oven insulated? Perhaps if you increased the efficiency of the insulation by either adding more insulation or using better insulation. Are there any areas of energy loss? Cracks, or seams, where you are loosing heat. Cooking ovens are often vented, on purpose, to allow moisture to escape. Are the vents oversized for your purpose? 2) Are the heating elements defective or insufficient? Do you have adequate power for the oven? Most ovens run off 220V and if yours plugs into a 110 outlet, I would say you have a problem! Last of all... Cooking ovens are usually horrible for tempering steel. The controls are simply not set tight enough to handle the task. Yes, you can make them work. Yes, you use what you have and they are affordable. That said, you would be better off building a tempering kiln with a programmable controller than putting more money into a kitchen oven. ~Bruce~
  10. Bohler-Udeholm, USA. High Performance Steel for Knives. Whatever you pick, I bet it's pricey, probably not forgeable, and takes a kiln (with electronic ramp controller) to heat treat. Not to mention, almost guaranteed to need a sub-zero cycle to precipitate retained austenite. Click the link at the bottom of the BUC page marked Phil Wilson Comments, to get another knifemakers perspective on some of these steels. ~Bruce~
  11. "Easy" is a very relative term. Yes, 1095 is easy compared to O1 and D2. 5160, however, is much easier and more forgiving than 1095. The thing to remember about 1095 is that it is hypereutectic, i.e. it has more carbon in the alloy than the iron can hold in solution. The extra carbon forms carbides, which are very hard, and add to the wear resistance of a steel. However, the carbon in steel is in solution and previous thermal treatments (like annealing) can move the carbon out of solution and precipitate it within the grain boundaries as carbides. When heating the steel up prior to quenching (austenitizing) the carbides take more time, at austenitizing temperatures to dissolve and allow the carbon back into solution.. That is where the recommendation to "soak" 1095 at temperature, prior to quenching, comes from. If not enough carbon is in solution when 1095 is quenched it can fail to harden or not harden to the full extent it is capable of. Raising the austenitizing temperature will allow the carbides to dissolve faster but, at the expense of grain growth, something that is not desirable in a tool because, it makes the steel more brittle than an object with a finer grain - at the same RC hardness! Assuming that your heat treatment is spot on, tempering at 400 degrees Fahrenheit would yield a RC hardness of around 62-63. Quite a bit harder than the usual recommendation of RC 58! However, heat treating, by eye, in a forge, using a magnet to test for austenitic - my instinct is that the steel got a bit hot at some point and you have a larger grain than is optimal. This would make the 1095 easier to harden and make for a blade that is, slightly, more brittle, at the same RC hardness, than a blade with finer grain. In your shoes, I would harden a piece of scrap in the same fashion then break it and try to determine if the grain was acceptable or not. My other recommendation would be to temper hotter. Here is a link to a chart (down the page a bit) of tempering temperatures and approximate hardness of 1095. Link. ~Bruce~
  12. Somewhat odd that the horn and table are in such good shape while the face and the front edge are so rough. Nice score on the anvil. Use it for a few years before deciding to "repair" it. ~Bruce~
  13. Can you just heat the surface of the wax, until it gets tacky, and use that stickiness to adhere your pattern? ~Bruce~
  14. Many of the very old French anvils share this feature. They call them "piggy" anvils! ~Bruce~
  15. Mark, I made a blackjack (leather mug) and finished the exterior with beeswax. So far I am very happy with it and find the longevity of the finish and the degree of water resistance superior to anything else I've used on leather. My method was to put the oven on low, leave the door cracked, put the mug in the oven, and then pull it out and wipe it with some beeswax. The wax would melt and wet the leather, from there I put it back in the oven and repeated until the leather would not absorb any more wax. ~Bruce~
  16. In another thread on the forum, I linked to A Short Essay about Gaucho Knives. The image below is taken from the article along with the caption. So, this is a practical solution to an engineering or aesthetic problem encountered by cutlers in the past and addressed in a similar fashion? Photo 3. Empatilladura. A reinforcement has been soldered to the handle-crossguard assembly to strengthen the union of hilt to blade. Generally present in long-bladed facones and dagas. ~Bruce~
  17. i think you're right and that my problem involved pressing with both hands on either side of the blade causing the metal to bow away from the grinder. pressing on the cork with my thumb directly over the platen was a definite improvement. Sometimes I will grab the backside of the platen with my hand and then use my thumb to press the blade into the belt. Only works until the platen heats up! Until then, it sure works well. ~Bruce~
  18. B. Norris

    facón

    Here is a link to a Google Image Search of "Gaucho Criollo Knife" Here is an essay about the history of these knives: A Short Essay about Gaucho Knives. Some defining characteristics of modern gaucho knives are: an integral bolster, long pointy blade, drop from the handle to the heel of the blade like a chef's knife, a high degree of finish and ornamentation. ~Bruce~
  19. Thanks for the link. I used to have a set of King waterstones but, they vanished with my first wife. Below is a picture of another Japanese knife showing the direction I want to take with the handle. Thinking about a wood sheath too but, in Yew also. ~Bruce~
  20. Judging from this knife, you must have received some valuable feedback at the California Hammer-In. The workmanship I see here is leaps and bounds beyond what you have posted in the past. The profile of this knife is very nice and shows vast improvement. That said, I am re-posting your pictures, with some areas circled that you could do better at. Overall, I think you need to spend more time, at each grit of the finishing process, and make sure that all scratches from the previous grit are gone. My other, general, critique is that you are rounding over the lines of your grind. A nice sharp line, at the transition of the bevel to the flats would be an improvement. The same advice applies to your plunge cuts. Last of all, you should consider finishing/staining the maple of your handle. The technique to do so has been covered several times before on the Bladesmith's Forum: Maple Stains. ~Bruce~
  21. A set of these cheap ones from Harbor Freight. A solid (no holes, just flat surface) double sided, 600/1200 grit, diamond plate, that is 1/4" thick and about the size of a credit card. I bought it at Cabela's years ago but, they no longer carry it. Too bad. Last of all a medium grit, ceramic, stone from Spyderco. Far right, in dark blue case, in the picture. ~Bruce~
  22. Looking at the landscape that shaped me... Explains quite a bit - lots of extremes! ~Bruce~
  23. What size 1095 stock are you starting with? The forged blade, in your hand, looks smaller than the drawing. Was this because the drawing is larger than life or??? Did you want a whittle tang knife or was the drawing showing a full tang? What I am getting at, is that if what you did does not match your initial concept. Try again and leave this attempt to be finished later. In the short run, it sucks but, in the long run you will be thankful. ~Bruce~
  24. Looking good there! Don't have too much fun testing it out... Tends to leave scars! ~Bruce~
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