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  • FREE Learning- Why Cryo Treat Knives?

    Why Use Liquid Nitrogen? What Is Liquid Nitrogen? What Does It Do? How Do You Know It Does That? Will LN2 Fix a Bad Heat Treatment? People ask questions! And we're going to try and provide some answers today about one of the most misunderstood parts of heat treating knives- the cryogenic quench! WHAT IS LIQUID NITROGEN? The air we breathe is 78% gaseous nitrogen. It is all around us as you read this. So there's plenty of this element, but we need it to be liquid, and we need it in a container! This involves a process called "air liquification", which compresses and chills air or gaseous elements to the point where its constituent components separate and liquify. (carbon dioxide solidifies at -120F, nitrogen liquefies at -320F, oxygen at -297F, hydrogen at -423F). Knowing that, the liquifier can collect each liquified gas at a specific temperature, pretty much in its pure state. Much like a liquor still purifies and collects alcohol, except the temperatures are reversed! Then all that's necessary is to keep it cold, and pump it into my dewar. The vacuum insulated dewar I own insulates so well I only fill it about twice a year! Now remember, LN2 boils at -320F, so I think that's amazing! Why Use Liquid Nitrogen?- When a knife steel is heated to a certain point it changes to a softer, nonmagnetic phase called austenite. That "certain point" is modified by the carbon and other alloying content of the steel. Then as we quench the blade back to room temperature, it will pass a point called Ms "martensite start" , where the austenite begins to convert to the harder, stronger martensite(we want this conversion!). As the steel continues to cool is passes a point called Mf "martensite finish". Now, due to carbon content and other alloying, that Mf temperature can be below room temperature, below freezing, and sometimes even below dry ice temp.(dry ice, or solid CO2 is at least -120F). This can leave a percentage of the matrix as "retained austenite", which isn't a good thing for a variety of reasons. It is critical that the knife go straight from room temp to LN2. A delay of even a few minutes, or the sometimes recommended "snap temper" before LN2 offers an opportunity for the retained austenite to stabilize. Don't even check hardness, get your blade in the LN2 now! What Does LN2 Do?- This is the reason LN2 is the choice for cryo treating to insure Mf. It is cold enough to facilitate the conversion of retained austenite(RA) to hard martensite. There are reasons we want to convert this RA as soon as possible. Here are a few: 1) Retained Austenite makes the matrix of the steel softer. At levels around 20% or above, RA negatively affects the bulk hardness of the blade, hindering performance and sharpenability. 2) Under certain stresses, RA can spontaneously convert to untempered martensite. There is a valid reason we temper our knives after hardening. Untempered martensite is extremely brittle and prone to fracture. It has very low toughness. It is prone to chipping. It creates crack initiation points and stress risers. BAD JUJU! 3) RA negatively affects edge retention and sharpenability. Softer steels are harder to properly sharpen than harder ones. Soft steel doesn't want to take a crisp edge, doesn't want to let go of the burr or foil edge when stropping. And then the softer high RA knife gets dull many times faster. How Do You Know LN2 Does That?- There are a number of ways to accurately measure the effects of LN2 on steel. 1) Rockwell Hardness Tester. Running sample coupons before and after LN2, before and after LN2 AND tempering, and at different temperatures, and checking the hardness of each one is a knifemaker's way of verifying our processes are giving the results we expect! 2) Magnetic Resonance Since RA is nonmagnetic, a very accurate measurement can be made of how much RA is in a given piece of steel. While I do not have the means to conduct this test, there is plenty of research available to verify the theory. To the left here is a chart created by Dr Larrin Thomas, showing the effects of austenitizing temperature (hardening temp) and room temp quench vs home freezer vs LN2. It is easy to see that LN2 treated samples are 3.5 Rc points harder compared to room temperature, and 2.5 points harder compared to a home freezer treatment. That's quite a difference, and exactly why I use LN2 treatment on all knives at Keith Nix Knives. Will LN2 Fix A Bad Heat Treatment? - No, LN2 will NOT fix a bad heat treatment. If a custom knife is austenitized at too low a temp, it won't fully harden. LN2 cannot fix that. If the knife is austenitized at too high a temp, awful things can happen like explosive grain growth, too much carbon in solution, and so much excess RA even LN2 can't save the piece. So LN2 isn't a "fix" for anything. It is a logical continuation of a proper heat treatment, that can enhance desirable properties of the blade. Learn more about heat treating HERE! My desire is to make the very best knives I am capable of making. To get the geometry right for the knife and the tasks it will perform. The best support for that geometry is a hard steel matrix that supports the carbide structure of the steel, resists edge rolling and chipping, and sharpens easily. LN2 helps steels achieve all those properties. (Special Thanks to Dr Larrin Thomas of Knife Steel Nerds for his seemingly unending research and generous sharing of his findings with the knife making community.) More FREE Learning: What is Heat Treating? The Next Ultimate Knife Buyer's Guide How I Design and Make a Kitchen Knife What Makes a Good Chef's Knife? Knife Safety Tips Order Your Custom Knife from Keith Nix Knives Shop Now! keithnixknives@gmail.com 828-337-7836 Thanks for reading, Keith Keith Nix Knives

  • FREE Learning-What Makes a Good Hunting Knife?

    Keith Nix Knives FREE Learning!! Which Hunting Knife Style is Right For ME?? Everyone who hunts has a different answer to "what makes a good hunting Knife?" Part of that comes from what each hunter HUNTS, and part is likely family tradition. Some like big, beefy knives, others like thinner, shorter and more precise, agile blades. Bird hunters need a different blade, than bear, deer, or rabbit hunters. Folks who fish are hunters as well, and their blade needs are different still. A hunting knife is a tool, in fact a multi-tool. Typical classic designs try to make the hunting knife a tool to gut and clean a carcass, skin it, break it down into primal cuts, debone the primals, and fillet a few trout for dinner, after the same knife is used to process enough firewood to last all night. Of course no knife will do ALL that well, and it makes no sense to even try to make one. I do make a "classic" looking hunting knife(left), I make it thin enough to actually serve as a knife, and not a small axe like object for splitting firewood! It's a simple 4" - 4.5" drop point, with a handle that fits just right. This knife, "The Lautner", is available in any steel I stock I offer another blade, smaller and more agile than a standard hunter. A friend commissioned this blade and we designed it together, called "The Pig Skinner". He uses this 3" blade to skin the feral hogs he hunts in SC. Blade length can be increased to around 4" to accommodate your preferences. Named for the co-designer, this is "The Rollins". A third hunting knife I offer is a 5" fillet/skinning knife, or it can be stretched to 6 1/2-7" for a fillet/boning knife. Another great friend and I designed this one, around his love of an old fillet knife to skin deer. It's thin and flexible similar to a fillet knife with enough heft to still be useful skinning large game. This blade can be easily modified to your particular task. My thinking is that a "hunting knife" should actually be a "Hunting Set", with three or four specialized knives to do all the tasks needed to move game from the field to the frying pan or freezer. Do you have a need for a specialized hunting knife? Let's talk about it and get it built for you! More Free Learning: The Great Steel Debate Order Your Custom Knife from Keith Nix Knives Shop Now! keithnixknives@gmail.com 828-337-7836 Thanks for reading, Keith Keith Nix Knives

  • FREE Learning-26C3 Steel, The Chef's Dream

    Keith Nix Knives FREE Learning!! What is 26C3? 26C3 is a high carbon, low alloy non stainless steel. It's called 26C3 in the US, 1.2002 in Germany. 26C3 is produced by Uddeholmstrip for use as razor and scalpel blades. 26C3 has a very fine grain and carbide microstructure, and is exceptionally clean/pure. As such is capable of very high hardness (above 67HRc as-quenched) while maintaining good toughness. High Hardness Carbon Steel Kitchen Knives! Chefs and professional cooks who prefer carbon steel should definitely consider 26C3, which is very close in composition to Hitachi White #1, a well known Japanese blade steel. Both steels are extremely clean(low impurities), and have a very high carbon content with low alloying, allowing for extreme hardness in simple carbon steels. Hard, Yet TOUGH While high hardness is desirable, good toughness matters too. It is toughness that determines whether a blade will hold a keen edge or suffer chips. 26C3 holds up well in toughness comparisons, testing equal or better to more mainstream steels such as 1095, O1, M2, A2, and PSF27. I'll be running these chef's knives at 64-65 HRc, and tests show they'll be tougher than D2 at 60HRc! It's important to note here that this steel is NOT stainless. It will rust and develop pitting very quickly without proper maintenance!!! It will also develop a patina over time that many find attractive and quite desirable. Refer to "How to Care For Custom Knives" to learn more about the care of carbon steel knives. So if you're looking for a really hard, very fine grained custom chef's knife, we have the steel for you at Keith Nix Knives! Give me a call today at 828-337-7836... Dr Larrin Thomas over at Knife Steel Nerds has done quite a bit of testing on 26C3, measuring toughness characteristics at different hardnesses. Check out the article here! Other steels in stock here! How to Care for Your Custom Knife What's The Difference Between Cheap Knives and Custom? Order Your Custom Knife from Keith Nix Knives Shop Now! keithnixknives@gmail.com 828-337-7836 Thanks for reading, Keith Keith Nix Knives

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  • Quantifying Sharpness|FREE Learning Quantifying Sharpness | Free Learning | Keith Nix Knives

    Quantifying Sharpness Measuring The Sharpness Of Knives Professional Knife Sharpening Should Be a Measurable Process! You Can't Improve What You Don't Measure! Want Sharper Edges? You should expect professional results from the Professional Knife Sharpening near you! Since I began making and sharpening custom knives, one of the things I'm most satisfied with is the final edge I put on blades. My system and tools give precise, repeatable results and shaving sharp edges. BUT, these edges have to this point been tested using anecdotal measurements. For example, "does it shave hair? How easily?" or "Will it slice phonebook paper? How smoothly?" I wanted and instrument that would permit "Quantifying Sharpness"! This type of opinionated quality control doesn't sit well with me, being a machinist who is accustomed to measuring features with instruments that have .0001" (one ten thousandth of an inch) resolution. And since there was no finite measurement there was no process Quality Assurance or Quality Control other than shaving a nearly naked arm and slicing paper. "How hard is this edge pulling the hair it shaves?" is an anecdotal result, not a number I can share with other folks and have them KNOW how sharp my (your) edges are. I had been hoping to find something that could measure the sharpness of edges and put a NUMBER on that edge sharpness. Enter the new Edge On Up PT50A knife sharpness tester! From the website: "The standard used to determine the sharpness of knives is called the BESS: Brubacher Edge Sharpness Scale. This scale was developed by Mike Brubacher, owner of Edge-On-Up. He has a background in sensor and test development in various industries. In 2012 he started developing a standard that could measure the sharpness of knives and needles. The result is the BESS standard that was quickly adopted by experts and enthusiasts as one of the most user-friendly methods to determine the sharpness of a knife." This little instrument uses a certified and calibrated synthetic "wire" very similar to heavy fishing line, and a scale with 1 gram of resolution. The knife is pushed gently into the test media being held by the sharpness tester until the edge severs the "wire". The instrument reads the force required to cut the wire in grams, and that is the BESS score. What's more, the BESS score correlates directly to the edge radius (yes, radius. No edge can be sharpened to a perfect apex). So if your sharpened edge rates 85 BESS, it tells you the edge radius of that blade is 85 nanometers (a human hair diameter is 60,000-100,000 nm, or .002-.004") The BESS scale in the picture above gives comparative results. For example, there is a block between 250-350 on that scale, notated as "new high end cutlery edges". Another block between 150-200 says "utility razor blade". Another roughly between 25-75 is noted as "double edge razor blades". The knife I carry every day for a "box opener" needs a touch up, it just checked 208. To check out a quick little video from "Sharpening Supplies" of how simple this instrument is to operate, just click HERE! This is going to help me measure, control, and refine my sharpening process to the point where I'll be comfortable saying I'm delivering you custom kitchen knives that are as sharp as anyone in the country. Now I know I'll never get to the 50 gram level of a razor blade, and you shouldn't want me to. There are a couple of reasons. One, knives are much thicker than razor blades, with far more obtuse primary and secondary bevels, and that negatively affects the force required to cut the media. Two, an edge as keen and sharp as a razor would not hold up well in the kitchen, in the sheath, on the cutting board, or in the pocket. I'm thinking the right place to be for kitchen knives will be around the 125-175 mark (VERY sharp utility razor range), and probably about 150-200 for hard use outdoor knives. (Incidentally, that knife in my pocket at 208, still shaves but it pulls too much!) I'm pleased to address knife sharpening again in the quest to improve quality overall. I settled on my sharpening system, stones, and strops early on in the shop setup. Since then I haven't really looked at it, because I was slicing phone book paper and comfortably shaving arm hair, and the process is by hand and FAST!! If this gets us a few more points on the sharpness scale, I think we'll all be winners! To learn more about "How I Sharpen Your Knife", CLICK HERE! To Make an Appointment for Knife Sharpening Near you, CLick Here! ​ More FREE Learning: Knife Sharpening Q&A HERE! Quantifying Sharpness Part II Quantifying Sharpness Part III Knife Safety Tips Order Your Custom Knife From the Keith Nix Knives Shop Now! Sign Up For The Keith Nix Knives Newsletter! Click HERE! keithnixknives@gmail.com 828-337-7836 Thanks for reading, Keith Keith Nix Kniv es

  • Handle Materials Keith Nix Knives, Knife Handle Materials. Black Mountain NC

    Custom Handle Materials Customize your Handmade Knife With Your Choice of Handle Materials! Part of the pleasure of purchasing a custom handmade knife is getting to choose the unique handle material for that knife, and honestly most people will see the handle before they look at the blade. Being a custom knife maker in WNC, I try to source my handle materials locally, sometimes as locally as my own woodpile or a neighbor's dead dogwood! Some folks prefer wood, some prefer some other synthetic material, and all are available at Keith Nix Knives. Handle materials come in a variety of forms and colors, from impervious synthetics to natural woods. With all the choices available, it's easy to pick a color scheme for your kitchen set, or select a beautiful stained or dyed wood for your favorite sheath knife. Let's explore some of the available options. Or you can view some of the handles I've created by clicking HERE! Natural wood- This category is literally as diverse as the trees in the forest. Maple is a favorite, with all its figure types, from birds eye to flame, Ambrosia to spalted, burl to curly. But there are other woods including fruit woods like apple, mango, and cherry, nut woods such as oak, pecan, and walnut, and exotics like desert ironwood and rosewood. Lighter colored woods can be dyed a rainbow of colors to suit your personal taste while still showing the unique grain pattern of the wood itself. All the handle woods I use at Keith Nix Knives have been stabilized. That is a process where a polymer resin is forced into the wood using both vacuum and high pressure, then heated to harden the resin. The wood is then stable and resists changes due to humidity and temperature. Dyes can also be incorporated into the stabilizing resin, creating color that isn't on the wood, but IN the wood. G10- G-10 is the designation for a glass-based epoxy resin laminate. What that means is that you take a glass-based cloth (fiberglass, in other words), soak it in an epoxy resin, and then using heat and pressure compress it into the shape you want. This material is impervious to liquids, is a great choice for professional kitchens, and comes in a variety of colors and combinations of colors. It can be finished to satin or high gloss, and is quite low maintenance. Micarta- Micarta is compressed and laminated too, but it is primarily made from burlap, linen, paper, or canvas rather than glass. The laminate layers are bonded with a phenolic resin, which are then compressed with heat to become a hard material that is commonly found in many types of kitchen knives. Micarta generally offers more subdued colors and slightly better grip than G10. Micarta is not capable of a high gloss finish. Please contact me with any questions you might have about the handle materials for your custom knives! Visit the SHOP HERE! keithnixknives@gmail.com 828.337.7836 Call or Text Now! Email Me! Join our mailing list Email First Name Last Name Subscribe Thanks for subscribing!

  • Sharpening Knives|FREE Learning Keith Nix Knives | Sharpening Knives | FREE Learning

    Professional Knife Sharpening Articles From The FREE Learning Series Reliable local knife sharpening is hard to find, and Professional Knife Sharpening even harder. You'll find articles below telling you how I sharpen knives at Keith Nix Knives, and some tidbits on how you can be a better sharpener yourself! Just choose an article and click to read! How I Sharpen Your Knife -- Reliable, local, Professional Knife Sharpening Services seem to be hard to come by. Folks who don't sharpen their own knives need to find a professional knife sharpening service nearby, with a proven and repeatable process to make your knives sharp without damaging the steel. To find out how I do it, Click HERE! Quantifying Sharpness - Professional Knife Sharpening Service requires professional results, and professional results require quality control. Shaving sharp? ok... Paper cutting sharp? What KIND of paper? And there's the problem, the lack of a reliable way to measure sharpness. Until I found the "Edge On Up" Sharpness tester. Read about it HERE! Quantifying Sharpness II - A Professional Knife Sharpening Service should be able to provide professional results EVERY blade. After sharpening a number of knives and testing with the Edge On Up sharpness tester, I have some findings to share, with hopes that they might help others be better sharpeners! Check it out HERE! Quantifying Sharpness III - Professional Knife Sharpening with verifiable, measurable results! Three short videos to show you how the sharpness tester has benefitted your knives and my sharpening routine! See the short videos HERE! Learn To Sharpen - Knife Sharpening is considered by some to be a form of magic. Truth is, it's just a science or PROCESS based operation that you can learn to do with practice and patience. Learn more about the science HERE! Professional Knife Sharpening Questions Answered - S ome questions keep coming up about dull knives, knife sharpening, costs, what to expect from a Professional Knife Sharpening Service. Here's a whole page of Q&A to help you get answers! Click HERE!

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