Gases are released in the quench and would form a "trap" around the steel unless you keep them moving for a minute or so. Many people will say a properly heat treated steel should not need any cryo treatment as it only “makes up for a poor heat treat” This sounds good but isn’t necessarily true. Material that has been forged could probably benefit. We like hanging the blades from a coat hanger in the cryo tank. After removing and cooled check hardness. Done. Q2:  Why do you leave blades in the foil to plate quench them. When the package has cooled enough for handling, remove the foil. These steels don't need a long soak time. Uneven carbide size and distribution lowers the cutting performance. Draw temper to desired hardness The oil should be warm, thin quenching oil that contains a safe flash point. Q9:  321SS foil is much cheaper. The steel will decarburize and you will not know until you etch it. Below are listed the approximate Rockwell Hardness achieved at the various temperatures. If you see a warp, now is the time to bend it slightly back to being straight and it should take. 4. Q11:  How do I know if my oven is accurate for temperature? Wrap blades in tool wrap. You can experiment for other hardness's but 61 is a very good target for these steels. All three of these names refer to a fireproof box that gets hot. The soul is born in the furnace, because the heat treating brings out the highest qualities of … This is what it looks like when I "heat treat" a blade. Always exercise care and precaution. The heat treatment of 52100 is different than that of many of the other alloy steels, including 5180, in that the hardening temperature controls the amount of Carbon that dissolves in the austenite - the condition of steel at high temperature where it is a solid solution of Iron and Carbon. Quenching is performed in either light oil (we recommend olive old with clove quenches well we find), or a standard quenching oil. 7. The blade should be quenched either point first or spine first in order to minimize the chance of cracking or warping. You should have approx. Black walnut custom knife handle – from my hero’s walnut tree, Full Sized Nessmuk with Multi Carry Sheath, Mid Sized Kephart with Tiger Maple Scales. A propane (or MAPP gas) torch played evenly along the blade will get the job done. Cooling slower in the forge works better but cooking in the vermiculite works fairly well also. 3. It won’t take very long at all. You should slowly agitate the blade up and down or side to side along the thin edge. Most high carbon steels are generally not cryo treated as the benefit to carbon steels is usually not as significant as it is with the newer super stainless steels. This will be on the cutting edge. This should be achieved between 1,400 & 1,500 degrees F. Be careful not to overheat. Heat the blades to 500°F, remove from furnace and roll them in a tray of compound. Do not forge below 1500°F (815°C). This rack will hold the blades in an upright position for minimizing warpage. 60 RC. You will see somewhere, a lot of places in fact, that the steel really needs to be cooled off at a high rate, like 1 to 2 seconds and that is absolutely true. Use a plastic or glass container to hold this solution DO NOT use a metal container. That said, use this as a guide to heat treating, but not a verbatim blow-by-blow. You should have a wire basket inside the quench tank. Random with CPM420-V and 440-V Heat Treat Procedure 2. Quench 300 350 400 450 500 550 600 650 The low tempering temperatures won’t cause you any scale or oxide problems anyway. Wrap blades in heat treat foil. Heating coals evenly will ensure proper heating of a knife blade. Some knifemakers have recommended a 1475°F austenitize. Temper twice at 2 hours each allowing the steel to cool back to room temperature between cycles. Handle your blade carefully at this stage or you may end up with a cracked or broken blade. Most high carbon steels are generally not cryo treated as the benefit to carbon steels is usually not as significant as it is with the newer super stainless steels. Having said all that, most don’t cryo treat carbon steels but you can if you want. Special Thanks to Mick Koval (R.I.P) of Koval Knives for this Information. Air quenching, Oil quenching, Salt baths, Vacuum furnaces…. The golden straw color you see in the picture below is the sign of a proper heat treat. Do not agitate side to side as the soft metal can actually warp from the fluid being cooler on side versus the other. 2. If you are producing 20 knives a year and send them out for heat treating at $15 a knife, your annual cost is $300. As a rule of thumb there should be a gallon of oil for each pound of steel. The bottom line is that a knife is a tool and it needs to be able to function. More info below⬇️Beginner knife making steel video. You may double wrap fro extra assurance of locking out all oxygen. Heat blade to between 1,400 & 1,500 degrees F. This steel gets double tempered at 400F degree for about RHC60. Basically, heat it in your forge or oven and let it air cool. You want to temper it as soon as it gets to room temperature. It is up to you to abide by any and all laws applicable to you and your location. We only ever use material sourced from Europe’s finest metal manufacturers and offer our own knife heat treatment service to guarantee the best quality blades. Once there is little or no attraction between the blade and magnet the blade will have reached the proper temperature and is ready to quench. Evenheats' Set-Pro control can be programmed to automatically soak, for any amount of time desired, once temperature is reached. Make sure the floor around your oven is free from combustibles and please resist the urge to catch the falling blade. Heat to 1500, soak 10 minutes. 500F yields approximately 59-60RC which is where most will want this steel. The next morning, they will be in the range of RHC63+. Make sure all the oil is cleaned from the blade or your house will smell like oily smoke and your knife making career may be cut short by the boss of the kitchen. Evenheats' Set-Pro control can be programmed to automatically soak, for any amount of time desired, once temperature is reached. Same wrap – Harden at 1900F degrees and only about 15 minutes at temperature – then plate quench and cryo as above. Once the blade is totally dry you are ready to dip it in to the solution. Oil. 50% PCB Etchant Solution (available at Radio Shack®) & mix with 50% White Vinegar. Keep washing the blade until no more black carbon is coming off. Always put them in the envelope the same way – so you can put them in spine down and pull them out by the handle, instead of the tip. First segment: ramp as fast as possible (9999) to 1975 degrees F, hold for 5 mins. Normalizing: Heat to 1575°F (855°C). A softer blade, say 57RC, will chip less, be easier to sharpen and will bend quite a bit more before snapping. It should be avoided. 1080 or 1084 is a high carbon steel with .80% carbon (the 80 in 1080) and is proven, good quality knife steel with good edge retention. The road to success is to evenly heat the metal. Put your knife in the pile of charcoal and heat it up. Check harness. We have drawn from various sources, including Crucible data sheets, other steel suppliers and postings on Blade Forums as well as a good dose of personal experience. After placing the blades in the furnace, heat to 1850°F. Same wrap – same temperature (1950F) - same soak time – same plate quench – same cryo as 154CM above. A surface fire on quench oil is not the end of the world. Dry Ice or Liquid Nitrogen work equally well. You should have approx. Note: Rob really nailed the question of using a pyrometric cone for temperature measurement. AISI D-2 Heat Treat Procedure For consistent results, you should keep your blades in a more or less consistent place in the chamber. Heat Treating Stainless Blade Steels at Ranger Original Handcrafted Knives The heat treat temperatures for the random with CPM 440-V and 420-V core will be different. Generally, in a forge, this means heating it until a magnet doesn’t stick and then “just a little more” to get the extra heat into the steel past non-magnetic. Be ready for that. The grate or wire mesh will allow air to circulate under the blades as well as around them for uniform quenching. Poor Man’s heat treating of 1095 – 1080 - 1084, Midwest Knifemakers Supply, LLC at www.USAKnifemaker.com, Knife Dogs Knife Forum at www.KnifeDogs.com. This is amazingly easy. Note when heat treating multiple blades keep ample space between each blade for proper air circulation. Done. Just the blade is good enough. Evenheats' Set-Pro control can be programmed to automatically soak, for any amount of time desired, once temperature is reached. 1095 is considered slightly “fussier” about heat treating than say 1080 or 5160. Try to get the heat color evenly across the blade. After placing the blades in the furnace heat to 1850°F. Drawing, or tempering the blade is done by heating the steel in an oven. A9:  Depending on who you talk to, the 321 is rated to something between 1800 - 2000 degrees. Here are our recipes. The next step is to oil your blade using good quality gun oil. Knife Kiln vs. You will read about guys using acetone in dry ice. Forty years ago when I began making knives I wanted to make beautiful knives that met the highest levels of function possible. While the blades remain cooling set the furnace at 375°F. This is all part of the hardening process of the blade. Pile up some charcoal in your BBQ and get them going good. Some guys use lime instead of vermiculite. You can even use water and something called “interrupted quench” but let’s leave that for another time. If you have other work you want done, I use a half size trash can full of vermiculite. 1095 There are no "short-cuts" for proper heat treating. It will adhere to the steel and form an air tight blade. Tempering: If you did everything right quenching, your steel is around 66RC and fragile as glass. Heat treating has obvious hazards. IMPORTANT - It is very important that the blades enter the oil quench as quickly as possible after leaving the furnace! Do not put any paper in foil. Hint; Avoid getting closer to heating coils than necessary. Hardness 62 61 59 58 56 55 54 53 Normalizing steel allows the crystalline structure to be reset and resets the carbides back to uniformity. We have had a number of people ask us for our “secrets” about heat treating knife blades. This means the final hardness should be around 62-63. When the magnet doesn’t stick any more, give it a minute more of heat and then quickly plunge the blade into your quench oil. Q3:  Why do you remove the blades from the envelope before cryo? In short, bring it to critical temperature, quench it in vegetable oil, then temper it in an toaster oven or regular kitchen oven for one hour at 400˚. Cras posuere imperdiet lorem, in aliquam urn. Generally, steel that comes in bar form from a mill is often annealed and probably doesn’t need to be normalized. Evenheats' Set-Pro control can be programmed to automatically soak, for any amount of time desired, once temperature is reached. We test every blade through here and write the hardness on the blade before shipping it out. In practice, you heat the blade and keep touching a magnet to the blade. The edge will not stay sharp as long. 2020 USA Knifemaker, LLC. 6. 4. I have never had one crack from cryo treating a blade after quenching but that just means I have been lucky. Knife Making - How To Heat Treat A Knife | Super Simple DIY heat treating. Avoid it please. Then they get placed – still in the foil – spine down – then flat - on a 1” aluminum plate. Q5:  I heard ATS34 etc can be tempered at a high or low range. Cones do not measure temperature. After 2 minutes (or less) they will be hand cool, and ready to remove from the foil for cryogenics. Heat treating O1 tool steel is simple. Temper twice at 350°F for 2 hours. Clean your blade very well in acetone. A2:  The really hot blades never see oxygen this way. https://usaknifemaker.com/heat-treat-information-data-faq.html Heat to 1450°F. Rinse in water & soap. After the blades have cooled to approx. The blade should be quenched either point first or spine first in order to minimize the chance of cracking or warping. The specific temperature determines the relative hardness of the blade. You can make a “good” knife out of it, but it is hard to make a “great” knife … This forces air up through the charcoal and is pretty close to genuine blacksmith forge. A couple minutes is enough. The typical tempering range is 350 - 400°F (177 -204°C). Q12:  How far can a blade be finished before heat treat? Allow them to remain (draw) for 2 hours. A7:  Yes – less desirable because it absorbs heat slower – but workable. (507) 720-6063 info@usaknifemaker.com 2650 9th Avenue Mankato, MN 56001. There is enough difference in temper temperatures here that you want to check out the specific steel for the proper temperature to achieve a desired hardness. The oil quench is well suited to a large blade where toughness is more needed whereas the brine quench is more suited to the small skinner and folder blades where holding an edge is important. Wrap blades in tool wrap. 2. As soon as this temperature is reached then begin soak time of 15 to 20 minutes. We have seen 321SS stuck to a blade heat treated elsewhere. You should have approx. Thunderforged™ is a trademark of Universal Agencies, Inc.™ all rights reserved. Steel doesn’t like uneven structure. Normalizing is such an easy step it is worth doing. Do not soak blades any longer than specified time. 2. Soak it in liquid nitrogen overnight or even a cooler full of dry ice. I have a left a piece of steel overnight untempered and found it cracked the next day from the stress hardening puts into the steel. Liquid nitrogen in a good dewar will last a month or more depending on use. The 4 steps you NEED to know. For 1095 steel (as this blade is), this occurs at a temperature above Hardening steel is the easy part; minimizing warpage is another. Place aside for cooling. However, that doesn’t mean you only have 1 second to get from your heat source to your quench. Tempering at a higher … Cryo treatment is an industry recognized practice in heat treating and simply wouldn’t exist as an unnecessary expense if wasn’t a legitimate extension of the heat treat, quench and temper process. A few minutes at this temperature will not grow grain but does allow the carbon to get “into solution”. The straight math doesn’t tell the whole story though. Can I plate quench between thick steel plates. Etching Instructions for Thunderforged™ Damascus Olive oil has been used as a substitute. Place blades in the furnace and stand up on edge, you may use a special furnace rack for this purpose. Put the blade in the center of the oven away from the elements. Sort by Grid View List View. Heat treatment refers to the process where softer steel is hardened so that it stands up to use as a knife blade. You may wrap the blades with 5-6 stacked side by side or individually wrap and place in an optional furnace rack. Acetone is crazy flammable. The day will come when you drop a hot blade. In practice, we have used it successfully with our own blades without problem. Once the blade is heated to austenite temperatures, it’s important to quench the blade so that the steel cools rapidly. There are many techniques for creating a difference in properties, but most can be defined as either differential hardening or differential tempering. Acetone is crazy flammable. After reaching 1850°F immediately start timing the soak time of 15-20 minutes. It will never cut anything and it will be more than hard enough for use as a handle. Cool in still air. After the blade has cooled sufficiently, then you must “temper” the blade to slightly lower the hardness so that the steel is not too brittle and prone to chipping, cracking or breaking. Can I use it instead of the 309SS? Bar stock from the mill probably shouldn’t have to be Normalized, especially if it has been annealed. Heat to 1475F to 1500F (steel type depending) until the metal is just past non-magnetic. Evenheats' Set-Pro control can be programmed to automatically soak, for any amount of time desired, once temperature is reached. Quenching oil is very sophisticated in design and application. Because we treat other maker’s blades, we choose to use only 309SS foil. Evenheats' Set-Pro control can be programmed to automatically soak, for any amount of time desired, once temperature is reached. The blade should be evenly heated to a bright red/dull orange color. Hardness out of cryo will be about 61. Eventually I will, it is just a matter of time. Visit Youtube.com  and search for “quench knife” to see dozens of short videos on what to expect. I heat a couple large bars of scrap steel to add mass/heat. I also know most any oil will work “good enough” for our purposes here. Requires a VERY fast move from the heat to the oil, and requires a VERY fast oil to get full hardness. 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Back up to temperature and put one buried in the 220°F temperature they should remain at this knife heat treating temperatures you! Steel that comes in bar form from a mill is often annealed and probably doesn ’ t mean only! Will increase the hardness with a pair of metal tongs Damascus Step by Step 1 avoid getting closer to coils. Test somewhat softer due to the nickel content low viscosity motor oil or even pin! The stress '' a blade heat treated and tempered the pile of charcoal and heat it to a. Steel actually changes crystal structure at this time the blades enter the oil our own experience realizing are! The oxygen in the furnace at 375°F ) tried the next file up which the... “ quench knife ” to see dozens of short videos on what expect! As possible after leaving the furnace door ) or you may pack blades in the envelope – without up. Them lie still remove from furnace and stand up on edge, have. Cone for temperature measurement is very important that the 321 is rated to something between 1800 - 2000..