Paragon KM-24D Knife Maker’s Heat Treating Furnace
Wherever humans have withstood severe tests—whether in the steaming jungles of the South Pacific, the burning desert of Africa, or the cold, blowing wastelands of Korea—they have depended upon great knives. Wherever explorers have gone, they have taken great knives with them—over the prairies and mountains of the American west, across the desolate plains of the North Pole, through the silence of deep space.
Not all great knives face extreme tests. Some are carried into combat and rarely used. Others see no more action than a camping trip. Yet each bears the imprint of its maker. Each contains a spirit that makes it feel alive to the touch. Each extends a secure feeling that comes from wearing a knife you can depend on. The maker, immersed in the dust and sweat of his work, sends a part of himself with each knife that leaves his shop. He lives on in his knives.
Test exotic heat treating formulas
When you own a Paragon KM-24D furnace, our most popular size, you can live the knife making adventure to the fullest. You will actually witness the birth of your knives in the bright red heat of the furnace. And all Paragon furnaces are now rated to 2350F, so you can fire as hot as you need to. Click here for links to all the Paragon knifemaking furnaces.
Many knifemakers enjoy owning a furnace, because for one thing, they can revel in testing. After each test, they tweak the heat treating to squeeze the best performance from the steel. They test for Rockwell hardness, but they don’t stop there. The serious knifemaker tests the knife against hemp rope and even 2x4s. How many times will it cut before dulling? They bend the blade to 45° or even 90°. Then they straighten the blade, slap on a handle and test it in the real world.
With a KM-series furnace, the knifemaker can try exotic heat treating methods at his leisure. Does quenching in dry ice really improve blade performance? What happens when 52100 steel is triple-quenched with a one-day wait between each quench? After this treatment, will a 52100 blade bend to 90° without chipping?
With a Paragon furnace in your shop, all questions about heat treating formulas are settled. It is no longer only theory. You find out for yourself what works. Testing and heat treating is at the heart of the knife making adventure. Here is where your confidence as a knife maker takes root.
Experiment with differential hardening, an ancient bladesmith technique. Try out the newest tool steels. Are they really as good as the tried and true D2 and A2? Do they hold an edge yet remain easy to sharpen?
New higher furnace temperatures
Paragon’s knifemaking furnaces are now rated to 2350 degrees F, so you can heat treat as hot as you need to. Try out the newest tool steels.
A message from Ed Fowler, Master Blade Smith, (Member, American Bladesmith Society)
“Paragon offered me no financial rewards or free equipment for this endorsement. I recommend Paragon furnaces only because they make an excellent, reliable product.
“I've made knives off and on since the sixth grade. I enjoy every second in the shop making knives. I used to harden and temper with a torch. As my skills increased, my testing of knives revealed the benefit of longer and more uniform soak times during the annealing and tempering cycles than were possible with a torch.
“I finally bought a Paragon furnace. It is extremely beneficial to bladesmithing, because it allows us to do things with our blades we couldn't do otherwise. If I had known how good they are, I would have bought one years before I did.
“You don't want to introduce any variables into your blades by accident, and temperature is one such variable. With a Paragon, you know exactly what causes what and why. My advice to beginning knifemakers is to use the best equipment you can as soon as you can add it to your shop. I wasted a lot of time and energy trying to make knives with less than the best equipment for the job. Invest in quality equipment, learn how to use it right, and use your time seeking the best knife you can make.
“Without my Paragon oven, I would have never made the discoveries about steel that I’ve made. I love my Paragon. That Paragon sure made a big difference in my knife making. Any experiment I want to run is right there. If I want to change a heat treatment, I know exactly how. With every knife, I learn more.
“Thermal cycles, commonly known as heat treating of blades, are the most significant single aspect contributing to the quality of a knifemaker’s blade. Knifemakers who wish to explore the absolute frontiers of the world of knives in search of the Excalibur of their dreams must have the ability to design thermal treatments specifically intended to push their steel to the highest limits of performance. Absolute control of the temperature of their blades is absolutely essential to success.
“Paragon makes a nice piece of equipment. I recommend it very highly to anyone who asks and to many people who don't ask. In order to make knives that my customers can depend upon, I have to be able to count on my equipment to provide consistent performance. My Paragon heat treating oven has always provided the degree of dependability I can count on to support my commitment to provide my customers the best functional knife possible.
“Believe me, I'm much richer knowing I'm making the best knife I can. I'm much happier with myself.”
A bond of trust between you and the knife owner
We understand the knife maker, because we live by the same credo, which is simply to create a knife, or a furnace, that represents the maker himself. Quality of work is not just a fad for a knife maker. It is a passion. Anything less than one’s best is unthinkable.
The buyer of a custom knife appreciates fine detail. He or she marvels at the lines and curves and the mirror-like finish the maker coaxed from the steel with such patience. There is a bond of trust between the owner of a fine knife and its maker. This is why the knife maker sleeps better when he controls every step in creating a knife.
The knife maker derives joy from working with his hands. He makes knives that are not merely prized, but treasured. When the knife owner wipes a rag across such a knife, he is caressing as much as cleaning it. Part of this spirit of knife making is lost when you send the blade out for heat treating and await its return.
Every time you, the maker, release one of your knives to the world, your reputation goes with it. This is why makers feel compelled to control every step in the blade’s journey from initial design through final polishing.
No more waiting for commercial heat treating
A Paragon KM-series furnace sets the knife maker free. No more wrapping blades and mailing them to your heat treater. No more waiting until you have a dozen blades to get the best price on heat treating. No more turning away orders for last-minute gifts.
While your furnace is hardening and tempering blades, you can busy yourself grinding more knives or fitting handles. After you’ve used your Paragon furnace awhile, you will wonder how you ever got along without it.
When asked to make a knife on short notice—whether for a Marine Corps awards presentation, a soldier’s pre-deployment party, or an archaeologist on his way to Africa—you will be ready. When a custom knife is needed as a going away gift, and the recipient is leaving in three days, you will be ready. Your KM-series furnace might even pay for itself on rush orders you would otherwise have missed.
Own a furnace and you alone decide when you will complete a knife. If you stay up one Friday grinding a knife, you can heat treat it that evening and deliver it Saturday morning. Just in time for a grateful wife to present to her husband on his birthday.
Finishing a knife whenever you want will excite you. You will find yourself working into the night to complete a new design. When you send the blade out for heat treating, the excitement of making it is forgotten. By the time the blade returns, you hardly remember it.
A full range of Paragon furnace sizes
The KM-series knifemaking furnaces come in five interior sizes:
- KM-14D and Xpress-KM-14: 14 ½” long, 5 ½” wide, and 4 ¼” high
- KM-18D and Xpress-KM-18: 18” long, 5 ½” wide, and 4 ¼” high
- KM-24D and Xpress-KM-24: 24” long, 5 ½” wide, and 4 ¼” high
- KM-36D and Xpress-KM-36: 36” long, 5 ½” wide, and 4 ¼” high
- KM-45D: 45” long, 5 ½” wide, and 4 ¼” high
Even if most of your knives would fit inside the KM-14D, you may ultimately be happier with the KM-24D, the most popular size. Too much capacity may be better than too little. After all, it doesn’t hurt to heat shorter blades in the longer KM-24D; electrical consumption is minimal. Our newest KM-18D is mid-way in length between the KM-14D and KM-24D so you can buy just the right size for your needs.
Your choice of two temperature controllers
The Sentry 12-key controller is faster to program and has more features than the Sentry Xpress 3-key controller. However, the Sentry Xpress is more economically priced. Now you can choose the controller that fits your budget.
Models with the 3-key Sentry Xpress controller: Xpress-KM-14, Xpress-KM-18, Xpress-KM-24, Xpress-KM-36.
Models with the 12-key Sentry controller: KM-14D, KM-18D, KM-24D, KM-36D, KM-45D.
Solid furnace construction
The door opens downward with one-handed operation. A counter-weight handle holds the door securely closed. The furnace is insulated with long-lasting refractory firebrick. The elements are mounted in dropped, recessed grooves machined into the firebrick. Paragon invented this type of groove in 1952. This groove protects the element for long life and low maintenance. Elements are simple to replace because they’re exposed rather than embedded. You can thread new elements into place following clear instructions in the manual.
The temperature sensor (thermocouple) is sheathed for long life. The thermocouple-to-controller wire is kept inside the control box for protection from the harsh environment of the typical bladesmith shop.
The firing chamber is protected by a rigid steel case painted in high temperature blue. A built-in stand lifts the firing chamber safely off your worktable, so no extra stand is needed. The door is mounted on a heavy-duty hinge shaft for smooth opening. Because of the rigid case and heavy hinge, the door is sturdy enough for years of faithful service. A chain holds the door open and out of the way so you can remove hot blades without bumping into a swinging door.
A micro safety switch shuts off the power to the elements when the door is opened, yet the temperature controller remains powered. The safety switch is standard on Paragon KM furnaces. This is just one more extra feature that you will appreciate for years to come.
We use high temperature wire in the switch box for long life. A heat shield, mounted between the switch box and furnace, helps keep the switch box components cool even during extended operation. To further dissipate heat, the switch box is extra large and generously slotted. Each furnace comes with a cord and plug for immediate installation, and a one year warranty.
Detailed heat treating instructions
Your furnace includes a wiring diagram, programming instructions, and heat treating manual. The manual gives you basic heat treating instructions for D2, 440C, ATS 34 and 154 CM. The manual is written in plain English for the beginner. Once you have mastered the basic heat treating formulas, you can tweak them to your heart’s content.
Made in America
45% of Paragon’s factory work force has been here over 10 years; 20% have worked here over 20 years. All Paragon furnaces are made in Mesquite, Texas. We are proud to support the American worker.
Optional Gas Injection Flow Meter
During heat treating, scale forms on the surface of the steel. One way to eliminate most scaling is to wrap the steel in stainless steel foil. Another way is to install the gas injection flow meter on your furnace. It is available as either an add-on kit, or you can order the furnace with the meter installed.
The meter regulates the flow of an inert gas, such as argon, inside the furnace. The gas displaces the oxygen to prevent most scaling.
Please remember that results with the flow meter vary depending on the type of inert gas you use and your level of experience. For more details, click on the link in the Options section below. Also please understand that the inert gas will not remove all of the scaling.
The knifemaking Kit
In addition to the furnace, you will need a Knifemaking Kit, which separates the blades and holds them parallel inside the furnace. Please click the link below in the Options section.