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Mule Team

Spyderco MT Mule Team Project

Dear Spyderco Customer,

Welcome to the Mule Team Project by Spyderco. In the English language the term mule has multiple definitions: There's the obvious equine reference being the offspring of a male donkey and a female horse. It can be a coin minted from two dies by mistake and the auto industry refers to their test vehicles as a mules. Spyderco also calls knife models designed and built for testing and evaluation Mules. When a group of these are brought together they make a team of mules, thus the name of our new knife release: The Mule Team.

Knife and steel-devotees love trying out new blade steels. Spyderco leads the industry in offering, testing and manufacturing knives using new and exotic blade steels. Taking that idea a step up, why not offer a series (team) of blades using different, exotic and freshly unveiled steels? In doing this steel-obsessed knife knuts can try, test and use something normally not offered to the industry.

Spyderco's Mule Team is a single-piece fixed blade pattern. The blade is leaf-shaped with a sharpened and finished PlainEdge blade but with an unfinished handle providing some a do-it-yourself opportunity. The unfinished handle has a series of holes for attaching a custom handle or for wrapping in cord. All Mule Team Pieces are sold without handle scales or a carry sheath focusing the project on the blade steel and opening the door for the owner to create his/her own handle scale and carry options.

The Mule team project was created as a simple, inexpensive venue for "steel junkies" to have an opportunity to test different blade steels themselves. Each run will have different interesting steel. Each run will have the same pattern, a fixed blade with a full tang. Each run will have the same thickness, grind, edge and will be heat treated to the optimal hardness for that steel. No handle, scales or sheath are provided. This not only saves you funds, but gives you the opportunity to make (or have made) custom handles and sheaths.

Thanx much and our appreciation for your interest and patronage of Spyderco products.

Yours truly,
Sal Glesser
President Spyderco Knives & Accessories

MT01P - Mule Team 52100 - January 2008

52100 is a high carbon steel used primarily for ball bearings. It has a good amount of carbon (0.98 - 1.10) and very few other alloys. Ball bearing steels usually have to withstand a great deal of force in a very small area. Traditionally, ball bearing steels make good edge steels because an edge also has to withstand much force in a small area. 52100 serves that function well. Oil quenched and drawn to Rc 62, it is a difficult steel to heat treat. A very fine molecular structure permits very sharp edges, even at thin angles. Toughness is good, corrosion resistance isn't. It is not a stainless steel and will have to be cared for.

MT02P - Mule Team CPM-M4™ - October 2008

Our second Mule in the series is a blade steel of CPM-M4. CPM-M4 is a high-speed, wear resistant, tool steel. It is non-stainless steel. Its high content of Molybdenum and Tungsten gives it a fine grain size, greater strength, hardness and toughness. It is a triple temper heat treat to make it as tough as possible without brittleness. The grinding combined with the triple temper heat treating process can cause warping up to 50 thousandths (.050) of an inch which is not enough to affect the performance of the knife. CPM-M4 will provide high edge retention and impact resistance with an Rc of 58-63; you'll also find it's relatively easy to sharpen.

MT03P - Mule Team CPMS90V™ - February 2009

CPM-S90V is not a new steel, but it is one not commonly used in the knife industry. It is a high carbon stainless steel formerly known as CPM-420V. With 2.3% carbon it offers wicked edge retention and higher tensile strength. It has more than twice the Vanadium than CPM-S30V, providing greater wear resistance. CPM-S90V may be uncommon in our industry due to its strength, hardness and toughness; all things that can prove to be difficult in a production atmosphere. Given the extreme wear resistance, it proved to be difficult to grind, the steel didn't want to "give" or "let go" of molecules. Although frustrating in production, this characteristic speaks to what can be expected in edge retention.

MT04P - Mule Team ZDP-189 - July 2009

Your Mule is made from ZDP-189. ZDP-189 blade steel is the hottest, hardest and highest performing Japanese knife steel in the knife industry today. 3% of its component ingredient is pure carbon and 20% chrome (unheard of chemistries twenty-years ago, making the steel harder and in turn extending its edge retention. This is done through a powdered metallurgic process. At press, Spyderco was one of a handful of cutlers around the world working with ZDP-189 blades.

MT05P - Mule Team 9Cr18Mo - October 2009

9Cr18Mo is a premium ingot high-carbon steel. In our experience it's the best knife steel being produced in China today. The name is derived from its component elements: .9% carbon, 18% Chromium and 1% molybdenum. With controlled heat treat and tempering it reaches a Rc of 58-62. Before its entrée into the knife industry it was widely used for high-end Chinese barbering scissors, roller bearings and surgical tools due to its corrosion resistance and high processing quality. The application of 9Cr18Mo to knife manufacturing opens up another steel option for high-end knife manufacturers and their high-end knife enthusiasts alike. The addition of a 9Cr18Mo Spyderco Mule fleshes out the series further by offering users the opportunity to evaluate and test drive a high-performance steel from yet another country.

MT06P - Mule Team CPM-S35VN™ - January 2010

Crucible Steel in NY created CPM-S30V as steel developed specifically to be used for knife blades. A first and the knife industry appreciates such purpose built efforts. Shortly after the introduction of CPM-S30V, Chris Reeve (of Chris Reeve Knives) began working with Dick Barber, a metallurgist at Crucible Steel (at the time). The goal was to create an even better version of the steel that had better machinability and finish. After several years of testing and development, the result was CPM-S35VN. Chemically the same as S30V, but with the addition of Niobium (also referred to as Columbium).

High Chromium ferritic steels containing Niobium exhibit increased temperature stability and refined grain structure which is important when working hard steels used in items like jet and rocket engines, welding and knife blades. It increases a blade's strength and ability to take and retain sharpness. Crucible worked with a few makers to test and refine the steel. Production began on CPM-S35VN just before changes were made in the Crucible business model.

At this time, there is still question as to whether this fine steel will be in production. Spyderco was fortunate to be able to grab some while it was still available and this Mule Team model is the result of that opportunity. CPM-S35VN is exotic in its chemistry, even for powdered steels. This is an opportunity for some to be able to play with this new evolution to blade steel.

MT07P - Mule Team Damascus VG-10 - October 2010

Spyderco's Damascus Mule Team is a laminated fifteen-layer steel with a Suminagashi pattern. The Damascus Mule's steel is composed of layers of erosive and non-erosive material over a VG-10 core center. The erosive layers are hard martensite stainless steel and the non-erosive layers are anti-corrosion nonferrous metal. These layers block carbon particles in the core from spreading to the outer layers. After layering the blade is forged to intentionally distort the layer-lines making a complicated, artistically beautiful pattern called Suminagashi. Suminagashi is the traditional Japanese art form of creating ripples of Chinese ink on the surface of water. This steel mimics the art form with interesting results on a knife blade. Once the layers are distorted, the blade is bathed in acid etching the pattern to vivid relief.

MT08P - Mule Team Aogami Super Blue - December 2010

Aogami Super Blue steel is produced exclusively by Hitachi Metals for tools and knives. In Hitachi's plant in the Shimane Prefecture, Japan, they use high quality iron-sand found only in this region. Shimane Prefecture sand has been used and preferred for making Japanese cutlery since ancient times. Hitachi creates and offers different grades of steels including white steels and blue steels. The steel isn't blue or white but the designation refers to the color of the paper the raw steel is wrapped in when delivered to Hitachi. It is common practice for Japanese steels to be named and referred to; based on what colored packaging the raw steel arrives to the maker. Super Blue is the highest grade blue steel and contains up to 1-1/2% carbon for wear resistance and chrome to elevate hardness and improve edge holding and corrosion resistance. Steel smiths agree Super Blue is easier to heat-treat and work with than some steels but is more wear resistant and harder to hand grind. Classified as exotic steel by cutlery standards, it has a loyal following with custom kitchen knifemakers looking for superior cutting performance for cutting materials that are soft and sticky to rock hard or fibrous.

Steel Carbon Chromium Manganese
Hitachi Aogami Super Blue 1.40-1.50 0.30-0.50 0.20-0.30

Molybdenum Phosphorus Silicon Tungsten Vanadium
0.30-0.50 0.03 0.10-0.20 2.00-2.50 0.50

MT09- Mule Team Cobalt Special - February 2011

Takefu is a premier Japanese steel company specializing in the production of steels used for household and industrial cutlery. They produce blades using clad steel. Clad steels are a composite of different metals some hard, some softer, fused or bonded to each other. Paring different steel types together elevates performance by combining the best characteristics of each material and where the steels overlay each other, a fine line develops. Traditional Japanese swords featured clad steels, layering tough harder steel with softer bendable ones which resulted in a steel combination that made them difficult to break or bend. Spyderco's MT09 Mule Team is Takefu's Cobalt Special steel enveloped within slices of SUS420J2. The two steels laminated as one boost toughness, improve corrosion resistance and generate lasting sharpness in a blade that is relatively easy to sharpen.

Steel Carbon Chromium Cobalt Manganese Molybdenum
Cobalt Special 0.95-1.15 15.00-17.00 2.00-3.00 0.30-0.50 1.00-2.00

Nickel Phosphorus Silicon Sulfur Tungsten Vanadium
0.25 0.03 0.60-0.70 0.01 0.20-0.30 0.20-0.30

MT10P - Mule Team CTS-BD1 - June 2010

High-performance American-made blade steels are propelling the quality and performance of today's knives to new and higher levels. A U.S.A company called Carpenter Steel recently entered the knife making arena, cutlery people noticed. Carpenter isn't a newcomer to alloy manufacturing just a new-neighbor in the community of blade steel manufacturing and they're launching a new family of alloys called CTS™ steels specifically for cutlery. One of those is CTS-BD1. CTS-BD1 is patterned on Gingami I (also known as G2), the gold-standard for Japanese cutlerers. Its superior edge retention and surface finish are machined to a fine edge and it heat-treats consistently. From a performance standpoint, it's a winner and it's used in Spyderco's latest Mule Team fixed blade.

MT11P- M390 Mule Team - June 2011

The Austrian's Böhler Group merged with Sweden's Uddeholm Steel Works in 1991, creating the world's largest tool steel manufacturer, Böhler Uddeholm. Specializing in aviation/aerospace and automotive steels, they also produce tool steels used in the manufacture of consumer goods including electronics and cutlery. Through a powdered metallurgy processes they produce M390 Microclean steel which is highly sought and well suited to today's high-performance cutlery. M390 is a martensetic chromium steel highly resistant to corrosion. The powdered granules of Chromium and Vanadium in the steel are small, consistently sized, and finely dispersed in the steel's matrix (mix) making it exceptionally homogenous. This means for the consumer cutting with M390 will experience a high-level wear and corrosion resistance and the blade steel can be polished to a mirror-like finish.

Steel Carbon Chromium Manganese Molybdenum
Böhler Uddeholm M390 1.90 20.00 0.30 1.00

Phosphorus Silicon Tungsten Vanadium
- 0.70 0.60 4.00

MT12P- Cru-Wear Mule Team - September 2011

Spyderco's twelfth Mule Team Project installment features American-made steel called Cru-Wear. Upstate New York's Crucible Steel manufacturers Cru-Wear which is very similar to Vascowear, a steel used by Gerber Legendary Blades in many of their past production knives.

Cru-Wear is a high-performance "V" tool steel that is difficult to process making it challenging for knife manufacturer to work with. It follows the same high-alloy, metallurgical tool-steel recipe used to produce D2, but with greater levels of vanadium, tungsten and molybdenum. It is air-hardened and worked in a cold state. Cru-Wear exhibits exceptional toughness, impact resistance and hardness for exceptional edge retention and is the first tool steel offering in Spyderco's Mule Team Series.

MT13P- Elmax Mule Team - February 2012

Spyderco’s thirteenth Mule Team Project installment uses Elmax steel produced by Böhler-Uddeholm Steel of Kapfenberg, Austria.

Böhler first sold steel in North America in 1925 by providing European-made steels to toolmakers, manufacturing industries and construction jobs in the U.S.  Their Elmax is an alloy composed using powdered metallurgic technology that was designed specifically for high-tech applications, primarily for use in the electronics industry.  It contains elevated levels of chromium, vanadium-molybdenum that deem it a well-tailored fit for making knife blades.  These elements translate into resistance to wear and corrosion and it has a homogenous grain structure making it malleable when grinding and forming.