ROCKSTEAD knives - developed and manufactured in Japan - stand for the highest standards of functionality, practicality and aesthetics. They combine innovation and tradition in an incomparable way. Their unsurpassed sharpness, their outstanding edge retention and their unique design are the result of the combination of the most modern manufacturing technologies with the traditional knowledge in the art of making knives and swords. Despite the use of specially developed high-tech processes, numerous steps during the finishing process can only be carried out by hand. The effort involved is enormous and the quantities are consequently small. In the development of new models and the further development of existing ones, ROCKSTEAD takes into account the wishes of ROCKSTEAD customers all over the world and uses the term "factory custom knives" for knives manufactured in this way. A ROCKSTEAD knife represents what is technically feasible in the manufacture of a knife. Each individual ROCKSTEAD knife sets new standards in terms of cutting performance, is uncompromising in the use of materials and unique in its aesthetic and functional design.
The company "ROCKSTEAD Corporation" is located in Sakai, a part of Osaka Prefecture in Japan. ROCKSTEAD has set itself the goal of producing knives that are equal to or even superior in quality to handmade knives. For more information, please visit the manufacturer's website: www.rockstead.jp.
ROCKSTEAD - Cutting performance
The quality of a knife is primarily defined by its cutting performance. Optimising this was and is the most important goal that ROCKSTEAD pursues in the development and production of knives.
When ROCKSTEAD began producing knives, the following goals were defined: 1. ROCKSTEAD knives should cut exceptionally well!!! 2. only the most suitable steels should be used (in cooperation with Hitachi, the premium blade steel ZDP-189 was developed for this purpose). 3) ROCKSTEAD knives should have a perfect mirror surface to prevent chipping. 4. the blade geometries should allow for optimal power transmission as well as exceptional sharpness and edge retention.
From the very beginning, ROCKSTEAD has used two steels, ZDP-189 and YXR-7, the latter of which meets the requirements for toughness in particular and is coated due to its lower corrosion resistance compared to ZDP-189. The exceptional cutting performance of ROCKSTEAD knives has since been impressively demonstrated at blade shows worldwide.
In our video, Noriyuki Ishida demonstrates the use of ROCKSTEAD's two preferred steels (ZDP-189 and YXR-7). Note the simple but very effective maintenance method: metal polish is applied to a board covered with denim, allowing the blade to be gently stripped after prolonged or intensive use. The sharpness of a ROCKSTEAD knife can be maintained in this way for many years without "re-sharpening".
To the video:
作 zukuri Youtube video "ROCKSTEAD cutting performance".
An impressive test of cutting performance was conducted and recorded by ROCKSTEAD in 2005. Hiroshi Hanada cut a 25mm hemp rope with the SHIN-ZDP almost 800 times without any chipping of the blade.
ROCKSTEAD Knife Sharpening
Sharpen like the manufacturer! With the Z.2.1
The zukuri Z.2.1 is a sharpening system that can be used to resharpen all common knives. It was designed to enable the sharpening of convex blade shapes. The practical and extremely solid construction is modelled on a tool from the ROCKSTEAD Corporation and produced in cooperation with Schwarz Metallbau GmbH in Germany.
As a further development of the Z.2, the Z.2.1 has an improved tensioning device that makes threading and tensioning the sandpaper much easier.
How to use the Z.2.1
You can see how to use the Z.2.1 in this YouTube video:
YouTube Video zukuri Z.2
ROCKSTEAD - materials used
Blade steels For the "heart" of the knives, the blade, ROCKSTEAD uses two of the best blade steels currently available: ZDP-189, the powder metallurgical steel specially developed by Hitachi for knife blades, and YXR-7, the "High Speed Steel" known for its special toughness. Decades of experience in the production of cutting tools have enabled ROCKSTEAD to develop manufacturing processes that guarantee the best properties for knife blades with these steels.
Premium blade steel ZDP-189 is a powder metallurgy steel developed by Hitachi Metals specifically for cutting tools, especially knife blades. It has a particularly fine and uniform microstructure and is characterised above all by its exceptional wear resistance and excellent corrosion properties. In order to realise the best properties of this material in a knife blade, a very precise heat treatment is required. ROCKSTEAD achieves a hardness of up to 67 HRc when processing this steel. However, ZDP-189 only develops its full cutting performance when suitable blade geometries are used (HONZUKURI and SHINOGIZUKURI), as used by ROCKSTEAD. Knives with a blade made of ZDP-189 retain their sharpness for an above-average period of time. Due to its lower toughness compared to the blade steel YXR-7 (see below), use for "percussive" cuts is not recommended. Composition: The exact composition is not known. Therefore, only the most important elements can be listed here: Carbon: 3%, Chromium: 20%, Molybdenum: 1.30%, Tungsten: 1.50%, Vanadium: 0.10%.
Composite blades (laminated steel)
In order to give more stability, especially to the larger blades made of ZDP-189 blade steel, some of the premium ROCKSTEAD models are manufactured with a "composite blade" (laminate steel). For the outer layers, VG-10 stainless steel is currently used, which many manufacturers use for their knives due to its good wear resistance (possible hardness up to 62 HRc) and rust inertia. In earlier models, ATS-34 steel was used instead of VG-10 steel. If you look very closely at such a blade, you will see a fine line above the cutting edge reminiscent of the hamon (hardness line of Japanese blades). In our ROCKSTEAD shop these blades are marked "ZDP-189 clad by VG-10" or "ZDP-189 clad by ATS-34".
The YXR-7 blade steel is a high-speed steel (HSS steel), which is also manufactured by Hitachi Metals. The steels of the YXR series are high-strength and particularly tough. They are mainly used as punches and dies in hot, warm and cold forming and also as trimming dies. They have already received several awards for their performance as mould and tool steels. Due to the lower carbide increases, the YXR-7 steel has outstanding toughness despite its enormous hardness (around 65 HRc). However, compared to the blade steel ZDP-189, it has less favourable corrosion properties, so ROCKSTEAD coats this blade steel. The coating is applied to the entire blade surface. The coating is only removed again from the cutting phase. It is therefore recommended to wipe the knife dry after use to prevent corrosion. Knives with this blade steel are extremely robust and are particularly suitable for heavy work and "percussive" cuts. Composition: The exact composition is not known. Therefore, only the most important elements can be listed here: Carbon: 0.8%, Chromium: 5%, Molybdenum: 5%, Tungsten: 1.10%, Vanadium: 1.10%.
As the blade steel YXR-7 is less rust resistant compared to the blade steel ZDP-189, the blades of all ROCKSTEAD knives made from this steel are coated. Most commonly, ROCKSTEAD uses the DLC (Diamond Like Carbon) coating with a hardness of up to HV1800. For some years now, blades have also been provided with a titanium coating (TIN or HPC). This is much harder and therefore more wear-resistant than DLC. It reaches a hardness of up to HV3000 and has an even lower coefficient of friction. Visually, these two coatings can be distinguished by their colouring. DLC is very dark, almost black. Titanium coatings, on the other hand, are usually lighter and shimmer bluish or violet.
On some models, the grip plates are given a special DLC coating: "DLC Prism". Compared to the conventional DLC coating, this coating is thinner and harder.
ROCKSTEAD knives are completed by the use of the best materials that are optimally suited to their purpose. These include: Hardened aluminium, titanium and waterproof desert ironwood for handles and handle scales, selected pieces of the skin of pearl rays for inlays or as handle wrapping. The processing of all components is carried out within the smallest tolerances and at the highest, qualitative level. Aluminium (Duraluminium) ROCKSTEAD uses two aluminium alloys. Duraluminium, also known as A2024, is an aluminium alloy that stands out, especially in comparison with pure aluminium, due to the high strength and hardness achieved as well as its particularly high corrosion resistance. The alloy A6063 also has a higher hardness and strength than pure aluminium and also has a very good surface quality. The ROCKSTEAD models HIGO, HIZEN, TEI, SHIN, KOU and CHI have handles made of these materials.
Titanium is much lighter than steel, yet has remarkably high strength and is corrosion resistant. Although not easy to work with, these properties make titanium a material that is used in a variety of ways. At ROCKSTEAD, the Gentleman Knife SHU is currently being manufactured with titanium handle scales.
ROCKSTEAD uses this wood for handles, for example in the models HIGO-X or CHOU-IW. One of the first fixed knives, the JIN model, already had a handle made of this rare material. Ironwood is heavy, very dense and one of the most resistant woods of all. The remarkable patterns and high contrasts in its colouring also make it an unusual and popular material.
Micarta (Wood Micarta)
Micarta is a so-called fibre-plastic composite. In its production, various sheets or layers of an absorbent base material, such as wood, linen or cellulose, are impregnated with phenolic resin and then pressed together under high pressure to form a whole. After the resin has hardened, Micarta can be worked very well, e.g. sanded, whereby a grain emerges on differently coloured materials. Micarta feels very pleasant, very natural and is waterproof. Another advantage is that Micarta can be dyed almost any colour. It is no coincidence that Micarta is one of the most commonly used handle materials. ROCKSTEAD uses this practical, durable and visually appealing material for the models KON-ZDP (brown) and KON-DLC (black).
Stingray leather is rare and difficult to cut, usually only with special tools. The hardness of the pearls is reminiscent of glass pearls. Stingray is traditionally used in Japan for inlays or as handle wrapping. It has an anti-slip effect and is extremely durable. ROCKSTEAD only uses selected pieces, which must visually match the respective knife. For the processing, ROCKSTEAD has developed special procedures that make it possible to produce extremely precise and accurately fitting inlays. This ensures that the inserts continue to fulfil their function even after years of use. Pearl ray is currently used for the TEI, SHIN, KOU and CHI folder models as well as for the GI and UN handles. The handle of a GI or a UN is completely equivalent to that of a katana. This applies not only to the use of stingray leather, but also to the design of the entire handle winding. These handles are made in the traditional way especially for these knives in a specialised workshop.
In addition to the heat treatment optimised for these steels, it is the blade geometries used (HONZUKURI and SHINOGIZUKURI) as well as the mirror polishing over the entire blade surface that form the basis for the unique characteristics of a ROCKSTEAD knife.
This double-sided convex blade surface - HONZUKURI - is based on the blade shapes of Japanese katanas. It guarantees maximum cutting performance and ensures edge retention for many years. The production of these blades, which are also aesthetically perfect, is particularly time-consuming and cost-intensive.
In the second blade shape used by ROCKSTEAD - SHINOGIZUKURI - the surface is not convex, but runs in planes with angles of 30 and 24 degrees. These degrees are the result of ROCKSTEAD's in-depth research into optimal power transmission. This shape also promises exceptional cutting performance and long-lasting sharpness.
The perfect mirror polish typical of all ROCKSTEAD blades is far more than just a sophisticated finish. It reduces chipping and significantly improves the edge retention of the knife. As much as this perfect mirror polish is owed to a practical benefit, it is also an expression of a unique aesthetic that ultimately also reflects ROCKSTEAD's perfectionism in the manufacture of each knife. This mirror polish is a special quality feature and can only be found in this perfection at ROCKSTEAD.
Last but not least...
...YOUR ROCKSTEAD also needs regular maintenance and care. This is particularly easy with the HIGO models, which are supplied with a matching spanner for loosening just two screws. It was designed to be simple so that it can be cleaned quickly and easily, even if it is very dirty. However, a drop of oil (for example WD-40) does all ROCKSTEADS good from time to time. Knives with YXR-7 blades should always be wiped dry after use to prevent corrosion. The most important measure, however, is to pull off the blade after heavy use. In this way, the smallest damage to the cutting edge, which inevitably occurs during use, can be eliminated before larger chipping occurs. In our experience, the most suitable and very simple method is described by the manufacturer ROCKSTEAD on its homepage under the keyword "maintenance". If re-sharpening has become necessary over time, you can make use of ROCKSTEAD's lifetime free sharpening service. You only have to pay the shipping costs.
In the event of major damage to the blade or other defects, ROCKSTEAD will provide you with a cost estimate and will only carry out a repair if you expressly request this. Otherwise, your knife will "merely" be returned to you sharpened. With correct, proper handling and care, you will be able to maintain the above-average sharpness of your ROCKSTEAD knife for many years without having to have it resharpened.
You want to resharpen your ROCKSTEAD knife yourself?
This is possible with the "zukuri Z.2.1" sharpening system.
The zukuri Z.2.1 is a sharpening system with which all common knives can be resharpened. It was designed to enable the sharpening of convex blade shapes.
Using the Z.2.1
You can see how to sharpen with the zukuri Z.2.1 in this video:
YouTube video zukuri Z.2