To create by our craftsmanship skills

「Hand Scraping」

To handle hand scraping technique , long years experience is required. Hand scraping craftsman has decreased in current years in Japan. SAKURAI continuously uses this traditional technique to keep manufacturing high precision machines with less secular change.

The purpose of hand scraping

Hand scraping is the only method for producing an original set of flat surfaces from which one can transfer that accuracy and flatness through to other surfaces by means of grinding and such accuracy and flatness can not be achieved by machine lapping or grinding. With two perfectly flat surfaces, lubrication is pressed out leading to mating components that are prone to sticking. With hand scraping, mating surfaces smoothly glide against each other, rather than stick, that leads to incredibly smooth sliding.

The main hand scraping sites■Rotary milling machine : bed, sliding column, arm
■Other machines : feed unit, sliding column, mounting parts of spindles
What is hand scraping

Traditional hand scraping is a meticulously manual technique where a highly skilled and experienced craftsman uses their body weight against a carbide hand scarper to remove very small amounts of metal and create thousands of textured patterned divots along finishing slide guide mating components.With hand scraping, mating surfaces smoothly glide against each other and ideally, flatness consists of twenty five contact points per square inch, aligning components within 0.0001 of an inch – reinforcing stability, providing better balance, and giving the machine tighter alignments and tolerances.

Spindle motor assembly technology

With the development of spindle motor technology, high speed RPM’s are is in great demand. Not only is the high standard of rotating parts such as the spindle and bearing expected, but also durability of related parts and housing are required. For achieving high speed and accuracy, the shaft and spindle become the most essential parts for spindle motor. Vibration of the spindle increases as motor speed increases. To deal with the vibration caused by increasing speed, a Fast Fourier Transform (FFT) based monitoring system is applied to monitor, measure, and analyze the vibrations of the high-speed spindle so that vibrations can be finally eliminated. Spindle motors are carefully assembled one by one by skillful and experienced craftsmen with years of assembling experience required for such assembly.

To create by 3D technology

To achieve high efficiency, high quality, and time reduction, SAKURAI uses 3D data for process designing, structure analyzing and machine manufacturing. By using the latest designing software and machining equipment, along with 70 years of accumulated knowledge, craftsmanship skills, and experience, SAKURAI continually provides high value added products.

3D design・Structure analysis


SAKURAI utilizes 3D AutoCAD as the main tool for designing and developing machinery and machine tools. Utilizing 3D models and illustrations, detailed information can be efficiently discussed and exchanged between our customers and Sakurai staff. This close relationship with our customers contributes to improved quality of service and products, including reduced design and manufacturing time. Additionally, using 3D AutoCAD for analyzing machine structure and facial pressure strength at early the stages of design makes prototypes comparatively speedy as well as avoiding potential end result disasters, therefore, time and cost are also reduced.


By using CAM software, NC program date can be extracted directly from AutoCAD designs and conveniently transferred to the manufacturing equipment to aid in manufacturing accuracy and efficiency. CAM data can also be easily adapted to both 2D and 3D data.

By using CAM■Siemens「Solid Edge」「NX」

Investigating virtual specification by using VR

SAKURAI uses VR(Virtual Reality) for its prior inspection. A head-mounted display (HMD) more fully immerses the user in a 3D virtual world. It helps investigating tiny interference problem and engineering access problem, which is hardly inspected by only 3D data. A 3D life-size model can be created and investigated before prototyping or manufacturing.