Observation of fracture surfaces and understanding of the safety zone in fatigue testing of metallic materials.

[Reproduction of Private Spring Preparatory School Lecture 17] Metals also change when they are fatigued! An explanation of how the results of fatigue tests are organized and utilized in design.

last updated Oct 30, 2026

A detailed explanation of the material fatigue strength testing process and the creation of S-N curves.

[Reprint Private Spring Preparatory School Lecture 16] What is a fatigue test? An explanation of its purposes and how it is conducted.

last updated Oct 30, 2026

Discussion and Analysis on the Progress of Fatigue Destruction and the Geometric Characteristics of Destruction Surfaces

[Reproduction of Private Spring Preparatory School Lecture 15] Explanation of ductile fracture and brittle fracture! Also explains the smooth and rough surfaces of fatigue fracture.

last updated Oct 30, 2026

The influence of dynamic stress and fatigue failure in automobile springs and its relationship with road conditions.

[Reproduction of Private Spring Preparatory School Lecture 14] Characteristics of stress on springs! Used under significantly larger static and dynamic stresses.

last updated Oct 30, 2026

Experimental study on wire repeated bending tests and fatigue limits, and their industrial applications.

[Reproduction of Private Spring Preparatory School Lecture 13] Explanation of the repeated bending test! It also explains the differences from the repeated bending fatigue test.

last updated Oct 30, 2026

The relationship and challenges between the development of the Japanese spring industry and the automotive industry.

[Reproduction Private Spring Preparatory School Lecture 12] The hardness of each railway plate spring is measured! Brinell hardness testing machines are installed simultaneously in all factories.

last updated Oct 30, 2026

The evolution of spring technology and heat treatment methods during the Showa period and their historical background.

[Reissue Private Spring Preparatory School Lecture 11] Explanation of single and double quenching methods! Discussion of new materials and technologies as well.

last updated Oct 30, 2026

Establishment of Standards and Changes in Steel Materials in the Spring Industry during the Showa Period

[Reissue Private Spring Preparatory School Lecture 10] About the spring industry during the Showa period! Establishment of various standards and specifications, from JES to JIS.

last updated Oct 30, 2026

The development of the automobile and aircraft industries during the Showa period and the role of the spring industry.

[Reproduction of Private Spring Preparatory School Lecture 9] Explaining the transition of the automotive and aerospace industries! Also discusses war and the spring industry.

last updated Oct 30, 2026

The invention of the Katasa testing machine in the late Taisho period and the characteristics of Rockwell and Vickers.

[Reproduction of Private Spring Preparatory School Lecture 8] Explanation of two new hardness testing machines! Inventions of Rockwell and Vickers.

last updated Oct 30, 2026

The advancement of automobile development and spring technology, as well as innovations in materials and research progress in the late Taisho period.

[Reproduction of Private Spring Preparatory School Lecture 7] The Emergence of Automobile Springs, the Great Earthquake, and the Major Advancement of Automobiles! The late Taisho period was an era when spring research became full-fledged.

last updated Oct 30, 2026

The development of the spring industry in the early Taisho period and technological innovation through the introduction of testing machines.

[Reproduction of Private Spring Preparatory School Lecture 6] Standards and specifications for steel materials and springs have been established! The spring industry made great strides in the early Taisho period.

last updated Oct 30, 2026

The evolution from horse-drawn carriages to automobiles and the development and modernization history of Japanese spring manufacturing.

[Reproduction of Private Spring Preparatory School Lecture 5] The rickshaw is also a benefactor for the spring industry! It also discusses the modernization of the spring industry.

last updated Oct 30, 2026

The measurement principle and advantages of shore hardness testing machines, and the historical background of the development of the spring industry.

[Reproduction Private Spring Preparatory School Lecture 4] A different measurement method! Explanation of the Shore durometer applying the principle of rebound.

last updated Oct 30, 2026

Types of spring hardness testing machines, differentiation and precautions during measurement.

[Reproduction of Private Spring Preparatory School Lecture 3] Explanation of the Brinell hardness testing machine! Hard materials are tested with a red signal, and the testing surface is generally flat.

last updated Oct 30, 2026

Learn about methods for measuring hardness and the types, roles, and importance of testing machines.

[Reproduction Private Spring Preparatory School Lecture 2] The national standards for power test machines, testing methods, and reference pieces are firmly established in JIS!

last updated Oct 30, 2026

Methods for comparing the hardness of minerals and metals, and testing methods using diamonds.

[Reproduction of Private Spring Preparatory School Lecture 1] Comparing Hardness: It's About Scratching! An explanation of metal hardness and a testing machine using diamonds.

last updated Oct 30, 2026

[Data] Accurate Tangless Insert

Introducing a method to dramatically improve the efficiency of wire insert insertion work!

last updated Oct 30, 2026

Stock sales site for springs, fasteners, and special screws.

You can purchase products listed in the comprehensive catalog online.

last updated Oct 30, 2026

Ultra Spring Tension Coil Spring Series

Thorough quality control!

last updated Oct 30, 2026

Spring Battery Spring (Plate)

We also produce custom-made items!

last updated Oct 30, 2026

Spring battery spring

We also produce custom-made items!

last updated Oct 30, 2026

Spring, torsion spring

The spring constant of this specification is calculated with an arm length of 1/2 and a free angle B (135°), and the allowable displacement is based on the stress from static load.

last updated Oct 30, 2026

Constant load and constant torque spring

Even if the spring stroke is lengthened, the output remains unchanged, maintaining a constant output!

last updated Oct 30, 2026

Close-coil spring

Custom orders can also be accommodated!

last updated Oct 30, 2026

Toppla Screw (R)

The screw head won't get crushed! Perfect for preventing screw tightening failures!

last updated Oct 30, 2026

Bane's AKIBA Showroom

We welcome consultations from those using springs for the first time, as well as those who are currently facing difficulties! Please feel free to stop by.

last updated Oct 30, 2026

Revolutionary product for threaded reinforcement! Accurate Tangless Insert

No 'g'!? Revolutionary product with metal insert: Accurate Tangless Insert.

last updated Oct 30, 2026

Ultra Spring (Standard Spring)

Standard springs with a rich variety of options are available at low prices from prototyping to mass production, priced per lot.

last updated Oct 30, 2026

Compression coil springs and tension coil springs "Ultra Spring" outer diameter index.

The "Ultra Spring" standard spring from Accurate comes with a lot number for all products, ensuring complete traceability!

last updated Oct 30, 2026