Custom Precision Spring
Manufacturing.
Wire springs, flat springs, torsion, tension, wire forms, and long special springs — from ultra-fine micro coils to 2,000mm surgical instrument springs. Backed by TOHOSEIKO's 65+ years of Japanese spring engineering.
Custom QuoteOur Spring Products
Spring Capabilities & Specifications
Through our TOHOSEIKO partnership, SMI-CA offers the full spectrum of precision spring types — from ultra-fine micro coils finer than a human hair to long special springs for surgical instruments.
Ultra-precision compression springs, including coils finer than a human hair. Ideal for medical devices, PCB test fixtures, electronics testing, and optical equipment.
Precision torsion springs for applications requiring controlled rotational resistance. Used extensively in automotive transmission assemblies, industrial mechanisms, and consumer devices.
High-precision tension springs manufactured to exacting load and dimensional tolerances for reliable extension force performance across aerospace and industrial applications.
Complex wire form components crafted to custom geometries. Used in medical instruments, endoscope actuation, surgical tool mechanisms, and industrial assemblies.
Flat springs and multi-forming parts stamped from sheet metal to tight thickness tolerances. Used for contact, trigger, clamping, and electrical connection functions.
Long coil springs exceeding 2 meters and modified cross-section special springs (φ0.35–φ2.0mm) for endoscopes, laparoscopic instruments, and custom surgical applications.
The TOHOSEIKO Advantage
Japan's Precision Spring Engineering — In Your Supply Chain.
In 2018, TOHOSEIKO Co., Ltd. — one of Japan's foremost precision spring manufacturers — established an investment partnership with SMI CA, Inc. This brings capabilities unavailable from standard domestic spring suppliers directly to the North American aerospace and medical supply chain.
TOHOSEIKO's proprietary Temperboy spring tempering equipment, developed in-house since 1957, is the same technology SMI-CA uses to maintain process consistency and dimensional stability across production runs.
Learn more about TOHOSEIKO →Spring Materials
Springs are produced from a wide range of wire materials to meet the mechanical, electrical, and biocompatibility requirements of each application.
Industries Served
Custom Springs — Frequently Asked Questions
What types of custom springs do you manufacture?
We manufacture compression springs, tension springs, torsion springs, flat springs, wire forms, long special springs (up to 2,000mm), and multi-forming parts. Wire diameters from φ0.02mm to φ10mm through our TOHOSEIKO partnership, in stainless steel, titanium, Inconel, and specialty alloys.
Do you make precision springs for aerospace applications?
Yes. We supply actuation springs, compression coils, and wire forms for aerospace and defense applications under AS9100D quality management. Materials include stainless steel (302, 304, 17-7 PH), titanium (Ti-6Al-4V), and Inconel for high-temperature aerospace environments.
Can you make springs for medical devices and surgical instruments?
Yes. We produce long special springs up to 2,000mm for endoscope coil sheaths, compression springs for surgical instrument actuation, and wire forms for minimally invasive device assemblies. Biocompatible materials (316L stainless, Ti-6Al-4V) available with full material lot traceability.
What is the minimum wire diameter you can manufacture springs from?
Through our TOHOSEIKO partnership, we can manufacture springs from wire diameters as fine as φ0.02mm — used for optical device lens actuators, autofocus mechanisms, and ultra-precision electronics. Standard production for medical and aerospace typically starts from φ0.08mm.
Do you offer spring prototyping and small-batch production?
Yes. We support prototype through full production runs. Share your wire diameter, spring type, free length, load requirements, and target volume and we'll provide a quote. Our Santa Fe Springs, CA facility serves customers across Los Angeles, Orange County, and throughout Southern California.
Have a spring application to discuss?
Share your wire diameter, spring type, load requirements, and production volume. We'll respond with a quote backed by 65+ years of precision spring manufacturing expertise.
Custom QuotePhone: +1 (562) 926-9407 | Email: dok@smi-ca.com