# Plymouth Spring Company, Inc.

This MFR.ID profile was supplied, reviewed, and approved by Plymouth Spring Company, Inc.. Originally approved on 8/18/2025; last updated 8/18/2025. Capability data is manufacturer-approved for public sourcing and RFQ use.

## Profile Links

- Canonical profile: https://mfr.io/plymouthspring
- JSON data: https://mfr.io/plymouthspring.json

## Company Overview

Founded in 1959, Plymouth Spring Company, Inc. is a Connecticut-based custom manufacturer of precision springs, wire forms, and fourslide stampings. Now part of Lesjöfors AB (Beijer Alma), Plymouth Spring operates a single 80,000-sq-ft facility in Bristol equipped with 36+ CNC coiling machines, multislide presses, and full in-house tooling. Serving more than 600 customers across aerospace, defense, automotive, medical, electronics, consumer, and industrial markets, the company is ISO 9001:2015 certified, ITAR-registered, and compliant with RoHS and REACH. With about 55 employees, annual revenue of USD 10–25 million, and typical lead times of three to four weeks, Plymouth Spring supports lean, Kanban, and JIT programs to deliver high-volume runs of custom metal components worldwide.

## Quick Reference

- Processes: Spring Wire Forming, Fourslide Stamping, Wire Forming, Value Added Services
- Lead Time: 3-4 weeks
- Production Scale: Prototype (1-10 parts), Short Run (11-500 parts), Medium Run (501-10000 parts), Mass Production (10001+ parts), Prototype (1-100 parts), Short Run (101-10000 parts), Medium Run (10001-500000 parts), Mass Production (500001+ parts), Prototype (1-50 parts), Short Run (51-5000 parts), Medium Run (5001-500000 parts)
- Location: Bristol, Connecticut 06010
- Employees: 51-100
- Revenue: $10M-$25M
- Founded: 1959
- Contact: kjohnson@plymouthspring.com - +1 860-584-0594
- Verified: Manufacturer Approved

## Capabilities

### Custom Spring Manufacturing

Plymouth Spring coils precision compression, extension, torsion, and specialty springs on 36 CNC machines, then finishes them with in-house end-grinding, stress-relieving, shot-peening, and SPC-backed load testing. The cell delivers ±0.005 in critical-diameter accuracy and ±5 % spring-rate repeatability from single prototypes to multi-million-piece runs.

- Process: Spring Wire Forming
- Highlights: 36 CNC coilers cover Ø 0.006–0.197 in wire, In-house end grind, hook/loop forming, custom tooling, Inline stress-relief & shot peening boost fatigue life, ISO 9001 + SPC hold ±0.005 in dimensions, Prototype-to-JIT: 1 piece to millions, 3–4 week lead
- Subprocesses: CNC Spring Coiling, Spring End Configuration, Spring End Grinding, Heat-Treating & Thermal Processing, Shot Peening, Inspection & Quality Control
- Specifications:
  - Free Length Range: 0.12-51.2 in (3-1300 mm) - Ability to make very long constant-force / clock springs alongside short precision coils.
  - Critical Diameter Tolerance: 0.005 in - Tight ID/OD control ensures drop-in fit for valve-train seats and cartridge assemblies.
  - CNC Coilers In Cell: 36 machines - Large coiler fleet enables parallel setups—quick changeovers for prototypes alongside high-volume jobs.
  - Spring Types: Compression, Extension, Torsion, Constant-force, Conical, Barrel, Double torsion - Broad catalog enables designers to consolidate all spring variants with one supplier.
  - Wire Diameter Range: 0.006-0.197 in (0.15-5 mm) - Covers ultra-fine electronics springs through heavy industrial loads without hot-coiling.
  - Production Scale: Prototype (1-10 parts), Short Run (11-500 parts), Medium Run (501-10000 parts), Mass Production (10001+ parts) - Single supplier from EVT to mass production eliminates re-qualification and PPAP duplication.
  - Spring Rate Tolerance: Metric: -5-5 % - ±5 % rate repeatability meets typical firearm and medical device specs without extra sorting.
  - Mean Coil Diameter Range (Typical): 0.08-2 in (2-50 mm) - Typical envelope supports most firearm, medical, and consumer device springs; larger ODs via Lesjöfors partners.
  - Typical Lead Time: 21-28 days - Standard 3–4 week window; JIT/Kanban programs cut effective customer wait to next-day releases.

### Fourslide Stamping

High-speed fourslide presses punch, bend, coin, emboss, and tap strip or wire in one pass, producing up to 10 000 precision clips, contacts, and flat springs per hour. In-house CAD/CAM tooling, ISO 9001 SPC, and ±0.003 in dimensional control support runs from a single prototype through multi-million-piece programs, with repeat orders shipping in 3–4 weeks.

- Process: Fourslide Stamping
- Highlights: Up to 10 000 parts/hr on multi-slide presses, Complex bends, holes, threads in one operation, In-house CAD-driven tooling accelerates launches, ISO 9001 + SPC hold ±0.003 in repeatability, Prototype to millions; repeat lead 3–4 wk
- Subprocesses: Metal Stamping, Coining, Embossing, Tapping, Tool & Die (Fixtures & Gages), Deburring
- Specifications:
  - Flat Blank Length (Max): 15 in (381 mm) - Beyond this length, progressive-die stamping or secondary forming is recommended.
  - Strip Width Range: 0.004-2.3 in (0.1-63.5 mm) - Maximum width constrained by slide travel and feed-straightener width.
  - Typical Repeat Lead Time: 14-28 days - Tooling retained in-house; JIT/Kanban programs can reduce customer wait to 0–1 day.
  - Maximum Production Speed: 10000 parts_per_hour - Benchmark rate on 0.020 in brass clip; actual speed varies with part complexity.
  - Production Scale: Prototype (1-100 parts), Short Run (101-10000 parts), Medium Run (10001-500000 parts), Mass Production (500001+ parts) - Multi-shift scheduling supports sustained >1 M pieces/month when required.
  - Wire Diameter Range: 0.01-0.1875 in (0.25-4.8 mm) - Round-wire feed for formed pins, contacts, and spring clips.
  - Strip Thickness Range: 0.005-0.1 in (0.127-2.54 mm) - Typical fourslide envelope; thicker stock handled on power press if required.
  - Dimensional Tolerance: 0.003 in - Critical features routinely held to ±0.003 in; tighter attainable with SPC and dedicated gauging.

### Custom Wire Forming & Precision Pins

Plymouth Spring shapes wire into 2-D/3-D hooks, clips, rings, shafts, and ultra-precise pins with multi-axis CNC benders, fourslide formers, and cut-off/rolling lines. Machines handle 0.006–0.160 in wire and output up to 50 million parts with ±0.005 in length and ±1° bend accuracy. In-house tooling, heat treat, threads, and SPC ensure medical- and aerospace-grade consistency in 3–4 week repeats.

- Process: Wire Forming
- Highlights: CNC benders create complex 2-D/3-D shapes, Wire Ø 0.006–0.160 in; ±1° bend accuracy, Straight pins cut/ground to ±0.005 in, Threads, notches, swaging in-line, Prototype to 50 M+ pieces; 3–4 wk repeat
- Subprocesses: Wire Forming, Forming, Metal Stamping, Rolling, Tapping, Heat-Treating & Thermal Processing, Inspection & Quality Control
- Specifications:
  - Typical Repeat Lead Time: 21-28 days - Prototype lots can ship in 1 week; JIT/Kanban inventory reduces customer wait to <1 day.
  - Maximum Production Speed: 6000 parts_per_hour - Simple cotter pins on high-speed lines; complex forms run slower.
  - Maximum Part Length (One Piece): 1.5 in (38 mm) - Longer components can be produced via progressive forming or welded assemblies.
  - Production Scale: Prototype (1-50 parts), Short Run (51-5000 parts), Medium Run (5001-500000 parts), Mass Production (500001+ parts) - 24/7 multi-shift capacity supports >4 M pieces/month when required.
  - Pin Length Tolerance: 0.005 in - Cut-off and centerless grind with laser micrometer feedback achieve ±0.005 in.
  - Thread Size Capability: #2-56 to 1/4-20 (M2–M6 metric equivalent) - Threads rolled or tapped in-line; larger sizes on request.
  - Bend Angle Accuracy: 1 deg - Servo-controlled CNC heads and optical comparators verify ±1° on critical bends.
  - Wire Diameter Range: 0.006-0.16 in (0.15-4.06 mm) - Standard CNC envelope; larger diameters available through group hot-forming partners.

### Secondary & Value-Added Services

Beyond core forming operations Plymouth Spring adds in-house heat-treat, deburr/finish, coating, assembly, custom packaging, and inventory programs. These services shorten supply chains, deliver PPAP/traceability, and support JIT releases—so springs, stampings, or wire forms arrive ready for the line with zero additional processing.

- Process: Value Added Services
- Highlights: Low-temp stress-relief & austemper ovens in-house, Vibratory deburr, shot-peen, surface conditioning, 10+ finishes: black oxide, Zn, Ni, powder, anodize, Light assembly, ESD/rod/kit packaging, bar-coding, JIT / Kanban inventory stocked up to 12 months
- Subprocesses: Heat-Treating & Thermal Processing, Deburring, Surface Conditioning, Coating Processes, Light Mechanical Assembly, Packaging / Kitting, Inventory Management & Logistics, Tool & Die (Fixtures & Gages), Engineering & Design Services, Inspection & Quality Control
- Specifications:
  - Kanban / JIT Release Lead Time: 0-1 days - Stocked product ships same-day on electronic pull signal.
  - Heat Treat Methods: Low-temperature stress-relief, Austempering for high-carbon steels - Optimises spring temper and wire-form fatigue life without distortion.
  - Inventory Stock Duration (Max): 12 months - Blanket orders stored free for up to one year for pull releases.
  - Finishes & Coatings Supported: Black oxide, Zinc plating (clear/yellow), Nickel plating, Cadmium plating, Electroless nickel, Anodize, Powder coat / paint, Gold or silver flash - All RoHS/REACH compliant options; NADCAP coaters used for aerospace parts.
  - Custom Packaging Piece Count Range: 1-10000 pieces (1-10000 pieces) - Bag, tube, or on-rod counts defined per BOM; larger bulk in gaylords or reels.

## Certifications

- REACH Compliance (Type: Compliance; Authority: European Chemicals Agency (ECHA); Status: Active; Scope: REACH chemicals compliance.; URL: https://environment.ec.europa.eu/topics/chemicals/reach-regulation_en)
- ISO 9001:2015 (Type: Certification; Authority: International Organization for Standardization (ISO); Status: Active; Scope: Manufacture and assembly of springs, stampings, four-slide parts and precision pins.; Issue date: 2024-03-30; Expiration date: 2027-03-29; URL: https://www.iso.org/iso-9001-quality-management.html)
- ITAR Registration (Type: Registration; Authority: U.S. Department of State – Directorate of Defense Trade Controls (DDTC); Status: Active; Scope: ITAR registration authorising manufacture/export of defence articles.; Issue date: 2024-08-01; Expiration date: 2025-07-31; URL: https://www.pmddtc.state.gov)
- RoHS 3 Compliance (Type: Compliance; Authority: European Commission; Status: Active; Scope: Restriction of hazardous substances compliance.; URL: https://ec.europa.eu/environment/topics/waste-and-recycling/rohs-directive_en)
- EcoVadis Sustainability Rating (Type: Accreditation; Authority: EcoVadis; Status: Active; Scope: EcoVadis sustainability assessment membership.; URL: https://ecovadis.com)
- Worldfavor ESG Rating (Type: Accreditation; Authority: Worldfavor; Status: Active; Scope: Worldfavor ESG performance platform participation.; URL: https://worldfavor.com)
- Spring Manufacturers Institute (SMI) Membership (Type: Membership; Authority: Spring Manufacturers Institute (SMI); Status: Active; Scope: Active SMI trade-association membership.; URL: https://smihq.org)
- New England Spring & Metalstamping Association (NESMA) Membership (Type: Membership; Authority: New England Spring & Metalstamping Association (NESMA); Status: Active; Scope: Active NESMA regional membership.; URL: https://nesma-usa.com)

## Industries Served

- Aerospace & Defense: Supplies flight-critical torsion springs, wire forms and stamped components for aerospace platforms under ITAR and DFARS requirements.
- Automotive & Transportation: Manufactures seat-recliner torsion springs, throttle springs and wire forms for OEM and Tier-1 automotive suppliers, supporting PPAP documentation.
- Medical Devices & Healthcare Equipment: Produces tight-tolerance springs and wire forms for surgical instruments, diagnostic equipment and other ISO 13485-aligned medical devices.
- Industrial Machinery & Heavy Equipment: Designs and forms durable springs, clips and counter-balance mechanisms for industrial machinery and heavy-equipment assemblies.
- General Manufacturing: Provides versatile spring and stamping solutions for diverse general-manufacturing projects requiring rapid customisation.
- Electronics & Semiconductors: Supplies battery contacts, EMI-shield clips and precision springs for electronic assemblies and PCB hardware.
- Consumer Goods & Appliances: High-volume custom springs and clips for consumer appliances, sporting equipment and household products.
- Construction Products & Building Materials: Manufactures tension springs, brackets and clips used in construction tools, fixtures and building hardware.
- Food & Beverage Processing: Produces food-grade springs and wire forms for conveyors, packaging and processing machinery.
- Marine & Shipbuilding: Forms corrosion-resistant springs and hardware for marine decking, boat hardware and offshore equipment.
- Pharmaceuticals & Biotechnology: Supplies precision springs and clips for pharmaceutical processing, lab equipment and dosing devices.
- Plumbing & Flow Control: Manufactures springs, clips and stamped parts for valves, faucets and plumbing flow-control hardware.
- Power Distribution & Switchgear: Fabricates contact springs and high-voltage clips for switchgear, breakers and power-distribution systems.
- Security & Surveillance Equipment: Produces springs and wire forms for locks, access-control devices and security-hardware assemblies.
- Sporting Goods: Custom springs and metal parts for sporting-goods equipment, training devices and recreational gear.
- Telecommunications: Precision clips and springs for telecom connectors, cable assemblies and network-infrastructure hardware.

## Facilities

### Plymouth Spring Headquarters & Manufacturing

An 80,000-sq-ft single-story plant housing CNC coiling, multislide stamping, wire forming, and toolmaking. Emphasises lean manufacturing, JIT, and energy-efficient processes for quick-turn, high-volume production.

- Type: manufacturing_facility
- Headquarters: Yes
- Email: sales@plymouthspring.com
- Phone: +1 860-584-0594
- Address: 281 Lake Avenue, Bristol, Connecticut 06010, United States

## Verification Status

- Business Entity: Verified 7/10/2025
- Technical Capabilities: Verified 8/18/2025
- Locations & Facilities: Verified 8/18/2025
- Reviews & Ratings: Not yet verified
- MFR.ID Created: 6/2/2025
- Last Updated: 8/18/2025