Touch Springs
Touch springs that hold contact,
part after part.
Conductive contact springs formed to your drawing in Rayong, Thailand — from 0.08 mm wire for compact panels and PCB contacts to 8.0 mm for heavier terminal assemblies. New equipment will extend the range to 12.0 mm.
Contact force and travel, set by the drawing
A touch spring does two jobs at once. It carries current through a compliant contact, and it holds a predictable force at the height the assembly closes to. Both come from the wire, the coil and the free length — not from a catalogue.
We form the coil and its tail or pin to your drawing, then check the finished part at the working height you specify. Wire is checked for tensile strength and metallographic structure before production; finished parts are load-tested and measured before packing.
- Wire diameters from 0.08 mm to 8.0 mm in current production
- Coil body with straight tail, pin or loop contact, as drawn
- Stainless steel and carbon spring steel grades
- Prototype, pre-production and volume orders
Where touch springs make the connection
A contact spring sits between a PCB and whatever the user touches or the housing carries — a panel, a shield can, a battery terminal or a connector body. The gap it bridges and the force it holds decide the design.
Touch spring specifications
Current production is shown below. If your part falls outside these parameters, we review it at RFQ rather than assume the answer.
| Parameter | Capability |
|---|---|
| Wire diameter | 0.08–8.0 mm in current production. Planned expansion to 12.0 mm as new equipment is installed. |
| Materials | Stainless steel 301, 302, 304 and 316; 65Mn, 72A, 82B and 60Si2Mn carbon spring steels. Other grades reviewed on request. |
| Contact form | Coil body with straight tail, pin or loop, as defined on the drawing. |
| Working height and load | Measured at the compressed height stated on the drawing; force tolerance agreed at RFQ. |
| Heat treatment | In-house stress relief and tempering. |
| Surface finish | Anti-rust oil, electrophoresis (E-coat), zinc plating, nickel plating, spray coating. |
| Wire tolerance | JIS wire tolerance by grade (JIS G 3521, JIS G 3522 or JIS G 4309). ASTM wire specification and SMI commercial tolerances available for US programs. |
| Dimensional inspection | 2.5D vision measurement and dimensional checks against the drawing. |
| Corrosion testing | Salt spray testing for plated and coated parts. |
| Quality system | ISO 9001:2015 and ISO 14001:2015. |
| Samples | Prototype and pre-production samples against drawing. |
Contact resistance and plating requirements should be stated on the drawing. We confirm the finish, the test method and the inspection plan at RFQ before quoting.
Materials and finishes
The wire grade and finish follow the contact force, the number of mating cycles and the corrosion exposure of the assembly.
301 · 302 · 304 · 316
Used where the contact sees moisture, cleaning or a corrosive environment, and where a plated finish is not wanted. Grade and wire diameter are matched to the force required.
65Mn · 72A · 82B · 60Si2Mn
Selected for higher strength and fatigue life at a lower material cost, normally with a plated or coated finish for corrosion protection.
Nickel · zinc · E-coat · oil · spray
Nickel plating, zinc plating, electrophoresis, anti-rust oil and spray coating are available. The finish is chosen for contact requirement and environment.
Checked at the height the part works at
Load, dimensions and material condition are measured in-house before shipment. The inspection and test plan is agreed at RFQ.
- Raw material tensile strength and metallographic structure
- Load and compression testing on automatic spring testers
- 2.5D vision measurement of contact geometry
- Salt spray testing for plated and coated parts
- Fatigue testing for cycle-life validation
- Inspection records agreed at RFQ
What to send with your drawing
A complete drawing shortens the quote and removes assumptions about force and finish.
- Wire diameter, material grade and finish
- Coil outside diameter and free height
- Working height and the force required at it
- Tail, pin or loop geometry
- Contact resistance or mating-cycle target, if specified
- Annual quantity and delivery schedule
PDF, DXF, STEP or a clear photo
Email your drawing to info@aofengspringthailand.com. We confirm the wire range, material, finish and test plan before quoting.
Touch spring questions
What is a touch spring?
A touch spring is a formed spring that provides a compliant electrical contact between two surfaces — typically a PCB and a panel, shield can, battery terminal or connector. The spring keeps the contact closed as the assembly moves and tolerances stack up.
Which materials and finishes do you use?
Stainless steel 301, 302, 304 and 316, plus 65Mn, 72A, 82B and 60Si2Mn carbon spring steels. Finishes are anti-rust oil, electrophoresis, zinc plating, nickel plating and spray coating, chosen for the contact and corrosion requirement.
How is contact force controlled?
Force is designed from wire diameter, coil diameter, active turns and free length. The finished part is then measured and load-tested at the working height stated on the drawing.
Can you supply samples before production?
Yes. We produce prototype and pre-production samples against the drawing, then validate the part and the inspection plan before volume production.
Send a drawing, get a quote
Tell us the working height, the force and the finish. We will confirm the wire range, material and test plan before quoting.
AOFENG SPRING (THAILAND) · Rayong, Thailand