Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
When a worn-out spring causes a mechanism to fail — a stuck pen, a misfiring valve, a loose latch — finding the exact replacement size is the real challenge. These compression springs are designed for engineers, hobbyists, and repair technicians who need a reliable, dimensionally consistent spring in a compact form factor, without ordering a custom batch.
Each spring is manufactured from carbon steel wire with a uniform coil pitch and closed ends, available in wire diameters from 0.3mm to 1.6mm and outside diameters from 2mm to 25mm (approx. 0.08–0.98 in), all cut to a free length of 300mm (approx. 11.8 in). The wire cross-section and coil geometry are consistent across the range, making these suitable for precision applications.
Typical use cases include replacing compression springs in ballpoint pens and mechanical pencils, restoring tension in small electronic assemblies and PCB connectors, and providing return force in DIY jigs, fixtures, and custom tooling. The 300mm free length also makes these suitable for cutting-to-length applications where a specific compressed height is needed.
| Spring Type | Compression Spring |
|---|---|
| Wire Diameter Range | 0.3mm – 1.6mm (0.012 – 0.063 in) |
| Outside Diameter Range | 2mm – 25mm (0.08 – 0.98 in) |
| Free Length | 300mm (approx. 11.8 in) |
| End Type | Closed ends (See variant options) |
| Material | Carbon Steel |
| Surface Finish | See variant options |
| Spring Rate | See variant options |
| Load Capacity | See variant options |
| Coil Direction | Right-hand (standard) |
| Quantity per Order | 1 piece |
Wire diameter determines the stiffness and load capacity of the spring — a thicker wire produces a stiffer spring. Outside diameter (OD) must fit inside the bore or housing where the spring seats. As a rule: OD should be slightly smaller than the bore ID, and the inner diameter (ID = OD minus 2× wire diameter) should clear any guide rod. Select your wire diameter first based on the force you need, then match the OD to your housing dimensions.
Yes. The 300mm free length is intentionally long to allow cutting. Use a rotary tool or spring cutter to trim to your required free length. After cutting, the end coil may need light grinding to restore a flat seating surface. Note that cutting changes the spring rate proportionally — a shorter spring of the same wire and OD will be stiffer.
These springs are made from carbon steel, which offers good mechanical properties but limited corrosion resistance in wet or outdoor environments. For applications exposed to moisture, consider applying a light coat of machine oil or grease, or use them in enclosed, dry assemblies. If corrosion resistance is a primary requirement, contact us to confirm whether a coated or stainless variant is available.
Spring rate depends on wire diameter, outside diameter, free length, and number of active coils. Because these springs can be cut to length, the effective spring rate will vary by your final cut length. We do not publish a fixed spring rate per variant — if you need a calculated rate for a specific combination, contact us with your wire diameter, OD, and required free length and we can assist.
These springs are suited for light-to-medium load applications including: ballpoint pen and mechanical pencil mechanisms, PCB push-button and connector assemblies, small valve and actuator return springs, DIY jigs and clamping fixtures, hobby robotics and RC mechanisms, and general repair and prototyping work. They are not rated for heavy industrial or safety-critical load-bearing applications.
Inside diameter = Outside Diameter − (2 × Wire Diameter). For example, a spring with OD 10mm and wire diameter 1.0mm has an ID of 8mm. This is the clearance available for a guide rod or shaft. Always allow 0.2–0.5mm of clearance between the ID and any guide rod to prevent binding during compression.
Each order includes 1 piece of the selected spring variant. If you need multiple pieces or a bulk quantity, please contact us — we can accommodate larger orders for the same specification.
