Compression Spring Steel 0.3mm Wire Dia 2mm - 8mm OD Small Pressure Springs

Measure the inner diameter of the bore or pocket where the spring will seat, then select an OD that is slightly smaller — typically 0.1mm to 0.3mm clearance. For a shaft-guided spring, measure the shaft OD and select an ID (inner diameter = OD minus twice the wire diameter) that provides a snug but non-binding fit. Use the variant selector above to choose from 2mm, 2.5mm, 3mm, 4mm, 5mm, 6mm, 7mm, or 8mm OD.

With 0.3mm wire, these are light-duty compression springs suited for applications requiring gentle return force — such as button contacts, pen clips, small latches, and miniature switch mechanisms. They are not designed for heavy structural loads. If your application requires significant force, consider a heavier wire gauge. Contact us to confirm suitability for your specific load requirements.

These springs are formed from steel wire. Standard steel offers good mechanical properties but has limited corrosion resistance in humid or wet environments without additional surface treatment. For outdoor or moisture-exposed applications, consider applying a light coat of machine oil or using them in a protected enclosure. If corrosion resistance is a primary requirement, contact us to confirm the available finish options.

Yes. The range of OD options (2mm–8mm) and free lengths (5mm–50mm) makes these springs well-suited for integration into 3D-printed spring pockets, snap-fit assemblies, and custom DIY enclosures. Design your pocket to match the selected OD with 0.1–0.3mm clearance and ensure the pocket depth accommodates the compressed length of the spring under maximum load.

Free length is the uncompressed length of the spring. To select the right length: (1) determine the maximum travel (stroke) your mechanism requires, (2) add the compressed solid height (approximately wire diameter × number of coils), and (3) add any required preload length. Choose the free length option from the variant selector that meets or slightly exceeds this calculated value. Available lengths run from 5mm to 50mm in 5mm steps.

Each variant is sold as a pack of 10 identical springs. This is useful for prototyping (test multiple configurations), repair kits (keep spares on hand), and multi-unit builds where you need the same spring in several positions. Select your desired Wire Diameter, Outer Diameter, and Length combination above, then add to cart.

For standard ballpoint pen mechanisms, a 2mm–3mm OD spring with a 10mm–20mm free length is typically appropriate. For retractable tool clips or larger button mechanisms, 4mm–6mm OD springs in 15mm–30mm lengths are more common. Always verify against your specific component dimensions. The variant selector lets you mix and match OD and length to find the exact fit.