Compression Spring Wire Dia 0.4mm OD 3mm 304 Stainless Steel Vibration Damping

Measure the distance between the two seating surfaces in your assembly when the spring is at its natural (uncompressed) state. Add your required compression travel to that distance to get the minimum free length you need. For vibration damping, a free length 1.5–2× the compressed working length is a common starting point. Select the variant whose free length is closest to or slightly longer than your calculated value.

Due to the small wire cross-section (0.4 mm), these springs are designed for light-duty applications — typically in the range of a few grams to a few hundred grams of force depending on free length and compression ratio. They are not intended for heavy structural loads. If you need exact spring rate or load data for a specific length, please contact us to confirm before ordering.

Yes. 304 stainless steel offers solid resistance to atmospheric corrosion, moisture, and mild chemical exposure. It is suitable for indoor humid environments, light outdoor use, and applications where occasional water contact is expected. For highly corrosive environments (saltwater immersion, strong acids), consider 316 stainless steel instead.

For a guide shaft (inner guide), the shaft diameter should be smaller than the inner diameter — approximately ≤ 2.0 mm to allow free compression without binding. For a bore (outer guide), the bore diameter should be ≥ 3.1–3.2 mm to provide clearance. Always allow 0.1–0.2 mm clearance on each side to prevent coil-to-wall friction during compression.

Yes — these are a popular choice for pen click mechanisms, tactile switch return springs, keyboard stabilizer springs, and small electronic actuators. The 0.4 mm wire diameter and 3 mm OD fit many standard pen barrel and switch housing dimensions. Verify the free length and stroke against your specific mechanism before ordering.

For prototyping or testing a new design, start with 10 pcs to validate fit and performance before committing to larger quantities. For small-batch production runs (10–50 units of your product), 50 pcs or 100 pcs offers a lower per-unit cost and reduces reorder frequency. Bulk quantities are also useful for workshop stock when you use the same spring size across multiple projects.

The 5–100 mm variants are standard short-to-medium compression springs suited for return mechanisms, switch actuators, and vibration damping in compact assemblies. The 305 mm (≈12 in) variant is a long spring intended for applications requiring extended travel or higher energy storage — such as long-stroke dampers, suspension mockups, or custom fixtures. Note that the 305 mm variant has different quantity options (1–30 pcs) reflecting its larger size.