- Stock: 866
- Model: Muelle-niquel-7.5x20
Model:
ID 4mm Cut To Size
M3 or M4 - 7.5x20
Helical compression spring made from nickel-plated steel, with a 7.5 mm outside diameter, 5 mm inside diameter and 20 mm nominal free length. It can be used to apply pressure, return a component to position or maintain tension in small mechanical assemblies for 3D printers, CNC machines, automation systems and DIY projects.
Its 5 mm inside diameter allows it to fit around M3 and M4 screws, rods or guides. This is dimensional compatibility only: preload, available travel and the force required by the mechanism must also be checked before installing it in a machine.

Dimensions and characteristics
- Type: helical compression spring.
- Material: nickel-plated steel.
- Nominal outside diameter: 7.5 mm.
- Nominal inside diameter: 5 mm.
- Nominal uncompressed length: 20 mm.
- Inside clearance dimensionally suitable for M3 and M4 screws or guides.
- Quantity: 1 piece.
Typical applications
- Adjustment and levelling systems when its dimensions and force are suitable.
- Tension mechanisms for extruders and other moving assemblies.
- Compliant stops, return mechanisms and small pressure assemblies.
- Prototypes, 3D printers, small CNC machines and automation projects.
How to check suitability
The spring rate, maximum load and solid height are not specified. It should therefore not be selected by dimensions alone where the application requires a calibrated force, guaranteed travel or a safety function.
- Check that the 7.5 mm outside diameter fits the available housing.
- Verify that the 5 mm bore provides the required guidance or clearance.
- Check the space available with the spring both free and compressed.
- Avoid compressing it until all coils are fully closed.
- Test the mechanism manually before operating it at speed or under load.
If a different length is required for a non-calibrated assembly, see the cut-to-length compression spring and compare its inside diameter with the requirements of the assembly.
Package contents
- 1 × nickel-plated steel compression spring, 7.5 × 20 mm.