- Propeller + sweeping—five minutes for a standard compression spring.
- The dead coils (ground ends) are made with a variable-pitch propeller.
- A spring is useful in an assembly only if it is flexible : That's the part we tend to forget.
A spring is modeled in three steps: a circular sketch with the diameter of the spring, a Propeller (Insert → Curve → Helix and Spiral), which defines the pitch and the number of turns, followed by a Scanning with a circular cross-section (wire diameter) along the helix. The result is a fixed spring; to allow it to compress within an assembly, the pitch or height is made adjustable via an assembly dimension.
The Steps
- On the top view, sketch a circle at the average diameter the spring's diameter (outer diameter minus the wire diameter).
- Insert → Curve → Helix and Spiral. Define by: Pitch and number of turns (e.g., pitch 5 mm, 8 turns), direction (clockwise), starting angle 0°.
- On a plane perpendicular to the propeller's point of origin (usually the front view), sketch a circle at the wire diameter, centered on the tip of the propeller. Tip: «Mark» the propeller’s tip on the drawing to center it exactly.
- Features → Scan : profile = the small circle, trajectory = the helix. Confirm.
- Ends: For ground windings, select the following for the helix Variable step size and use a smaller pitch on the first and last turns, then trim the ends with a Extruded Material Removal flat.
Making the spring flexible in the assembly
- In the spring section, specify the clear height (or pitch) and give it a descriptive name (e.g.,.
Height). - Insert the spring into the assembly and secure it at both supports.
- Right-click on the spring → Make the part flexible, then link the dimension
Heightthe distance between the two supports. The spring then follows the movement.
The Pitfall to Watch Out For
The sweep will fail if the wire profile is too large for the pitch (the coils overlap) or if the profile is not exactly at the start of the helix. Verify that the wire diameter is less than the pitch, and use «Drill» rather than approximate centering.
FAQ
Frequently asked Questions
How do you make a tension or torsion spring?
The same principle (helix + sweep) applies, with a pitch equal to the wire’s diameter (adjacent coils) for traction, plus the hooks modeled by separate sweeps. Torsion adds straight segments at the ends.
The spring is slowing down my assembly—what should I do?
A compressed spring is difficult to calculate. In the assembly, display it in a simplified configuration (cylinder) and show the actual spring only in the renderings.
Further Reading : Find All of our SOLIDWORKS tutorials and the SOLIDWORKS Training by Ohmytraining.
