Custom Straight-Leg Torsion Springs Manufacturer

About Custom Straight-Leg Torsion Springs

Straight-leg torsion springs are often the cleanest form for rotational return because the legs can bear against uncomplicated stops. Unlike compression or extension springs, the important output is torque at angle. Coil fit on the shaft, winding direction and leg contact positions all affect the working condition.

Key Design Characteristics

The spring should be loaded in the intended winding direction so the coil behaves predictably on its mandrel.
Leg length changes the contact force at the end even when spring torque is unchanged.
The coil ID must allow movement on the shaft as the spring winds and its diameter changes slightly.
Free angle and working angles should be referenced to clear datums on the assembly.

What to Specify for a Custom Quote

Wire diameter, coil ID or mandrel diameter, and body width
Free leg angle and required working angles
Torque at one or more angular positions
Length and contact point of each straight leg
Winding direction, cycles, temperature, material and quantity

Manufacturing Review

Torque testing should be tied to defined angles and a defined leg contact radius. Checking only free angle is not enough when the customer needs a repeatable torque curve.

Common Assembly Roles

Hinge return
Lever and pedal return
Rotary clamp or latch bias

Product Data

Typical Spring Configurations

Use these data points to compare practical starting dimensions and material options. Final production specifications are confirmed against your drawing and working conditions.

Model	Wire dia.	OD	ID	Free length	Rate	Material	Coils	Max load
ST-500-0323-0630-0669	5 mm	32.31 mm	22.31 mm	63.02 mm	108.038	Music Wire (SWP-B)	11.9	7767.92
ST-250-0359-0250-0696	2.5 mm	35.89 mm	30.89 mm	25.02 mm	3.388	Phosphor Bronze (QSn4-0.3)	9.7	580.99
ST-040-0048-0038-0645	0.4 mm	4.77 mm	3.97 mm	3.79 mm	0.019	Phosphor Bronze (QSn4-0.3)	8.8	1.13
ST-250-0323-0349-0598	2.5 mm	32.3 mm	27.3 mm	34.87 mm	5.111	304 Stainless Steel	13.5	734.89
ST-060-0063-0087-0717	0.6 mm	6.33 mm	5.13 mm	8.72 mm	0.088	65Mn Spring Steel	14.4	15.12
ST-180-0137-0204-0609	1.8 mm	13.68 mm	10.08 mm	20.38 mm	4.683	Music Wire (SWP-B)	10.6	540.9
ST-400-0248-0735-0653	4 mm	24.78 mm	16.78 mm	73.47 mm	40.237	Oil-Tempered Spring Wire (SWO)	17.2	7097.89
ST-080-0110-0041-0607	0.8 mm	10.99 mm	9.39 mm	4.14 mm	0.489	Inconel X-750	4.8	50.88
ST-600-0512-0343-0699	6 mm	51.22 mm	39.22 mm	34.34 mm	309.736	Inconel X-750	5.4	23385.08
ST-080-0124-0134-0610	0.8 mm	12.42 mm	10.82 mm	13.36 mm	0.122	316 Stainless Steel	15.2	14.85
ST-040-0057-0038-0644	0.4 mm	5.74 mm	4.94 mm	3.75 mm	0.03	Carbon Spring Steel Wire (SWC)	9.1	5.32
ST-030-0016-0034-0602	0.3 mm	1.62 mm	1.02 mm	3.42 mm	0.031	Music Wire (SWP-A)	11.1	3.61
ST-400-0315-0583-0668	4 mm	31.52 mm	23.52 mm	58.27 mm	39.292	Carbon Spring Steel Wire (SWC)	13.3	4585.38
ST-250-0229-0119-0615	2.5 mm	22.9 mm	17.9 mm	11.89 mm	24.448	Carbon Spring Steel Wire (SWC)	4.4	4009.46
ST-100-0081-0147-0680	1 mm	8.06 mm	6.06 mm	14.68 mm	0.511	304 Stainless Steel	14.6	49.99
ST-050-0054-0066-0688	0.5 mm	5.41 mm	4.41 mm	6.64 mm	0.059	Music Wire (SWP-A)	12.1	7.91
ST-500-0468-0858-0627	5 mm	46.78 mm	36.78 mm	85.82 mm	52.198	Music Wire (SWP-B)	16.1	2876.09
ST-100-0092-0167-0718	1 mm	9.23 mm	7.23 mm	16.69 mm	0.435	Inconel X-750	16.3	19.53
ST-120-0141-0106-0670	1.2 mm	14.13 mm	11.73 mm	10.55 mm	1.088	Inconel X-750	8.6	187.07
ST-200-0158-0360-0656	2 mm	15.84 mm	11.84 mm	36.02 mm	3.608	60Si2MnA Spring Steel	18	156.59
ST-100-0152-0084-0622	1 mm	15.2 mm	13.2 mm	8.45 mm	0.501	65Mn Spring Steel	7.9	37.86
ST-150-0196-0149-0597	1.5 mm	19.65 mm	16.65 mm	14.86 mm	1.649	60Si2MnA Spring Steel	9.5	196.94
ST-200-0175-0255-0604	2 mm	17.51 mm	13.51 mm	25.54 mm	2.356	Phosphor Bronze (QSn4-0.3)	12.3	358.32
ST-400-0345-0206-0640	4 mm	34.48 mm	26.48 mm	20.57 mm	49.149	Phosphor Bronze (QSn4-0.3)	4.8	2010.21
ST-060-0067-0124-0620	0.6 mm	6.72 mm	5.52 mm	12.37 mm	0.062	60Si2MnA Spring Steel	19.3	7.21
ST-200-0228-0389-0635	2 mm	22.8 mm	18.8 mm	38.87 mm	2.251	Carbon Spring Steel Wire (SWC)	19.2	96.78
ST-040-0061-0050-0691	0.4 mm	6.09 mm	5.29 mm	5.04 mm	0.022	Music Wire (SWP-A)	11.5	1.17
ST-030-0052-0015-0595	0.3 mm	5.19 mm	4.59 mm	1.46 mm	0.012	Beryllium Copper (QBe2)	4.7	0.63
ST-180-0119-0310-0708	1.8 mm	11.94 mm	8.34 mm	30.97 mm	3.776	Inconel X-750	16	607.57
ST-180-0231-0235-0681	1.8 mm	23.07 mm	19.47 mm	23.54 mm	1.436	Beryllium Copper (QBe2)	12	122.32
ST-050-0052-0098-0639	0.5 mm	5.19 mm	4.19 mm	9.77 mm	0.041	Inconel X-750	18.8	1.92
ST-040-0033-0073-0685	0.4 mm	3.29 mm	2.49 mm	7.32 mm	0.018	Beryllium Copper (QBe2)	17.2	1.46
ST-180-0254-0294-0692	1.8 mm	25.42 mm	21.82 mm	29.42 mm	0.832	Phosphor Bronze (QSn4-0.3)	15	119.09
ST-120-0132-0224-0617	1.2 mm	13.21 mm	10.81 mm	22.37 mm	0.557	Music Wire (SWP-B)	17.4	94.21
ST-150-0195-0072-0672	1.5 mm	19.54 mm	16.54 mm	7.22 mm	1.677	Phosphor Bronze (QSn4-0.3)	4.7	53.5
ST-050-0062-0021-0650	0.5 mm	6.17 mm	5.17 mm	2.13 mm	0.147	Oil-Tempered Spring Wire (SWO)	4.2	14.85
ST-030-0037-0031-0630	0.3 mm	3.66 mm	3.06 mm	3.12 mm	0.013	316 Stainless Steel	9.5	0.48
ST-200-0266-0357-0657	2 mm	26.57 mm	22.57 mm	35.71 mm	1.095	Phosphor Bronze (QSn4-0.3)	16.7	138.01
ST-200-0220-0139-0695	2 mm	21.99 mm	17.99 mm	13.87 mm	6.195	304 Stainless Steel	6.8	975.12
ST-150-0119-0246-0600	1.5 mm	11.94 mm	8.94 mm	24.56 mm	0.851	Phosphor Bronze (QSn4-0.3)	16	135.53
ST-400-0170-0256-0719	4 mm	16.99 mm	8.99 mm	25.63 mm	164.644	304 Stainless Steel	6.3	5038.1
ST-150-0083-0062-0716	1.5 mm	8.29 mm	5.29 mm	6.16 mm	10.216	Carbon Spring Steel Wire (SWC)	4.1	496.49
ST-400-0456-0282-0649	4 mm	45.65 mm	37.65 mm	28.16 mm	52.317	Carbon Spring Steel Wire (SWC)	6.6	6890.19
ST-400-0340-0508-0655	4 mm	34 mm	26 mm	50.81 mm	19.33	Phosphor Bronze (QSn4-0.3)	12.4	966.5
ST-080-0092-0132-0632	0.8 mm	9.22 mm	7.62 mm	13.19 mm	0.17	Oil-Tempered Spring Wire (SWO)	16.1	24.71
ST-500-0485-0995-0698	5 mm	48.48 mm	38.48 mm	99.48 mm	44.615	Oil-Tempered Spring Wire (SWO)	18.1	3270.25
ST-250-0195-0197-0662	2.5 mm	19.52 mm	14.52 mm	19.72 mm	18.348	Inconel X-750	7.3	669.7
ST-120-0151-0210-0605	1.2 mm	15.08 mm	12.68 mm	21.05 mm	0.318	Beryllium Copper (QBe2)	16.4	41.46
ST-200-0185-0155-0705	2 mm	18.48 mm	14.48 mm	15.5 mm	7.37	Carbon Spring Steel Wire (SWC)	7.4	353.05

Rate: N-mm/degree; maximum load: N-mm. Dimensions are in millimeters.

Engineering Data

Typical Dimensions & Design Data

Use these data points to compare geometry, material and working parameters when defining your custom spring. Final values are reviewed and confirmed for the actual assembly before production.

Configuration	Data type	Key parameters	Material / basis
Engineering Data 01	Engineering Data	Construction: Standard Straight-Leg Torsion Spring Data use: Engineering reference	Round/flat/profile wire as applicable
Engineering Data 02	Manufacturing Range	Wire diameter minimum: 0.1 mm Wire diameter maximum: 65 mm Type: Torsion spring / torsion bar family	Carbon / stainless / alloy spring materials
Engineering Data 03	Design Input	Key field 1: Torque @ angle Key field 2: Leg geometry Key field 3: Shaft / body diameter	Per application
Typical Configuration 04Data point	Typical Configuration	Wire diameter: 3.6 mm Inside diameter: 12.4 mm Outside diameter: 19.6 mm Maximum torque: 4777.41 N·mm Coils / turns: 5.75 Reference parameter: 91.8733 N·mm/deg	Stainless steel
Typical Configuration 05Data point	Typical Configuration	Wire diameter: 2.7 mm Inside diameter: 16.1 mm Outside diameter: 21.5 mm Maximum torque: 2373 N·mm Coils / turns: 5.25 Reference parameter: 26.3667 N·mm/deg	Stainless steel
Typical Configuration 06Data point	Typical Configuration	Wire diameter: 2.4 mm Inside diameter: 18.7 mm Outside diameter: 23.5 mm Maximum torque: 1808 N·mm Coils / turns: 12.75 Reference parameter: 6.6963 N·mm/deg	Stainless steel

Design note: dimensions, force / torque, material, tolerances, fatigue life and compliance are finalized against your drawing and operating conditions during quotation.

Next Design Decisions

Next Steps for Your Spring Design

Once the spring style is selected, confirm how it works in the assembly, which material suits the environment, how it will be manufactured and which dimensions and performance points should be controlled on the drawing.

Applications

Where this spring style fits

Review best-fit uses, assembly constraints and situations where another spring style may be a better choice.

View application guidance →

Materials

Choose the material for the environment

Music wire and alloy spring steels suit many compact high-cycle torsion designs; stainless and specialty alloys are selected when the pivot area is exposed to corrosion or heat.

Compare spring materials →

Manufacturing

Plan prototype and production

Review forming, heat treatment, secondary operations, inspection and the path from first samples to repeat production.

View manufacturing capabilities →

Engineering Data

Open matching engineering guides

Matching material and wire-diameter pages provide additional design data for material and size selection.

Open Spring Engineering Guide →

Material Direction

Common Material Families to Review

The links below are selection guides, not a claim that every grade is suitable for every size or load.

Carbon & Alloy Spring SteelsSelection guide Copper Alloy Spring MaterialsSelection guide Nickel & High-Temperature Spring AlloysSelection guide Stainless Steel Spring MaterialsSelection guide

Engineering Support

Spring Engineering Guides

Use these guides to compare material, wire diameter and standard requirements before finalizing the product drawing.

Material data Phosphor Bronze (QSn4-0.3) Torsion Springs Engineering Data 9 matching straight-leg torsion springs data rows are included in the category. Material data Inconel X-750 Torsion Springs Engineering Data 7 matching straight-leg torsion springs data rows are included in the category. Material data Carbon Spring Steel Wire (SWC) Torsion Springs Engineering Data 7 matching straight-leg torsion springs data rows are included in the category. Wire diameter 0.3 mm Torsion Springs Engineering Data 3 matching straight-leg torsion springs data rows are included in the category. Wire diameter 0.8 mm Torsion Springs Engineering Data 3 matching straight-leg torsion springs data rows are included in the category. Wire diameter 2 mm Torsion Springs Engineering Data 6 matching straight-leg torsion springs data rows are included in the category.

Compare Designs

Use these alternatives when the available space, connection style, travel or force direction changes.

Product Questions

Straight-Leg Torsion Springs FAQ

Why does leg length matter if torque is specified?

Torque is the rotational output, but the linear force at the leg contact point equals torque divided by the contact radius. Moving the contact point changes that force.

Should a torsion spring fit tightly on the shaft?

No. Some clearance is normally required so the coil can wind without binding. The exact allowance depends on geometry and working angle.

RFQ

Send the Working Requirement

A drawing is ideal. If you do not have one yet, provide the dimensions, load or torque, travel, environment and expected quantity that matter in the assembly.

CustomSprings Engineering Catalog

Request This Spring

Send your dimensions, quantity and drawing for engineering review.

Request a Custom Quote

Fields marked * are required. A drawing is recommended for accurate review.

Spring Requirements

Spring Type Wire / Thickness (mm) Outside Diameter / Envelope (mm) Inside Diameter / Bore (mm) Free Length / Height (mm) Spring Rate / Torque Load / Torque Coils / Turns / Leaves Quantity * Material Finish Drawing PDF, CAD, image or ZIP; maximum 10 MB.

Contact Information

Company Contact Name * Email * Phone / WhatsApp Country / Region Application

Notes