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Custom Wire Form Technical Design Resources

Explore the information below to find technical advice on wire forms, including how to specify dimensions for your wire form, how to calculate the radius of a wire form, and what ranges of wire diameter can be formed.

Wire Form Dimensions

The diagram and notes describe how to specify dimensions for wire forms. We have shown our preferred ways to specify dimensions to make it easier to inspect and produce your part.

Please refer to the legend below in regards to the wire form dimensions diagram:

Bend segment drawn from edge of cut-off to theoretical corner of outside edges.
Bend segment drawn from inside theoretical corner to inside edge of perpendicular bend.
Bend segment drawn from inside edge of perpendicular bend to inside theoretical corner of inside edges.
Inside angle.
Inside diameter.
Length from edge of cut-off to center of inside diameter.
- The accumulated variation of the overall length (F) will be larger than the variation of any one dimension that makes up that overall length. A dimension like (F) that is made up of a series of bends and feed segments should be a referenced dimension. If a tolerance on an overall dimension is required, it will have to be determined after a production run.
Bend radius drawn to the inside edge of the bend.
- For low carbon (low tensile steel), we will use a bending pin with a diameter that equals 1.5X the wire diameter. So the inside radius of the bend will equal 0.75X the wire diameter.
- For harder spring tempered steel, we will use a bending pin with a diameter that equals 2X the wire diameter. So the inside radius of the bend will equal 1X the wire diameter.
Wire Diameter.

Wire Diameter Range and Wire Material Type

Wire Diameter

Specializing in building long-term partnerships with OEMs, Master Spring & Wire Form Co. has the expertise and latest equipment to manufacture the difficult or “impossible to make” wire forms. We have a wide range of CNC wire forming machines that can manufacture custom wire forms with diameters as small as 0.010″ or as large as 0.500″ (0.25mm to 12.7mm) and any size wire in between.

Wire Form Material Type

We manufacture custom wire forms from all types of material. The most common material types for wire forms are cold rolled steel (1008 or 1010 basic wire), stainless steel (type 302, type 304, type 316 or type 17-7 PH), music wire, hard drawn and oil tempered. You can learn about the suitable uses of each material type in our Properties of Materials chart.

Common Extension Spring Materials Include:

High Carbon Spring Wire
Carbon and Alloy Wire
Hard Drawn Wire
Alloy Steel Wire
Stainless Steel Wire
Non-ferrous Alloy Wire
And Many More!

Download Properties of Materials Guide

Contact Master Spring

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