Process
Heavy wire forming, 4–14 mm
4–14 mm (0.157–0.551 in). 3D CNC and secondary work for frames, wire baskets, guards, and routing forms — not music-wire clips.
The 4–14 mm band
Wire forming as a trade runs from hair-thin spring wire to rod that behaves like bar. Most “CNC wire forming” pages quote 0.020–0.375 in and then stop. This library is the other side of that line.
| Diameter | Inch | Typical work |
|---|---|---|
| 4 mm | 0.157 in | Display, appliance, lighter frames, 3D hooks |
| 6–8 mm | 0.236–0.315 in | Seat frames, racks, guards, wire-basket stock |
| 10–12 mm | 0.394–0.472 in | Heavy frames, material handling, furnace fixtures |
| 14 mm | 0.551 in | Structural wire, heavy wire baskets, rod-frame work |
4 mm is already past most fourslide and light AIM cells. 14 mm is past a typical BLM 12 mm head. The process still looks like CNC wire forming — straighten, feed, rotate, bend, cut — but the machine, the straightener, the cutoff, and the print rules all change.
Why diameter comes first
A 1 mm clip and a 12 mm wire-basket frame are not the same trade. Springback, min radius, tool occupancy, and weld heat all scale with section. We quote 4–14 mm because that is the cell: which head, which pin, which alloy, which fixture.
Below 4 mm is light CNC, fourslide, and spring work. Above 14 mm is bar and fabrication. We will say so rather than stretch the brochure.
What can actually bend 4–14 mm
- 4–8 mm — production 3D CNC (AIM / IP Automation class, Numalliance, BLM) if tensile and radius fit the head.
- 8–12 mm — heavy 3D CNC. Brochure max is not the same as a tight 3D path in stainless. Confirm the head, not the PDF.
- 12–14 mm — the top of industrial wire CNC. Some European heads stop at 12 mm. 14 mm often wants the heaviest 3D cell or a press / fixture assist on the worst bends.
Benchtop benders (Pensa and similar) and Arduino builds are not in this band. Neither is a light spring former. See 3D CNC wire forming for the machine map.
Design rules that change at this diameter
The design guide still applies. The numbers get large:
- Inside radius — start at 1× diameter on mild carbon (14 mm wire → 14 mm IR). Stainless and high-tensile: closer to 1.5–2×. A “sharp” CAD corner at 12 mm is a crack, not a bend.
- Min leg — 2–3× diameter is 28–42 mm of straight between bends at 14 mm. Tight zigzags that work at 2 mm do not translate.
- Straightening — coil set energy is high. A weak straightener prints banana into every span.
- Cutoff — a real shear or saw, not a light bushing nick. End deformation has to be called out if the end is a weld or a hole entry.
- Weld — frames and wire baskets in this band are often formed + welded, not a single closed CNC path. Leave a gap or a joint on the print.
- Tolerance — ±0.5 mm on a 400 mm span is a different conversation than ±0.005 in on a clip. Fixture the interfaces.
What 4–14 mm parts actually are
- Seat frames, headrest and lock rods, visor skeletons — automotive
- Machine guards, frames, and handles
- Wire baskets, racks, carts, and display wire
- Heat-treat and furnace fixtures (rod frame, often 330 / nickel)
- HVAC and material-handling forms
- Heavy hooks, loops, and routing that has to carry load
- S-hooks, D-rings, J-hooks, and cable hangers
If the function is a stored-energy coil with a rate, that is a spring shop — usually well under 4 mm. If the function is a shape in heavy wire, it belongs here.
Outside the band
Below 4 mm: light CNC, fourslide, and spring cells. This site will still explain those processes so the map is complete, but production quotes start at 4 mm.
Above 14 mm: bar, tube, and fabrication. Different machines, different prints. We will say so rather than stretch the brochure.