August 18, 2026
Designing wire form structures for CNC
Bend radius, minimum legs, springback, and datums for 4–14 mm structures. What to put on the print so the first article is the part.
A pretty solid in CAD is not a wire structure. The CNC follows a centerline. If the model is a tube with a mesh texture, we will ask for a DXF of the pitch and a section of the rim. Design for the process or pay for the translation.
Radius and legs
Inside radius should be at least 1× diameter unless you like tool marks and a conversation about cracking. Minimum straight between bends is what the bender needs to grip — starve it and the angle walks. Stainless springback is not 1018 springback. 330 is its own animal. Put the inside radius on the print, not “make it like the carbon version in stainless.”
Datums that matter
Hole-to-hole, mount-to-mount, overall that hits a fixture. Not every leg ±0.005. Structures stack error through weld shrinkage. Inspect the interfaces. A peel sample on the mesh. Overlay on the frame.
Stock diameters save tooling
3/8, 7/16, and 1/2 in are on the floor. Other sizes in 4–14 mm run, with a program and often a coil buy. Changing diameter to hit a theoretical weight is how a simple structure grows a tooling line. Design guide is the longer version of this post.