CNC Bending
CNC bending forms sheet and plate on computer-controlled press brakes with a programmable back gauge, giving repeatable bend angles and flange dimensions on every part. It is used for brackets, enclosures, channels and any bent sheet metal component.
What it is
The CNC controls ram depth and back-gauge position for each bend, so multi-bend parts are formed in sequence with consistent angles. Programs are stored for repeat orders.
Tooling (punch and die) is selected for material thickness and inside radius, typically with a die opening around 6–10 times the thickness.
Typical applications
- Brackets and angles
- Enclosure and cabinet panels
- Channels, U-sections and Z-sections
- Chassis and trays
- Architectural and furniture parts
Suitable materials
- CRCA and HR mild steel
- Galvanised steel (GI/GP)
- Stainless steel (304, 316)
- Aluminium (5052, 6061)
Points to consider
- Minimum flange length is roughly 4× thickness plus the radius, depending on tooling.
- Inside bend radius is usually about equal to thickness for mild steel; harder materials need larger radii.
- Bending across the grain reduces cracking risk on harder materials.
- Dimension bent parts to outside or inside consistently.
Frequently asked questions
What is the difference between CNC bending and press brake bending?
CNC bending is press brake bending with computer control of stroke and back gauge, giving better repeatability on multi-bend parts.
What is the minimum flange length?
Roughly four times the material thickness plus the bend radius, though it depends on the tooling available.
Why do bent parts crack?
Usually a radius too tight for the material, or bending parallel to the rolling direction. A larger radius or bending across the grain helps.