Technologies
A CNC press brake is a computer-controlled sheet metal bending machine that uses a precision punch and die set to apply controlled force along a programmed bend line. It achieves repeatable bend angle
A CNC press brake is a computer-controlled sheet metal bending machine that uses a precision punch and die set to apply controlled force along a programmed bend line. It achieves repeatable bend angles — typically within ±0.5° — across mild steel, stainless steel, and aluminium sheets from 0.5 mm to
A CNC press brake is a computer-controlled sheet metal bending machine that uses a precision punch and die set to apply controlled force along a programmed bend line. It achieves repeatable bend angles — typically within ±0.5° — across mild steel, stainless steel, and aluminium sheets from 0.5 mm to 12 mm thickness. The CNC controller automates bend sequence, back-gauge positioning, and ram depth, eliminating manual setup variation and enabling production runs of identical parts with positional accuracy consistent with ISO 2768-m tolerances.
For engineers in Cairo, Alexandria, Jeddah, Riyadh, and Dammam sourcing precision brackets and enclosures, this automation eliminates costly rework and delivery delays. Our CNC machining services in Egypt complement press brake work for complete part fabrication.
Three bending methods dominate industrial press brake work, each with distinct accuracy profiles and tooling requirements. Air bending leaves a small air gap between the sheet and die cavity, allowing the punch to stop mid-stroke. This method tolerates material thickness variation and works well for multi-angle parts; accuracy is ±0.5° to ±1°, and minimum inside bend radius approximates the material thickness. Bottoming presses the sheet fully into the die, increasing contact area and repeatability to ±0.25°–±0.5°; this method suits high-volume runs where consistent angles matter. Coining applies maximum tonnage, forcing material fully into the die shape and eliminating spring-back entirely, achieving ±0.1°–±0.25° — the precision choice for critical parts, though tooling and tonnage costs rise. Wipe bending, a fourth variant, rolls the sheet over a rounded die edge for flanges and edge profiles.
| Bending Method | How It Works | Typical Angle Accuracy | Best For | Minimum Inside Radius |
|---|---|---|---|---|
| Air Bending | Punch stops before full die contact; material spring-back compensated by overbend | ±0.5° – ±1° | Complex multi-angle parts, thin sheet, cost control | ~1× material thickness |
| Bottom Bending | Punch presses sheet fully into die cavity | ±0.25° – ±0.5° | High repeatability, medium thickness, production runs | ~0.75× material thickness |
| Coining | Full tonnage forces material into die with zero spring-back | ±0.1° – ±0.25° | Precision parts, tight angular tolerance, critical assemblies | ~0.5× material thickness |
| Wipe Bending | Sheet wiped over rounded die edge | ±1° | Flanges, edge profiles, thin material | Depends on die edge radius |
At Entag, air bending handles the majority of sheet metal work — it balances cost and accuracy for engineering-grade brackets, panels, and structural frames across mild steel (S235, S355), stainless steel (304, 316), and aluminium (5052, 6061) up to 12 mm thickness. Bottoming is specified when angular repeatability is critical; coining is reserved for precision medical device enclosures and high-end industrial assemblies where tolerance stack-up is non-negotiable. Our sheet metal fabrication in Egypt integrates bending with other processes for complete solutions.
What is the maximum thickness of sheet metal a CNC press brake can bend?
CNC press brake capacity depends on machine tonnage and material grade. At Entag, we bend sheets from 0.5 mm to 12 mm across mild steel, stainless steel, and aluminium. Thicker material (10–12 mm) requires higher tonnage and larger bend radii. For custom thickness requirements above 12 mm, contact our team for tooling feasibility assessment.
What tolerances should I specify for press brake bending?
Specify ±0.5° for angular tolerance on standard air bending jobs; this aligns with CNC press brake repeatability and reduces tooling cost. For tighter control, request ±0.25° (bottoming method) or ±0.1° (coining), though these incur higher setup charges. Positional tolerances along the bend line follow ISO 2768-m medium-grade standards.
Do I need to include bend allowance in my CAD file?
No. Entag's engineers calculate bend allowance automatically from material grade and thickness. Provide a flat-pattern drawing with finished bend angles and inside bend radii clearly marked. If you supply a 3D bent model, we flatten it and verify against your intended final dimensions before production.
What is the difference between air bending and bottom bending?
Air bending stops the punch before die contact, leaving an air gap; it tolerates material variation and suits complex shapes (±0.5° accuracy). Bottoming presses the sheet fully into the die for higher repeatability (±0.25°) and is best for production runs requiring consistent angles across identical parts.
Can CNC press brake bending handle stainless steel and aluminium?
Yes. Stainless steel (304, 316) bends cleanly with slightly higher tonnage and dies designed to resist galling; inside bend radius should be ≥1× material thickness to avoid cracking. Aluminium (5052, 6061) is highly bendable but requires careful spring-back calculation — we compensate automatically using material-specific lookup tables.
What file format should I submit for a press brake bending quote?
Submit DXF (flat-pattern) or STEP (3D model). DXF is preferred; include bend lines, finished dimensions, material grade, sheet thickness, and any surface finish or edge prep requirements in the drawing notes. Entag processes quotes within 24 hours of CAD upload.
Ready to start your project? Request a quote on Entag — upload your CAD file and get a price in 24 hours. We deliver CNC press brake bending across Egypt and Saudi Arabia with ±0.5° angular accuracy and ISO 2768-m positional tolerances. Explore our tube fabrication services and 3D printing services in Egypt to see how bending integrates with complementary manufacturing processes for complete part production.
