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Forming · Press brake

Sheet metal bending

CNC press-brake bending in steel, stainless and aluminum, with bend-allowance worked out from your material and tooling so the flat pattern is right the first time.

Bending is where a flat blank becomes a part, and it is also where most fabrication problems start: a wrong bend allowance throws every downstream dimension off, and a flange that is too short simply cannot be formed. We treat bending as a planned operation — material, grain direction, inside radius and bend sequence are decided before the blank is cut, not on the shop floor.

Capabilities at a glance

ParameterRange
Max bend length4,000 mm
Max tonnage320 t (heavier on request)
Material thickness0.5 – 12 mm (steel) · 0.5 – 8 mm (aluminum)
Angle tolerance±0.5°
Bend-position tolerance±0.1 – 0.2 mm
Typical inside radius≈ material thickness (V-die dependent)

How bend allowance works

When metal bends, the outer surface stretches and the inner surface compresses; somewhere between them sits the neutral axis, which keeps its length. The flat blank has to be sized to that neutral length, not to the sum of the outer dimensions — otherwise the finished part is oversized by the bend deduction at every bend. We calculate the bend allowance from the actual K-factor for your material and our die, which is why we ask for material grade and thickness up front.

What this means for your drawing

Materials we form

MaterialNotes
Mild steel (SPCC, Q235)Most economical; powder coat or zinc plate to prevent rust.
Stainless 304 / 316Springback is higher — we over-bend to compensate.
Aluminum 5052 / 60615052 forms well; 6061-T6 cracks on tight radii, so we use a larger radius or anneal.
Galvanized / pre-coatedFormable; we protect the coating with film tooling where finish matters.

Related processes

Most bent parts start as a laser-cut blank and finish with powder coating or plating. Quoting them together avoids handling charges between shops.

Frequently asked questions

What bending tolerance can you hold?

On a CNC press brake we hold a typical angle tolerance of ±0.5° and a bend-position tolerance of about ±0.1–0.2 mm. Accumulated tolerance grows with the number of bends, so we flag stack-up on multi-bend parts during DFM review.

What is the minimum flange length you can bend?

As a rule of thumb the minimum flange is about 4x material thickness plus the inside bend radius. Shorter flanges need a special tool or a different sequence, which we will note on the quote.

Do I need to add bend reliefs to my drawing?

For bends near an edge, a bend relief prevents tearing and distortion. If your DXF does not include them we add them in DFM and confirm with you before cutting.

Can you match an existing part without a drawing?

Yes. Send a sample or a photo with key dimensions over WhatsApp and we can reverse-engineer a flat pattern and bend sequence for low-to-mid volumes.

Need a quote on sheet metal bending?

Send your drawing or sample specs — we reply with price, lead time, and DFM notes the same day.