There are two ways to get a perforated part, and they come off two different machines.
Stock perforated sheet is produced on a roll-fed press, which stamps a standard pattern across the full width of the coil and sells it by the sheet. It is built for volume and uniformity.
A custom punched part is produced on a CNC punch press, where the program places the perforation, the cut-outs, the mounting holes, the formed features and the outer profile into your part, in one setup.
When stock sheet is the right call
Buy the sheet when the part is a simple rectangle, the pattern is uniform across the whole face, nothing folds near the perforation and the area is large. For 40 square metres of a standard pattern, stock sheet wins on price and it is not close.
What custom punching gives you
The pattern goes exactly where the drawing puts it. Solid margins at the bends, fixings and welds, a dense field where the airflow is needed, and a clean edge all round. The pattern can change across a single panel: open in one area, solid in another, graduated in between.
Faster turnaround. One program, one setup. No buying sheet, no second cutting operation, no waiting on a supplier before the job can start.
Lower cost per finished part. Stock sheet is cheaper per square metre, but the price does not include cutting the blank to shape, the offcut you pay for and discard, or the extra handling. Counted per finished part, punching is usually the better buy.
A finished component off the machine. It goes straight to folding, welding or finishing.
Where it suits
Ventilation panels and enclosure doors, machine guards and covers, generator and compressor housings, architectural screens and cladding, balustrade infill, shelving and trays, kiosks and cabinetry, food service equipment, filter and acoustic panels.
A worked example
A 900 × 600 mm ventilation panel, 1.6 mm zinc-coated steel, four mounting holes, a 25 mm return flange all round, 30% open area, quantity 20.
Punched, it is one program: the field sits inside a 30 mm solid margin, the mounting holes go in during the same setup, the profile is cut and the blank goes straight to the folder. One machine, one handling step, twenty identical panels.
FAQs
Is custom perforation more expensive than buying perforated sheet?
Per square metre, yes. Per finished part, usually not, because the punched part arrives cut to shape with the pattern placed to the drawing and no offcut to pay for.
Can you perforate a part that also needs folding?
Yes. The program places the pattern clear of the bend lines, so the fold happens in solid material.
What materials can you perforate?
Mild steel, stainless steel, aluminium, zinc-coated and ZINCALUME® steel, brass and copper.
Send us your drawing
We’ll tell you which way gives you the better price on the finished part. See our punching and forming capability, the full sheet metal punching guide, or perforation patterns and open area for how we set a pattern. Get a quote.
