Shearing

Shearing cuts sheet metal to size with straight-line blade action, delivering fast, low-cost blanks but limited to simple edges and moderate tolerances.

Overview

Shearing (guillotine cutting) slices sheet metal between upper and lower blades to make straight cuts across a full width. It’s one of the fastest ways to produce rectangular blanks and trim edges, with minimal heat input and high throughput on a shear or power squaring shear.

Choose shearing for high-volume or repeatable straight cuts where edge cosmetics are secondary and features don’t require internal cutouts. It works well as a first step to create blanks that will later be punched, formed, or laser cut.

Tradeoffs: geometry is limited to straight lines (no holes, slots, or curves), and edge quality depends on material, thickness, and blade condition—expect rollover, burnish, and fracture zones plus a burr that may need deburring. Accuracy is good for blanking but typically looser than laser on small parts, and distortion/camber can occur on thin or high-strength sheets if not supported properly.

Common Materials

  • Mild steel
  • Stainless steel 304
  • Aluminum 5052
  • Aluminum 6061
  • Galvanized steel
  • Copper

Tolerances

±0.010" to ±0.020"

Applications

  • Rectangular sheet blanks for press brake forming
  • Cabinet and enclosure panels cut to size
  • Shim and spacer stock cut from sheet
  • Strip stock for progressive dies
  • Trim cuts on welded sheet assemblies
  • Plate and sheet edge trimming before secondary ops

When to Choose Shearing

Pick shearing when the part can be defined by straight cut lines and you need fast, low-cost blanking from sheet in moderate to high volumes. It fits well for pre-cut blanks feeding forming, punching, or secondary machining. Expect to plan for burr direction and potential deburring if edges are functional or customer-facing.

vs Laser Cutting (CO2)

Choose shearing when the job is primarily straight cuts on larger blanks and cycle time and cost per cut matter more than complex profiles. Shearing avoids heat effects and is typically faster for long, straight edges, especially when nesting isn’t needed.

vs Laser Cutting (Fiber)

Choose shearing for simple rectangular blanks or strip stock where you don’t need fine features or tight profile tolerances. A shear can outpace laser on straight-line throughput and reduces programming and nesting effort for commodity blanks.

vs Plasma Cutting

Choose shearing when you need cleaner edges and better dimensional consistency on thin-to-medium sheet and when heat distortion must be minimized. Shearing is also typically faster and cheaper for straight cuts, while plasma is better suited to thicker plate and irregular profiles.

vs Waterjet Cutting

Choose shearing when parts are straight-edged blanks and you want the lowest cut cost and highest throughput. Waterjet wins for complex shapes and thick materials, but it’s slower and usually overkill for simple guillotine cuts.

Design Considerations

  • Call out sheet thickness, alloy/temper, and grain direction if it matters for forming after shearing
  • Specify which edges are functional and require deburring; otherwise allow standard shear burr
  • Avoid very narrow strips or small blank sizes that are hard to hold down; ask the shop for minimum safe part width
  • Add generous handling clearance for later ops; sheared blanks often need squaring/edge cleanup before precision features
  • Define blank size tolerance separately from overall finished-part tolerance if secondary ops will locate off other datums
  • If flatness matters, note allowable camber/warp and discuss support/hold-down to prevent distortion on thin sheet