Vacuum Chucking Systems for Thin Plate & Sheet CNC Milling
Vacuum chucks utilize atmospheric air pressure differential to clamp thin aluminum plates, sheet metal, and plastic panels uniformly across their entire bottom surface with zero edge clamp interference.
Engineering Specifications & Parameters
Holding Force
Up to 1000 kg per m2 (at -0.9 bar vacuum)
Gasket Material
Cellular EPDM Rubber Cord (2-4 mm)
Vacuum Pump Type
Dry Rotary Vane or Liquid Ring Pump
Suitable Materials
Aluminum, Brass, POM, Acrylic, Carbon Fiber
Workpiece Thickness
0.5 mm to 20 mm
The Physics of Vacuum Clamping
Vacuum fixtures draw a vacuum (up to -0.9 bar) beneath the workpiece, allowing atmospheric pressure (1.01 bar approx 1 kg/cm2) to hold the sheet down uniformly.
Key Benefits
Zero Mechanical Clamp Interference: Complete unobstructed 5-sided tool access for perimeter milling and engraving.
Elimination of Thin-Wall Bowing: Vise edge clamping causes thin plates (1-5 mm) to buckle upwards in the center; vacuum holds the entire surface completely flat.
Porous Grid O-Ring Gaskets: Custom cellular rubber gaskets seal specific part contours, maintaining suction even as through-features are cut.
How do you mill through-holes on a vacuum chuck without losing suction?
Use a sacrificial porous breather mat or machine shallow vacuum channels sealed with customized perimeter O-rings around the through-cut zones.
Can warped or raw unmachined stock be held on a vacuum chuck?
Raw stock with significant bow (>0.5mm) will fail to form an airtight initial seal; stock must be reasonably flat or pressed down during initial vacuum draw.
