Vacuum Chuck Fixture Plate 6061 Aluminum Sealed Vacuum Grooves 0.01mm Flatness

Dongguan Changxinda Precision Technology Co., Ltd. has machined custom parts to drawing since 2008. The plant runs 4-axis and 5-axis machining centers, turn-mill combined lathes and precision CNC lathes, employs more than 90 people, and exports 50 to 60 percent of output to industrial buyers in Europe, North America and Southeast Asia. ISO 9001:2015 certified, first article reports with ballooned drawings as standard.

A vacuum chuck fixture plate holds a part by air pressure instead of clamps. The top face carries a network of grooves, the workpiece covers them, and a pump pulls the volume between the grooves and the part down to a partial vacuum. The result is uniform clamping across the whole footprint, no clamp marks on the finished surface, and access to five sides of the part in one setup. This page covers the groove design, the sealing and the flatness that make it work.

Groove Geometry And Seal Design

The groove pattern decides how much force the plate can generate and whether the part stays put during a heavy cut.

• Concentric rings: the standard pattern for round and square parts, with a cross groove connecting the rings so the vacuum reaches the whole area even if one ring is partly outside the workpiece.
• Grid pattern: used when the plate serves many different part sizes, with plugged ports to isolate unused zones.
• Groove width and depth: 2 mm to 4 mm wide and 1.5 mm to 3 mm deep, sized so the groove volume does not exceed the pump capacity, and the groove does not collapse under the part load.
• Seal groove: a dedicated O-ring groove around the perimeter for parts that need a hard stop, or a flat land for gasket tape on general purpose plates.
• Vacuum ports: drilled and tapped from the side or the bottom, with a filter element so chips never reach the pump.

Flatness Is The Whole Function

Leakage scales with the gap between the part and the plate, so a plate that is out of flat by 0.05 mm will hold a flexible part poorly no matter how large the pump is.

• Top face flatness 0.01 mm over plates up to 300 mm, 0.02 mm above that, measured on a granite plate with a grid of points
• Parallelism between the top face and the machine table face held to 0.01 mm, so the plate does not need shimming on the machine
• Stress relieved before finishing, since hogging out the groove network releases stress in the plate
• Grooves cut after the face is finished, using a light finishing pass so the groove edges do not raise a burr above the sealing surface
• Vacuum integrity tested by capping the ports and measuring the decay rate over five minutes

Anodizing, Sealing And Surface Treatment

• Hard anodizing on the working face for wear resistance, with the groove edges masked so coating build up does not close the groove
• Sealing faces left uncoated or lightly coated, because a coated face changes the gap and the leak rate
• Bead blasted finish on non functional areas for appearance and for grip when the plate is handled with oily hands
• Stainless steel plates for cleanroom and medical fixture use, with electropolishing available
• Laser marked zone numbers and part size references on the plate edge, so operators pick the right port

Custom Plate Configurations

• Plate sizes from 100 x 100 mm to 600 x 400 mm, thickness from 15 mm for plates that must resist pump load without bowing
• Materials: 6061-T6 and 7075-T6 aluminum, 304 and 316L stainless, with aluminum as the default for weight
• Multiple vacuum zones with individual ports for large plates that carry several small parts at once
• Integrated locating pins, dowel holes and edge stops to position the workpiece without a separate fixture
• Mounting pattern to your machine table T-slots, with counterbored holes and a reference edge
• Plates supplied with the matching pump fittings, hose and filter, ready to connect

Delivery And Support

• Single plates: 7 to 12 working days including anodizing and vacuum test
• Small batches of 10 to 50 plates: 12 to 20 working days
• Each plate ships with a flatness report, a vacuum decay test record and the groove layout drawing
• Replacement O-rings, gasket tape and fittings supplied as spares with the first order
• Application review before quoting: part size, material, cut load and pump capacity are checked against the groove design

Questions From Fixture Engineers

How much clamping force can a vacuum plate generate?

Roughly one kilogram per square centimetre at a full vacuum, so a part covering 200 square centimetres sees about 200 kilograms. That is ample for finishing cuts and light roughing, and it is why the plate is normally used with a mechanical stop for heavy cuts.

Will a vacuum plate hold a thin part without distorting it?

Yes, and that is its main advantage over clamps. The load is spread over the whole footprint instead of concentrated at a few points, so a 1.5 mm plate stays flat while it is being faced.

Can the plate be re-machined after years of use?

Yes. The top face can be skimmed and the grooves re-cut to restore flatness, and we keep the groove program on file so the refurbishment matches the original.