Several clamping methods for grinding on surface grinders

2025-08-27 15:12:54

Common thin parts such as washers, friction plates, templates, and thin plates suffer from poor rigidity, poor heat dissipation, and bending after heat treatment. This leads to deformation during clamping and warping during grinding. These parts are typically ground using magnetic chucks on surface grinders. Once grinding is complete, the magnetic attraction is removed and the thin workpiece returns to its original shape, making it difficult to ensure machining accuracy. The following clamping methods can be used to ensure that the thin workpiece is positioned and clamped in a free state, and double-end grinding can be performed to achieve good results and meet the required machining accuracy.

Clamping method of elastic gasket

When grinding thin workpieces like these on a surface grinder, an elastic clamping mechanism is used to position and clamp the workpiece while it's free. A 0.5mm thick layer of rubber is placed between the workpiece and the magnetic table. When the workpiece is subjected to magnetic attraction, the rubber is compressed, minimizing its elastic deformation, thereby grinding out a flat surface. Repeated grinding cycles can achieve the required precision.

Strengthening the rigidity of thin sheet workpieces with temporary measures

Using epoxy resin bonding agent, the thin sheet workpiece is bonded to a flat plate in a free state. Place the tablet and sheet together on the magnetic suction cup. After grinding the flat surface of one end of the thin sheet, remove the thin sheet workpiece from the flat plate, place the ground surface on the magnetic suction cup, and then grind the flat surface of the other end of the thin sheet workpiece. Due to the fluidity of epoxy resin before hardening, it can fill the gap between thin sheet workpieces and flat plates. After the epoxy resin hardens, the workpiece is bonded to the flat plate as a whole, greatly enhancing the rigidity of the workpiece. Under magnetic attraction, thin sheet workpieces will not undergo clamping deformation, creating conditions for grinding flat surfaces. Thick grease can also be used instead of epoxy resin to fill the gap between the thin sheet workpiece and the magnetic suction cup, enhancing the rigidity of the workpiece and achieving good results.

Mechanical clamping method

Use the flat-nose pliers included in the surface grinder's accessories to hold the thin workpiece against the magnetic worktable. Because the flat-nose pliers are at a certain height, the magnetic force on the jaws is small. Grind one surface of the thin workpiece flat by gradually reducing the feed rate, then remove it. Place the ground surface back on the magnetic worktable and grind the other surface of the thin workpiece. Repeat this process several times until the flatness of both surfaces meets the required level.

Vacuum clamping method

This method utilizes atmospheric pressure to clamp thin workpieces for grinding. The working principle is as follows: A rubber sealing ring is placed on the clamping body, creating a sealed chamber between the workpiece and the clamping body. A vacuum pump is then used to evacuate the air from the vents, clamping the workpiece. Due to the low clamping force, circular grinding can be used. After grinding the flat surface of one end of a thin workpiece, the same method can be used to grind the other end, achieving satisfactory results.