Deformation is one challenge CNC machinists encounter when working with POM. Below are the four main courses of deformation and their solutions.
Cutting Heat
POM material has low thermal stability, is heat-sensitive, and is quickly distorted due to inadequate cooling after manufacturing. To combat this heat, you should make:
The tool has to be sharp so that the heat produced when cutting is minimal;
The quantity of cutting may be decreased, divided into many cuts;
Increase the quantity of cooling liquid.
The goal is to minimize the formation of heat or quickly remove the heat produced during the cutting operation.
Internal Stress
Engineering plastics have a high thermal coefficient of expansion, thus when there is a considerable machining allowance, deformation will result from removing internal tension. To combat this:
Choose and prepare materials properly;
Utilize symmetrical POM processing to counteract the stress and deformation brought on by processing when the quantity of material removal is quite high;
Regulate the margin, and attempt to insert as thick of a material as you can.
Clamping
When the POM material is clamped, it will distort, and once released, it will revert to its previous shape. One way to combat this is to enhance the workpiece’s contact surface by:
Modify the clamping form. For instance, the bench vise cushions items and fixes them with glue;
Vacuum suction cups may be employed for bigger plates, but a flat blank is required;
Use suction cups to secure the smoothed surface after using adhesive to fix one side and then sweeping it.
Elasticity
The elasticity of the POM material is rather great. Due to the material’s elasticity, the component in touch with the tool will flex internally during cutting. The portion that has been cut and pressed will experience a little distortion once the tool has been removed. It is now required to make several tool-compensating changes per the cutting impact. Cutting repeatedly while processing a small amount of material helps lessen the dimensional distortion brought on by the material’s elasticity.
