4 Common Local Electroplating Process Methods for CNC Parts

In production, some CNC parts are often plated locally, such as only the inner diameter surface; some are only plated on one end, while the rest are plated with other coatings; some are only plated on one side, while other CNC parts are not allowed. Coated, etc. In order to achieve the purpose of local electroplating, the following methods can be used.

Partial electroplating and process method thereof

Generally, electroplating can be divided into two types: full plating and partial plating according to the plating area. Many CNC parts that need local electroplating need to be insulated and protected for their non-plated surfaces. This requires different local insulation methods to meet the technical requirements of construction to ensure that the non-plated surfaces of the CNC parts will not be plated, especially if there are special requirements CNC parts.

According to daily work experience, several local electroplating process methods commonly used in electroplating are introduced.

Wax Protection Act

The characteristics of insulating wax preparations are that they have good adhesion with CNC parts, a wide range of operating temperatures, and the end edge of the insulating layer will not lift up. Therefore, it is suitable for CNC parts with high dimensional tolerances and complex shapes of insulating end edges. In addition, the wax preparation can also be reused with little loss, but its use method is more complicated and the cycle is long. When applying the wax preparation, the CNC parts should be preheated to 50~70°C, and then the melted wax preparation should be applied. First, apply a thin layer to cover the entire surface to be insulated. At this time, the wax should not solidify halfway, and then apply again and again. to the desired thickness. After coating, in a warm state before cooling to room temperature, trim the edge of the insulation with a knife, and then wipe the surface to be plated repeatedly with a cotton ball dipped in gasoline. This operation should be very careful. After plating, the wax preparation can be melted and recovered in hot water or a special wax bucket, and then the CNC parts can be cleaned with a solvent such as gasoline or a water-soluble cleaning agent.
 

special fixture method

The special fixture method is also called the profiling fixture method. That is to say, for some CNC parts with complex shapes, a special insulating fixture can be designed according to the shape of the CNC parts, which can greatly improve the production efficiency. For example, when the inner diameter or outer diameter of the bearing is partially chrome-plated, a special bearing chrome-plating fixture can be designed, and this fixture can also be used repeatedly.

bandage

This method uses tape or plastic strips, tape and other materials to insulate and protect non-coated surfaces. The packaging method depends on the shape of the part. The present invention is suitable for simple CNC parts, especially circular CNC parts with regular shapes. Bandaging is the simplest method of insulation protection.

Toxic paint

Add 10% sulfide to ordinary insulating paint and coat it on the CNC parts that need to be insulated. When the CNC parts are activated and electroless plated, due to the catalytic toxicity of this poisoning paint, the coating CNC parts cannot be chemically plated. The plating process plays a role of local insulation.