Pre-Plating, Post-Plating & Selective Plating: What's the Difference?

The electroplating process involves adding a metal layer to existing workpieces, which can achieve a wide range of performance advantages depending on the specific application. Various technologies and materials can be used to create unique final products, but the various choices are often daunting. We have outlined some of the main advantages of each method below.

The benefits of pre-plating

In pre-plating, raw materials are plated into continuous metal strips before any type of manufacturing process is carried out to manufacture individual parts. This means that when you cut or drill parts on the raw material strip, there will be no initial unplated coating on the sides or die-cut edges of the final part.

Pre-plating usually results in significant cost savings in terms of required labor and materials, as coating a large piece of raw material is easier than plating each finished product separately. However, if the amount of waste cut from the strip by the mold is very large, the cost of pre plating may be higher than that of post plating.

Pre-plating also reduces the risk of finished product size issues. Due to the fact that the parts do not have to roll in the barrel, their likelihood of deformation is relatively low. Compared to post plating, this is a significant advantage, as post plating often leads to dimensional issues due to increased manufacturing processes.

The metal layer added during the pre plating process provides corrosion resistance, enhanced conductivity, and a polished, smooth aesthetic.

The benefits of post electroplating

On the other hand, post plating is a function of the metal Stamping process; Due to the incomplete coating of pre plated workpieces after Stamping, post plating is usually an ideal choice for applications involving harsh environments or visible parts, therefore seamless finished surfaces are preferred.

However, post plating is usually more expensive than pre plating and requires further processing, posing a risk of dimensional issues for the workpiece. However, when it is necessary to fully cover the parts, post plating is the only option.

The benefits of selective electroplating

When two different types of coatings are required in different areas of the same part, or when only a portion of the part needs to be coated, selective roll to roll coating may be the best choice. Sometimes parts need to be plated with precious metal, but only a small portion of the parts (i.e. terminal tips) need to be plated. It is beneficial to use selective pre plating at this time. Selective pre electroplating enables us to save on raw material costs by electroplating only the parts that truly require electroplating.

Selective roll to roll electroplating is very precise and is usually used when the cost of covering the entire part with electroplating is too high. When parts require almost complete coating to prevent corrosion, it can also be used, but barrel plating can cause dimensional deformation. In this case, the part can be cut into blanks but retained on the strip. Then, they can be electroplated on the reel while still on the strip. After electroplating, the drum can be separated from the strip by passing through the printing machine once again, and the final forming can be completed to ensure dimensional control and compliance with printing specifications. A small portion of the parts called "carrier sheets" that are fixed to the strip will remain exposed, but this process allows for nearly 100% coating coverage.