Plastic Part Surface Finishing & Post-Processing Service

TDL supports rapid prototyping, tool making, plastic injection molding, injection molded parts surface finishing and post-processing for OEM manufacturing customers.

plastic molded part surface finishing plastic painting

TDL help customers do surface finishing for plastic parts like electroplating, plastic painting, silk printing, laser engraving, PVD coating, vacuum plating, chrome plating, nickel plating, gold plating, tin plating, zinc plating, silver plating, pad printing, etc.

The surface treatment for mechanical CNC machined parts like sandblasting, polishing, brushing, spraying, painting, powder coating, electroplating, anodizing, PVD coating, laser engraving, chrome plating, oil painting, etc.

For plastic parts or metal parts post-processing like ultrasonic welding, hot melt welding, trimming, drilling, bronzing, screwing, gluing, assembly, heat staking inserts, etc. 

We make plastic molds for customers and also do the plastic painting.
Let`s look at how TDL does plastic painting:
1, Polishing the surface of raw plastic parts;
2, Manual cleaning and dust removal to create a better painting surface;
3, Using an electrostatic gun or electrostatic brush to remove dust on the surface, this process operated in a clean room;
4, Painting primer. This process is critical. Most defects are caused in this step, so we should be cautious.
5, Baking primer painting, let`s become solid;
6, Polishing and cleaning for the second painting;
7, Spray UV painting for protection and a glossy appearance;
8, Baking & UV paint light curing;
9, Quality inspection;
10, Packaging.

How does TDL do chrome plating for plastic parts?
1, Plastic parts raw material/plastic parts ready;
2, IQC rechecks the parts;
3, Plastic parts hang on hangers;
4, Degreasing and washing;
5, Roughening (in dilute sulfuric acid) and washing again;
6, Palladium sink (palladium water) and cleaning the third time;
7, Chemical nickel plating and washing;
8, Coke copper plating and washing;
9, Bright copper plating and washing all the same;
10, Semi-gloss nickel plating;
11, Bright nickel plating;
12, Bright chrome plating and washing like above;
13, Drying, then doing a full inspection, and finally moving to package.

Surface Finishing

TDL supports surface finishing and post-processing for customers about plastic production OEM manufacturing.

Insert molding general process information

Plastic Part Electroplating

Plastic electroplating is to coat the plastic surface with metal, which not only increases the appearance, but also compensates for the shortcomings of plastics. A large number of plastic electroplating products are used in electronics, automobiles, household goods and other industries. Common electroplating includes chrome plating, nickel plating, zinc plating, silver plating, gold plating, etc.

Plastic Painting

Plastic painting is to make the product look more beautiful, cover up injection molding defects, increase the surface hardness of the product, feel, etc., such as rubber painting, UV painting, PU painting, luminous painting, etc.

Plastic Silk Printing

Plastic printing is a technology that transfers the ink to the surface of plastic products through the processes of plate making, ink application, pressure and other processes, such as text, pictures, photos, anti-counterfeiting, LOGO etc., and the content of the manuscript is copied in batches. Such as silk printing, offset printing, etc.

Plastic Coating

Plastic coating means a layer of coating is attached to the surface of the workpiece to form a coating film to protect, decorate and meet other functional requirements for the workpiece. Such like powder coating, PVD coating, etc.

Laser Engraving

Also called laser engraving or laser marking, it is a surface treatment process using optical principles. Similar to screen printing, laser engraving can be used to type or pattern the product surface.

CNC machined metal parts general post-processing information

Heat treatment

Heat treatment is to heat the machined metal workpiece to a suitable temperature in a certain medium, and after maintaining it at this temperature for a certain period of time, it is cooled in different medium at different speeds, by changing the surface or internal microstructure of the metal material. A process in which structures are used to control their properties. Its purpose is to change the hardness, strength, wear resistance, electrical and magnetic properties of the metal. The overall heat treatment of steel generally has four basic processes: annealing, normalizing, quenching and tempering.


Polishing refers to the use of mechanical, chemical or electrochemical action to reduce the surface roughness of the workpiece to obtain a bright and smooth surface. It is the modification of the workpiece surface by polishing tools and abrasive particles or other polishing media.


Sandblasting is powered by compressed air to form a high-speed jet beam to spray materials (copper ore, quartz sand, emery, iron sand, Hainan sand) to the surface of the workpiece to be treated at high speed. The impact of the sand flow cleans and roughens the surface of the substrate. The process of changing the outer surface or shape of a workpiece.


The surface brushed treatment of machined parts is a surface treatment method that forms lines on the surface of the workpiece by grinding the product, which has a decorative effect. According to the different lines after brushed, it can be divided into: straight line brushed, random pattern brushed, corrugated pattern brushed, swirl pattern brushed.


Anodizing is an electrolytic oxidation process in which the surface of aluminum and aluminum alloys is usually transformed into an oxide film, which has protective, decorative and other functional properties, such as surface coloring, improving Corrosion resistance, enhanced wear resistance and hardness, protection of metal surfaces, etc.

Black oxide

The black oxide process, also known as the chemical oxidation process, immerses the processed parts in an oxidizing solution for a certain period of time, so that an oxide film is formed on the surface of the parts. This layer of oxide film can appear black, purple, blue, brown and so on. The appearance of the oxide film has a certain decorative effect, and the oxidation process has a certain anti-corrosion performance.


Spraying is a coating method that is dispersed into uniform and fine droplets by means of pressure or centrifugal force through a spray gun or disc atomizer and applied to the surface of the object to be coated. The spraying operation has high production efficiency and is suitable for industrial automation production. The application scope is mainly in the fields of hardware, plastics, furniture, military industry, ships and so on. Powder coating is popular in automotive industry.

Rolling process

Rolling processing is a kind of plastic processing method in which a high hardness and smooth roller is rolled into contact with the metal surface, and the surface layer undergoes a small amount of plastic deformation to improve the surface roughness.


Electroplating is the process of plating a thin layer of other metals or alloys on certain metal surfaces using the principle of electrolysis. So as to prevent metal oxidation (such as rust), improve wear resistance, electrical conductivity, reflectivity, corrosion resistance (copper sulfate, etc.) and enhance aesthetics.


The electrophoresis process is divided into anodic electrophoresis and cathodic electrophoresis. A process in which paint particles are deposited on the surface of a workpiece under the action of an electric field.


Etching, also known as photochemical etching, refers to the removal of the protective film in the area to be etched after exposure to plate making and development, and contact with chemical solutions during etching to achieve the effect of dissolution and corrosion, forming concave-convex or hollow molding effects.

PVD coating

Physical Vapor Deposition refers to the use of low-voltage, high-current arc discharge technology under vacuum conditions, using gas discharge to evaporate the target and ionize both the evaporated material and the gas, and use the acceleration of the electric field to make the evaporated material and its gas. The reaction products are deposited on the workpiece.
PVD technology is widely used in aerospace, electronics, optics, machinery, construction, light industry, metallurgy, materials and other fields. A film with properties such as conductivity.

Laser engraving

Laser engraving is a process of surface treatment using optical principles. The high-intensity focused laser beam emitted by the laser is at the focal point, the material is oxidized, and it is processed to show the desired etched graphics and text.



TDL’s efficient work team can help customers quickly complete product design, prototypes making, plastic mold manufacturing, injection molding production, plastic product surface finishing and assembly.

We help plastic product OEM manufacturing customers enter the market quickly and gain more market share and profits. As a one-stop tool supplier, we will be more beneficial for OEM manufacturers.

Get instant quote for your plastic products OEM manufacturing project

TDL have rich experience in innovative products and consumer electronics manufacturing, we know how to help customers to cut cost in plastic tool making.


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TDL has a lot of plastic product manufacturing experience, as a mold manufacturer, we are more trustworthy.

Injection Molding Applications

From functional prototypes to full production runs, plastic injection molding’s key industrial applications include:

Automotive products

Plastic injection molding are ideal for automotive products production, such as IMD injection molding, 2k injection molding, overmolding parts are widely used for automotive trim, sunroof plastic parts, fuel system plastics, lamp housing, and etc.

Medical Laboratory products

Various products in medical industry are manufactured by injection molding. Such as medical device, medical disposables, laboratory tips and tubes, laboratory instruments, and etc are huge demand. Plastic injection molding is good for high-volume production.

Aerospace products

Plastic injection molding manufacture wear-resistant parts, transmission structural parts, turbines, gears, bearings, impellers, blades, screws, high-pressure washers, shuttles, sleeves, bushing connectors, etc in aerospace.

Consumer-facing products

Many consumer elctronics such as TVs, stereos, headphones, digital cameras, game consoles, computers, smart phones, sweeping robot, smart security, smart wearable devices, smart tablets, smart car electronics, etc need plastic injection molding manufacturing.

Explore injection molding news and industry updates

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TDL Manufacturing Capabilities

TDL support customers with plastic mold manufacturing, Injection Molding, CNC machining, and other. Learn more about our manufacturing capabilities.