Automotive Plastic Repair

Key Points

• Introduction to plastics in car design: Since the late 1960s, starting with the Pontiac Endura's plastic-coated, steel-frame bumper, there has been a significant increase in the use of both nonstructural and structural reinforced plastics in various areas of car bodies. Reinforced plastics are used for their strength and stability, while unreinforced plastics are found in parts like door trim and body molding.
• Auto body plastic repair products: With the emergence of plastic auto body parts, specific repair products have been developed. Technicians use identifiers to determine the type of polymer used in a part, such as PP (polypropylene) and ABS (acrylonitrile butadiene styrene), as determined by the International Standards Organization (ISO) guidelines. This identification is crucial for selecting the appropriate repair methods, especially when dealing with polymer blends.
• Cosmetic vs. two-sided repairs: Repair techniques vary depending on the damage. Cosmetic repairs address surface issues, while two-sided repairs are needed for more severe damage, like tears or holes. The repair process also differs between reinforced and nonreinforced plastics, involving methods like grinding and heating to address damage.
• Post-repair refinishing and career path: After repairs, parts usually undergo a refinishing process to match the rest of the vehicle, a task often performed by refinish technicians. These technicians work closely with collision repair technicians to ensure a seamless restoration. For those interested in this field, programs like the Collision Repair & Refinish Technology (CRRT) program at Universal Technical Institute (UTI) offer training, covering topics from identifying plastics to applying various repair technologies.¹

Plastics have been used in car design since the late 1960s, when a plastic-coated, steel-frame bumper made an appearance on the Pontiac Endura. Since then, there has been increased use of nonstructural and structural reinforced plastics in many different areas of car bodies.

When strength and stability are needed, plastics are mixed with additional fibers. Unreinforced plastics are typically used in places like door trim and body molding.

Regardless of the type of plastic being used and where it’s located, these parts will likely need repair or replacement when a vehicle is involved in an accident. There’s a lot that goes into automotive plastic repair — keep reading to find out more!

Auto Body Plastic Repair Products

With the development of plastic auto body parts, repair products were also designed to be used specifically with the material.

When determining what plastic repair products to use, collision repair technicians typically locate an “identifier” that lets them know what type of polymer was used in the manufacturing of the part. This is typically found via an abbreviation, which can include:

• PP: Polypropylene
• PO: Polyolefin
• ABS: Acrylonitrile butadiene styrene
• PC: Polycarbonate
• PE: Polyethylene
• PVC: Polyvinylchloride

These are designated by the International Standards Organization (ISO) and are used globally to assist with plastics recycling. Sometimes, polymer blends are used to manufacture parts, and in this case, the markings would reflect all plastics used.

How To Fix Plastic Car Body Parts

Plastic repair products are helpful for collision repair shops, since they help cut the amount of time it takes to fix a part. Instead of having to order a new part, a collision repair technician can use these products to make a fix without waiting. Using these products is also more cost-effective for customers.

Before beginning the repair, technicians need to determine what the plastic is made from and if it’s fiber-reinforced for the best chance of success. It also helps them know what car plastic repair methods to follow.

Most repairs are categorized as either cosmetic or two-sided.

Cosmetic repair vs. two-sided repair

Cosmetic damage refers to a scratch or minor dent on the plastic car body part, while two-sided damage goes completely through the surface of the part as a tear or hole.

Repair adhesives can be used for both cosmetic repairs and two-sided repairs. Plastic welding is also a common technique used by technicians. This process occurs when plastic surfaces are pressed before being exposed to heat and pressure, which allows them to create a molecular bond and join together.

How To Perform Automotive Plastic Repair

The right training is needed to know how to repair plastic car body parts using different products and methods. Collision repair technicians are careful to follow the standard operating procedures that come with the different supplies they use.

Precision and skill are important when it comes to repairing plastic parts. Auto body techs know to take their time and focus on getting the job done right the first time.

One of the most important things to consider when repairing plastics is the need to maintain cleanliness during the process. Steps are taken to ensure plastic parts are cleaned before starting the repair process using specialized cleaning products that remove waxes, dirt and road oils. Compressed air can also be used.

Technicians will also ensure they know what plastic is used in a part to see if it is reinforced or nonreinforced.

Common fiber-reinforced plastic parts include hoods and fenders. These fibers can change the density of the part and the repair method being used. Often, the area that is damaged is ground to relieve stress placed on the plastic.

In nonreinforced plastics, heat is sometimes applied to soften the plastic, and the damage is then pushed out.

After completing an automotive plastic repair

Once a repair has been made on a part, the parts typically go through a refinishing process that helps them match the rest of the vehicle.

A common career path collision repair technicians can take is that of a refinish technician. These techs prepare and apply paint to the repaired parts of vehicles. They mix colors, sand, tint and seal so the repaired area can better blend in with the vehicle’s existing finish.

Collision repair technicians and refinish technicians work together to ensure vehicles are restored properly. Refinish technicians have training and knowledge about what can be used on specific plastics as well to ensure the process goes smoothly!

FAQs

What are automotive plastic repair challenges?

Matching the original texture and color of the vehicle while ensuring durability and longevity is typically the most challenging part of automotive plastic repair. The advanced driver assistance systems (ADAS) sensors on modern vehicles also present challenges. An improper repair can interfere with ADAS sensors, reducing overall safety.

Is automotive interior plastic repair for a deep scratch possible?  

Yes! Repair techs often use heat tools to make the damaged area more pliable. They then level the surface with the appropriate filler and use texturing tools to restore the original pattern. Finally, they'll complete any necessary finishing and color matching.

What are the differences between professional car plastic repair and DIY methods?

Professionals follow ISO guidelines and have access to the advanced tools and specialized materials needed for a seamless, durable finish. If you have a high-value vehicle with modern technology like ADAS sensors, visiting a trained technician is the best route.

DIY methods are more cost-effective and accessible but not as durable. Various car plastic repair kits can help, but these kits are only effective for minor damage, and the finish may not match the rest of the vehicle.

Learn Automotive Plastic Repair Techniques at UTI

Does making repairs to different plastic parts on a vehicle sound interesting to you? If you enjoy working with your hands and have strong attention to detail, a career in collision repair could be a good fit!

The Collision Repair & Refinish Technology (CRRT) program at Universal Technical Institute (UTI) can train you in a variety of methods for making repairs to vehicles damaged in accidents. The program, which takes 51 to 54 weeks to complete, could give you the hands-on training necessary to pursue a role in the field.¹

Courses cover several topics, including “Exterior Panel Repair I” which teaches students how to identify different automotive plastics and make repairs using different adhesive and welding technologies.

Ready to get started? Request more information to get in touch with an Admissions Representative today!

UTI Campuses That Offer Collision Repair Training

• Long Beach, California
• Houston, Texas