Eco-friendly invisible car film is a thermoplastic urethane, often self-healing film that is applied to the painted surfaces of a new or used car to protect the paintwork from stones, scratches, crushed insects, and minor damage. It is able to effectively resist natural oxidation caused by prolonged exposure to atmospheric conditions as well as protect the car from scratches and sand.

Recently, one owner of a BMW 3 Series wanted to apply a protective film onto his car but could not find any suitable product on the market. This prompted him to have the invisible film custom-made.

Film for protecting paintwork is divided into two categories: cut on plotters using PC files prepared in advance and cut by hand. The differences between them are as follows: for computer-cut films, the cutting process precedes gluing and is carried out in accordance with the data of the car prototype, with the fitting process requiring high accuracy; installation of hand-cut film is carried out in reverse order.

The biggest advantage of computer cutting is its safety. The hand-made option inevitably involves cutting over the paintwork and removing parts (for example, logo, door handles). During the process, the paintwork can get scratched, while computer cutting is relatively safe.

In addition, computer-cut films, which are delivered as finished products, can significantly reduce raw material costs and operator skill requirements, thereby increasing operational efficiency.

Despite the obvious advantages of computer-cut films, they often impose extremely high data requirements on prototype vehicles — meeting production needs can only be achieved through the availability of large, constantly updated databases. Thus, such films are not suitable for vehicles with non-standard body kits, discrepancies with the factory version, etc.

Difficulties in making protective films

A typical process for cutting film for a car on plotters includes the following steps: 3D scanning of the entire car, obtaining a 3D model → processing a 3D model, developing a curved surface, preparing files → cutting a film → gluing a film. This process places extremely high demands on the accuracy of the data so that the paint protection film adheres tightly to the vehicle with clean edges and correct dimensions. For this purpose, a handheld 3D scanner seems to be the perfect solution.

The main obstacles to obtaining vehicle data are the large measurement area and numerous complex curved surfaces. A handheld 3D scanner boasts the advantages of easy operation, non-contact scanning, high accuracy, and high scanning speed, which allows the device to meet the needs of getting proper vehicle body data.

ScanTech 3D solution

ScanTech offers a few series of products, including KSCAN, AXE, and HSCAN/PRINCE handheld 3D scanners. They all use markers to perform highly accurate scan positioning. In particular, the KSCAN and AXE scanners feature large scan areas, ultra-fast speeds (about 30 seconds for a car door scan), and an integrated photogrammetry system with a volumetric accuracy of 0.030 mm/m to ensure the accuracy of vehicle data.

When it comes to making a paint protection film, ScanTech offers portable and tracking 3D solutions.

Method 1

The PRINCE handheld 3D scanner offers two scanning modes: red and blue laser scanning, which combine the flexibility and efficiency of portable 3D scanners with high detail resolution of up to 0.030 mm. Thus, the PRINCE perfectly meets the requirements for acquiring 3D data of a car body. Positioning and stitching are carried out online using magnetic and self-adhesive markers that can be automatically applied to the car body.

Curves are drawn according to the scanned data to obtain the drawing used for cutting the film in production.

The prototype drawing is transferred to the film cutting device in order to obtain the corresponding shapes.

Method 2

Another option perfectly suited for this purpose is the ScanTech TrackScan-P42 3D scanner that can track the position of the device to perform marker-free scanning, which can greatly improve work efficiency and reduce labor and material costs.

According to the requirements of various scanning scenarios, the TrackScan-P42 can switch between several modes.

Drawing of a paintwork protective film prototype:

Applications of 3D scanning are certainly not limited to car paintwork protective films. 3D scanners are widely used for reverse engineering, geometry inspection, and visualization in a variety of industries.

Creating databases using 3D-scanning