## 2 Materials and Methods
For example, if an object is scanned using a laser-based scanning system, reflections from the transparent material can create interference that leads to inaccurate data. Similarly, if an object is scanned using a photogrammetry-based system, shadows created by the transparent material can result in missing or incomplete data. To overcome these challenges, there are several techniques and technologies that can be used when scanning transparent materials. One approach is to use specialized scanning systems that are designed to work with transparent materials. These systems may use specialized lighting, cameras, or sensors that can mitigate the effects of refraction, reflection, or shadows. Another approach is to apply a coating or spray to the surface of the transparent material that can help to reduce reflections and refraction. This can help to improve the accuracy of the scanned data and reduce the likelihood of errors and measurement problems. In summary, scanning transparent materials for 3D printing can be challenging due to the optical properties of the materials. However, by using specialized scanning systems or applying coatings or sprays, it is possible to improve the accuracy of the scanned data and reduce errors and measurement problems in the final 3D-printed object. Regarding 3D printers, there are several different types of 3D printing technologies available, each of which uses a different method to deposit layers of material to create an object. The most common types of 3D printing include Fused Deposition Modeling (FDM), Stereolithography (SLA), and Selective Laser Sintering (SLS) [34]. Fused Deposition Modeling (FDM) is the most prevalent 3D printing technique. It works by heating a filament of plastic or other material and extruding it through a nozzle to build up layers of material to create an object. FDM printers are relatively inexpensive and easy to use, making them a popular choice for home and hobby use. FDM technology works by depositing layers of material that are melted and hardened as it is printed. This process is widely used to create prototypes, manufacturing tools, and complex parts. It is a relatively inexpensive and accessible 3D printing technology that is used in industries such as manufacturing, aerospace, automotive, and medical. FDM technology is reliable, accurate, and easy to use, making it a popular choice for businesses and hobbyists alike. FDM printers are available in a wide range of sizes and materials, so they can be used to meet a variety of needs. One of the advantages of FDM 3D printing is that the material used is recyclable and can be used multiple times. FDM technology is also more precise than other 3D printing technologies, allowing for the creation of complex and precise parts [44; 45]. Another advantage of FDM technology is that it can be used to construct very large objects with dimensions in meters. This is possible because FDM printers can be designed with a large build volume, allowing them to create objects of considerable size. Additionally, FDM technology is relatively low-cost compared with other manufacturing methods used to produce large objects, making it an attractive option for industries that require large-scale fabrication. While FDM is an affordable and accessible technology, the surface of objects produced by FDM can sometimes appear rough or uneven. Fortunately, there are several methods available to improve the surface quality of FDM printed models. One method is to use chemical treatments to smooth out the surface of the printed model. Acetone is a commonly used chemical that can be applied to the surface of models made from materials such as ABS or PLA. The acetone vapors dissolve the outer layer of the model, smoothing out any visible lines or imperfections on the surface. Another chemical treatment involves using a mixture of isopropyl alcohol and water, which can have a similar smoothing effect. Thermal treatment is another method used to improve the surface of FDM printed models.