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Methods and techniques for bonding automotive interior textured parts


It is a good solution for parts that are too large to be built at one time, to build faster with less support material, or to build parts with finer features, to split and bond automotive interior texture parts. There are many ways and more materials that can be used to bond automotive interior textured parts. The main considerations when choosing a bonding method are the strength of the bonded joint and compatibility with each material. For intensity data, laboratory tests were conducted at the University of Texas at El Basso to measure tensile strength. Other conditions including time, cost, operational difficulty, part configuration, and general performance are also considered. However, the accuracy of automotive interior texture bonded parts depends on many factors. For example, the nature of the adhesive (such as viscosity) will affect the accuracy. Technician skills, joint styles, and fixture types have even greater impact.

To help select the bonding method that best suits your needs, the following is a brief assessment of common methods for combining parts made from a variety of materials.

Adhesive (epoxy resin)

Two-part epoxy resins are commonly used to bond parts. The epoxy resin composition is mixed and then coated by means of a spreader, a brush or an infiltration method. Automotive interior textures range in viscosity from thin caulking to thick putty, so coating techniques vary. After coating, the bond cross section is fixed or clamped during the curing of the epoxy resin.

The curing time, material properties and bond strength of various epoxy resins are different. But overall, they are easy to use. They have very good mechanical strength and usually exhibit good heat and chemical resistance. The advantage of these adhesives is that the effective time is 20 to 70 minutes, so a small adjustment can be made after the section is tight. However, the price is that the curing time is longer. When cured at room temperature, it can not be operated for many hours and the curing cycle will last for one to five days. If cured by heating, the curing process can be greatly accelerated.

Adhesive (cyanoacrylate adhesive)

Cyanoacrylate adhesives are often referred to as superglue. It is a fast curing adhesive for quick and easy repair and light duty bonding applications. Simply apply the superglue to the bonding surface and bond the sections together. Automotive interior texture adhesives cure in minutes. Super-adhesive bonded FDM parts have higher tensile strength than epoxy adhesives. However, its heat resistance, chemical resistance and solvent resistance are not good. Therefore, the use of strong adhesive bonding may reduce the performance of the part. Therefore, it is recommended to use it for conceptual models and prototypes for verifying forming and mating, not for functional prototypes or actual production parts.

Solvent bonding works by chemically dissolving the plastic to be bonded to the surface. The solvent can be applied to the cross section and then brought together and clamped, or it can be injected into a mating joint or an existing crack. Water-like dilute solvents can enter the surface gap of the part due to capillary action, which can improve the strength of repair or adhesion. Several solvents can be used, but it is recommended that the strength of the adhesive formed by this method be higher than many types of adhesives. Similar to super glue, the process is very simple and the bond site will be fixed in seconds. Another similarity is that it can be applied to areas that are difficult to reach because the solvent will reach the gap or break due to capillary action.

Its advantage over superglue and epoxy is that when the solvent is evaporated, the bonded part will contain only FDM material. Although the car interior texture bond will be fixed in a few seconds, the part should still be allowed to cure for at least eight hours. Also note that if the automotive interior textured part is heated above 176 F (80 °C), the surface may blister. Solvent welding is not suitable for chemical resistance of bonding materials and therefore has little reaction to solvents.