Manufacturers have to adapt very quickly to the accelerating world and use specialized machines for production to meet the demands. This also means that those machines are not used as often as their mass-producing counterparts and sometimes become obsolete. In the case of foaming with injection molding, a complicated system has to be built around the machine and has to be structured in a specific way, which is not always cost-efficient. In this paper, two methods of chemical foaming of Acrylonitrile Butadiene Styrene (ABS) were performed on a regular injection molding machine. Chemical Blowing Agent (CBA) and Expandable Microsphere (EMS) were used with breathing mold technology. Injection molding parameters were modified, and specimens were produced for mechanical and morphological examinations. Properly selected parameters for foaming play an important role in retaining the mechanical strength of the product. With low switch-over volume and using the core-back method, it is possible to foam ABS using a Chemical Blowing Agent.