The adoption of additive manufacturing methods is becoming prevalent in industry. Socio-economic trends seek more customization and sustainability in production. An increase in unique service components will warrant the need for more flexible repair methods. This is particularly important for components that are difficult to access or disassemble — thus requiring an on-site repair. This paper introduces the use of 3D printing pens as a means to perform repair to additively manufacturing components. A study was conducted to assess the feasibility of using a 3D printing pen in maintenance, repair and overhaul (MRO) applications on polymer-based service products. A series of tensile tests were conducted on printed specimens, pre- and post-repair, to examine the tensile retention of the mended region. Results indicate significant retention in tensile strength in the mended specimens, supporting the notion of the pens relevance in repair and overhaul applications. Specimens that fractured within the repair region were seen to have retained (81 ± 10) % of their original tensile strength while specimens that fractured outside the region retained (86 ± 4) %. Considering the limited control of the study, results acquired encourage further analysis of the underlying mechanisms in the process, with the intent to more efficiently exploit this approach for practical structure-based repair applications.