Introduction: Faculty members have little time and usually lack expertise to provide writing feedback on lab reports. Sending students to a writing center, an existing resource on virtually all college campuses, could fill that gap. However, the majority of peer writing tutors are in nontechnical majors, and little research exists on training them to provide support for engineering students. Research question: Can peer writing tutors without technical backgrounds be trained to provide effective feedback to engineering students? About the case: Previously, sending students to the writing center was ineffective. The students did not see the value, and the tutors did not feel capable of providing feedback to them. To remedy this situation, an interdisciplinary training method was developed collaboratively by an engineering professor and the writing center director. Situating the case: Researchers have suggested that effective writing center help for engineering students is possible, and the authors have designed an interdisciplinary training method that has produced positive results. Supporting literature includes the use of generalist tutors, writing in the disciplines, genre theory, and knowledge transfer. Methods/approach: This was a three-year experiential project conducted in a junior-level engineering course. The assignment, a lab report, remained the same. Qualitative and quantitative data were collected from students and tutors. Results/discussion: Tutor feedback and student satisfaction significantly improved. However, a few students who were satisfied overall still expressed interest in having their reports reviewed by a tutor with a technical background. Conclusions: Interdisciplinary tutor training can improve the feedback of peer writing tutors, providing support for faculty efforts to improve student writing. The method requires minimal faculty time and capitalizes on existing resources.