Fabrication research in HCI relies on diverse experiments to inform and assess research contributions. However, performance and reporting of these experiments is inconsistent, not only reducing transparency that reassures reviewers and readers of a project's rigour but also challenging methods’ replicability by future researchers. We analyze recent fabrication publications to extract a unified experimental workflow, which we develop into a domain-specific language, and into the openly-available Fabrication Experiment Design Tool (FEDT). FEDT facilitates designing and executing HCI fabrication experiments. We demonstrate its comprehensiveness by using FEDT to model 42 fabrication experiments from 10 papers, which leverage varied fabrication technologies and techniques, including requiring human intervention in their steps. We discuss FEDT and our modeled experiments with the papers' original authors to evaluate its precision and utility in real workflows, and we demonstrate functionality with end-to-end replications of two published experiments.