3D printing on textiles using Fused Filament Fabrication (FFF) enables the creation of hybrid materials with unique functional and aesthetic properties. However, the soft, elastic, and insulating nature of textiles presents significant challenges for achieving stable adhesion and reproducible print quality. This paper introduces a novel mechanical fixture – the Precise Adjustable Hoop Mount (PAHM) – designed to securely and reproducibly hold textile substrates in place on the printer bed, while allowing for fine height adjustment to accommodate various fabric thicknesses. The PAHM is compatible with standard embroidery hoops and can be mounted on the Prusa XL without modifying the printer hardware. To further enhance process reliability, a custom G-code start sequence was developed to accommodate the physical presence of the hoop and avoid collisions during initialisation. The approach also supports Mesh Bed Leveling (MBL) either directly on the bed for accuracy or on the textile surface for faster setup. Additionally, a hybrid physical-digital method was implemented to map a collision-free print area, ensuring safe and optimised use of the build volume. Together, these developments significantly improve the repeatability, adhesion quality, and user-friendliness of 3D printing directly onto textiles, paving the way for future applications in smart textiles, wearable technology, and personalised manufacturing.