mini8 Great question! In our experience, the substrate plays a big role in the final durability.
For smooth or non-porous materials like glass, metal, acrylic, and tiles, surface preparation is very important. We usually recommend cleaning the surface carefully and using a suitable primer or coating to improve ink adhesion.
For painted walls, it depends more on the wall condition, paint quality, and whether the surface is dusty, rough, damp, or peeling. A clean, stable, and dry surface will usually give much better results.
For outdoor UV printing, we normally suggest using primer when adhesion may be an issue, and adding protective varnish when the project will face strong sunlight, rain, high humidity, frequent cleaning, or abrasion. For simple indoor or low-contact applications, it may not always be necessary.
The safest approach is always to test a small area first, especially when working with a new material. 😃
