There are a number of factors—resolution, tolerance, material selection, surface finish—to consider when designing for the industrial 3D printing process of stereolithography (SL). For our latest tip, we’ll discuss the four SL finishing options available at Proto Labs, and when it makes sense to use each.
SL technology uses a build platform that requires support structures for all features so they don’t float away or collapse during the build process. These support structures are removed after the build is complete, but they do leave visible markings on the part.
In an unfinished state, after the support structures are removed, dots or nibs are noticeable where structures were attached to the part surfaces. So, when would leaving a part unfinished make the most sense?
- When a clear part is desired with no custom finishing
- If you have your own finishing capabilities, or have another shop that can perform post-build finishing
- To achieve the best accuracy possible
A natural finish provides a surface finish that absent of dots or nibs, which leaves a more desirable cosmetic appearance. The surface is not as clear on the down-facing surfaces that had supporting structures, but the top surface would remain clear. When should you use a natural finish?
- On small or delicate features that may be destroyed by additional finishing such as grit blasting
- On clear parts where down-facing surfaces are not a cosmetic concern