Shot Peened SLS Parts
Shot peening for SLS 3D printed PA12 nylon smooths the surface, removes residual powder, and delivers a satin, professional sheen. The process enhances dyed black parts by producing a darker, more consistent color and a premium look that feels closer to molded plastics. At this time, shot peening is only offered on dyed black PA12 nylon parts with white shot peening planned for the future.
What is Shot Peening?
Shot Peened SLS Parts
Shot peening transforms the surface of SLS nylon into a smoother, satin finish that feels closer to molded plastics. The process uses high energy polymer media to lightly strike the part’s surface, removing powder residue and creating a subtle sheen. The result is a premium finish that looks refined and feels more professional in the hand.
Our Shot Peening Process
We perform most shot peening in house using dedicated blasting equipment. For larger parts and high volume production, we also work with our trusted partner DyeMansion in Austin, TX, to maintain consistency at scale. At this time, shot peening is only offered on dyed black parts, since white nylon can discolor slightly during the manual process. In the future, we may expand to offer white shot peening as well.
Appearance and Finish
- Satin Sheen: A semigloss surface that reflects light more evenly than the natural granular texture on SLS PA12 Nylon.
- Cleaner Surfaces: Residual powder is almost completely removed, leaving parts with a crisp, professional feel.
- Sharper Features: Because the process is less abrasive than polishing, details and edges remain well defined.
- Consistent Black Finish: Dyed parts look darker and more uniform after shot peening, reducing the variation seen in raw finishes.
- Imperfections May Stand Out: While smoother, the finish can make layer lines or minor surface variations slightly more visible.
Benefits of Shot Peening
- End Use Ready: Produces parts with a premium look and feel suitable for customer facing applications.
- Cost Effective Upgrade: Adds visual and tactile quality at a lower cost than vapor smoothing.
- Feature Friendly: Less aggressive than polishing, so thinner models and delicate details survive better.
- Powder Removal: Provides an additional cleaning stage that leaves parts with minimal residue.
- Efficient Turnaround: Faster to produce than vapor smoothing, making it a practical upgrade for production runs.
Shot Peened Expectations
Media Retention
The polymer media used in shot peening is small enough to become lodged in tight grooves, narrow channels, or deep cavities. Designs that do not meet our minimum guidelines may retain some media, especially in enclosed features.
Fragile Features
Although shot peening is gentler than other finishing methods, thin walls and delicate geometries can still break under impact. Designs with more robust proportions are better suited for this finish.
Bosses and Posts
Slender posts or protrusions remain vulnerable during peening. Adding fillets or reinforcement at the base can improve strength, but does not fully eliminate the risk of breakage.
Sharp or Trailing Edges
Edges that taper to a fine point are highly prone to chipping or damage. We do not recommend edges thinner than 1 mm for any finish, and such features are not covered for reprints if damaged.
Small Parts
Parts under 10 mm are more difficult to handle and can be misplaced during finishing. For these, we may use sinterboxes or cages to keep them secure, though customers should be aware of the added risk.
Surface Consistency
Shot peening improves overall appearance, but the smoother finish can also highlight layer lines or small imperfections in the print. While cosmetic only, these details may be more noticeable on darker dyed parts.