Not every early-stage prototype needs to be metal, and for plastic 3D printing the choice usually comes down to SLA or SLS — two processes that look similar on a quote line but produce very different parts. Picking the wrong one for a given stage of development is one of the more common, and avoidable, ways a prototype iteration gets wasted.

SLA: the process for how a part looks and fits

Stereolithography cures liquid resin with a laser, layer by layer, producing the smoothest surface finish and finest visual detail of any process Lab Ready runs. It's the right call for early form studies, master patterns, and any part where a stakeholder — a surgeon, a regulatory reviewer, an internal design review — needs to see and hold something that looks like the final device before functional testing starts.

SLS: the process for how a part performs

Selective Laser Sintering fuses nylon powder without support structures, which means it can produce complex, interlocking or hollow geometry SLA can't. The tradeoff is a grainier surface finish than SLA — but nylon SLS parts are genuinely functional: they can be snap-fit, drop-tested and handled roughly during a fit check without the fragility of a resin part. That makes SLS the better choice once a design has moved past “does this look right” into “does this work.”

When neither plastic process is the answer

Once a prototype needs to hold up under a real load case, or the application calls for a specific alloy for biocompatibility, plastic additive gives way to metal — see DMLS vs SLM for how that decision gets made. The full process list, including CNC machining and injection molding for parts headed toward production volume, is on the Capabilities page.

If it's not clear yet which stage a design is at, that's a normal starting point for a quote — send the CAD file and what the part needs to prove, and process selection is part of the review.