What Is 3D Printing?
3D printing builds a physical object from a digital file by stacking thin layers of material. Another name for it is additive manufacturing, since the machine adds material rather than cutting it away. In occupational therapy, it is used to make custom tools, adaptive equipment, assistive devices, prototypes, and replacement parts.
A Brief History of 3D Printing
3D printing began as a factory tool for building prototypes faster than machining or molding. As desktop machines dropped in price and slicing software got simpler, the technology moved into schools, libraries, clinics, maker spaces, and small shops. Today it is used in healthcare, education, engineering, product design, and assistive technology.
How 3D Printing Works
Every print starts with a 3D model. You download it from an online library, build it in CAD software, or edit an existing design. The model goes into slicing software, which cuts it into horizontal layers and writes the toolpath the printer follows. In the slicer, you set orientation, layer height, infill density, support placement, material type, and print speed. The finished file goes to the printer, which lays down one layer at a time until the part is complete. The Print Process page walks through each step.
FDM Printing
FDM is the most common desktop method. The letters stand for fused deposition modeling. The printer pulls a solid plastic filament, melts it through a heated nozzle, and deposits the molten line layer by layer. Common filaments are PLA, PETG, and ABS. FDM machines cost less and require fewer steps than other printers, so students, clinics, libraries, and makerspaces tend to own them. All of the devices and examples this website covers are designed for FDM printing.
Resin Printing
Resin printing swaps filament for liquid photopolymer that hardens under UV light. The process captures fine detail and leaves smooth surfaces, which suit small models and parts with sharp features. Resin parts need more handling after the print finishes. Each one comes out wet, is washed in isopropyl alcohol, and then cured under a UV lamp. Uncured resin and the alcohol wash are irritants, so the process requires gloves and good ventilation. Those added steps make resin printing a harder starting point than FDM printing.
Other Types of 3D Printing
Industrial and medical shops use other methods. Some melt nylon or metal powder with a laser. Others bind specialized powders into solid parts. These machines can produce strong, precise components, and they cost far more than a desktop printer. For a first printer, FDM is the practical choice because the hardware and filament are easy to find and use.
Why 3D Printing Can Be Useful in OT
In OT, a printed device can be shaped to fit the person who will use it. A grip might be sized to a hand, a handle thickened for a weak grasp, or a tool angled to match a patient’s limited range of motion. When a commercial product does not fit the task, the model can be edited and a new version printed. Depending on the size of the object, each iteration usually costs a few cents in materials and a few hours of print time, rather than purchasing a new item.
Important Reminder
A printer does not replace clinical reasoning, safety checks, or professional judgment. This page is educational only. Nothing here represents a design or device as safe, durable, effective, or cleared by any regulator. Before a printed device is used, a qualified individual should evaluate its fit, material, durability, and infection-control needs and decide whether it suits the person and setting. A printed part can fail, fit poorly, irritate skin, or create choking or sharp-edge hazards, so check all prints closely. Using anything described here is at your own risk; for the full terms, see the Legal Disclaimer and Terms of Service.