PolyJet 3D printing is the technology we reach for when a prototype has to look and feel like the finished product: crisp detail, smooth surfaces, rigid and rubber-like materials in one part, and in some cases full color. At eCadCam, our Glendale studio has been producing prototypes and models for Los Angeles designers, engineers, and studios for more than 22 years, and PolyJet is one of the most requested processes for realistic, presentation-quality parts. Here is how it works, what it does well, and when another 3D printing process is the better call.
How PolyJet 3D Printing Works
PolyJet is a material-jetting process. Instead of extruding plastic like FDM or curing a vat of resin with a laser like SLA, a PolyJet printer jets microscopic droplets of liquid photopolymer onto a build tray and cures each layer instantly with UV light. Because layers are extremely thin, parts come out with fine detail and very smooth surfaces straight off the machine.
The key difference is that the print head can deposit more than one material in the same job. That is what makes multi-material, multi-hardness, and multi-color parts possible without assembling separate pieces afterward.
What Makes PolyJet Different From Other 3D Printing Technologies
Multi-material and multi-hardness parts
A single PolyJet part can combine rigid and flexible materials. Think of a handheld device prototype with a hard housing and a soft-touch rubber-like grip, or a seal and its mating part printed together. Digital material blending also lets us vary stiffness across a part, which is hard to replicate with other processes.
Full-color and transparent options
PolyJet can print in color, which is valuable for packaging mockups, medical and anatomical models, architectural presentations, and design reviews where color communicates information. Clear materials are also available for lenses, light pipes, and see-through housings, although transparent parts usually benefit from finishing to reach their best clarity.
Fine detail and smooth surfaces
Thin walls, small text, and intricate features generally reproduce well in PolyJet, and the surface finish is typically smoother than FDM or SLS. That cuts down on the sanding and filling needed before painting or presenting a part.
Best Uses for PolyJet Prototypes
- Looks-like prototypes: investor and client presentations, trade-show samples, and design approval models.
- Overmolded and soft-touch concepts: grips, gaskets, buttons, and wearables that mix rigid and flexible materials.
- Medical and anatomical models: color-coded models for planning, teaching, and device demonstrations.
- Packaging and consumer product mockups: realistic color and finish before committing to tooling.
- Fit checks for assemblies: detailed small parts that need to mate accurately.
Limitations to Know Before You Choose PolyJet
PolyJet photopolymers are generally not the right choice for functional parts that must withstand heat, sustained load, or long-term sunlight. Many PolyJet materials are more brittle or can change over time compared with engineering thermoplastics, so they are best viewed as excellent prototype and model materials rather than end-use production plastics.
Cost is another factor. PolyJet material is more expensive than FDM filament or SLS nylon, so it tends to make sense for smaller, high-value, appearance-critical parts. For large or strictly functional parts, other technologies usually offer better value. If you are weighing your options, our guide to choosing between FDM, SLA, and SLS and our article on MJF nylon parts are good places to compare.
How to Prepare a File for PolyJet Printing
A few habits make PolyJet jobs go smoothly and keep costs predictable:
- Send a watertight STL, OBJ, or 3MF file; for color parts, use a format that carries color or texture information.
- Tell us which areas should be rigid, flexible, clear, or colored, and which surfaces are most visible.
- Avoid features that are unsupported or too delicate to survive support removal. PolyJet uses a removable support material, so we will review overhangs and trapped cavities with you.
- Share the purpose of the part. A presentation model and a fit-check part are often printed and finished differently.
If you are not sure your model is ready, we can review it first. Our walkthrough on preparing a 3D model for printing covers the basics.
PolyJet 3D Printing in Los Angeles
Whether you need a single realistic concept model or a small run of detailed prototypes, we can recommend the right process for your goals, budget, and deadline, and finish parts to the level you need. PolyJet is only one of the technologies we offer, so you get an honest recommendation rather than a one-size-fits-all answer.
Ready to see your design in realistic detail? Request a quote from eCadCam in Los Angeles, or call us at 213.489.1173. Send your files and a short description of the part, and we will help you choose the best process.