3D Printers: Common Types of Technologies



When you are searching for a used 3D printer for sale, you’ll notice a number of types of technologies with different names. To help you compare similar types of printers, below are five common technologies with their synonyms and similar technologies as you may find advertised on a used 3D printer for sale.

Fused Deposition Modeling



Similar Technologies/Names: (Fused deposition modeling (FDM)), fused filament fabrication, plastic jet printing, filament extrusion, fused filament deposition, and material deposition.

Fused deposition modeling is the most widely used form of 3D printing with models available at the consumer level as well as the industrial level. This technology builds parts layer-by-layer from the bottom up. It heats and extrudes a thermoplastic filament. Thermoplastics are available with special properties like toughness, translucence, biocompatibility, electrostatic dissipation, UV resistance, and high-heat deflection. The relative weakness of this technology is that you may have visible layer lines and the parts are weaker along the layer lines. Larger FDM machines require compressed air for high-performance plastics.

PolyJet Technology



Similar Technologies/Names: (PolyJet technology), multi-jet printing, photopolymer jetting

PolyJet 3D printers work similarly to a traditional inkjet printer, but instead of jetting ink onto paper, the print head jets liquid photopolymers onto a build tray. Each droplet is cured in a flash of UV light. This type of 3D printer can provide sharp precision, smooth surfaces, and very fine details. It can mix photopolymers in specific concentrations to many materials, even rubber, and human tissue. 3D printers with photopolymer jetting make amazing realism with a full gamut of colors.

Stereolithography (SL)



Similar Technologies/Names: (stereolithography), SLA, vat photopolymerization

A 3D printer with stereolithography (SL) technology is an excellent option for very tight tolerances and smooth surfaces. A UV laser cures and solidifies very fine layers of photopolymer in an open vat with this technology. Designers like this technology for quick build times for strong parts made of transparent, heat-resistant, moisture resistant materials. A relative weakness of this technology is UV sensitivity (parts are often painted for this reason) and extra post-curing steps. 3D printers of this type required dedicated manufacturing space with ventilation and a specialty multi-stage alcohol treatment.

Laser Sintering (LS)



Similar Technologies/Names: (laser sintering), selective laser sintering, SLS, power bed fusion

If you are looking for a 3D printer capable of building parts with good mechanical properties and extremely complex geometries like undercuts, thin walls or interior features, then finding a laser sintering 3D printer for sale might be your best bet. A laser sintering 3D printer uses a high-powered CO2 laser to melt and fuse powdered thermoplastics selectively. Parts made with this technology can be watertight, airtight and flame retardant since materials can hold excellent isotropic properties – equally strong in all directions.

Metal Powder Bed Fusion (MPBF)



Similar Technologies/Names: (metal powder bed fusion), selective laser melting, metal laser melting, direct metal laser melting

MPBF is a type of 3D printing that makes it possible to produce complex geometries not possible with conventional metal manufacturing processes. It uses a precise high-wattage fiber laser that micro-welds powdered metals and alloys to form components similar to wrought counterparts. Strong and durable parts can be made with additive metals like Inconel, aluminum, stainless steel, and titanium. It’s possible to make features like internal cavities, thin walls, undercuts and interlocking components which are difficult or impossible to make with machining. Usually, this selective laser melting 3D printing is used for prototypes, low-volume runs, or for parts that cannot be cast or machined.