2019 3D Printer Buyer's Guide | Compare Technologies

Submitted by cathryn on Fri, 08/30/2019 - 18:05

In the last decade, increased access to 3D printing technology has revolutionized the status quo in a variety of sectors, including schools , businesses, the military, and the medical field. With a number of different methods available, deciding which one to use can be a daunting and confusing process. This guide will help break down the basics on the three most commonly-used types of additive manufacturing technology: FFF, SLA, and SLS

Exhaust Header printed with FFF

A 3D Printed Exhaust Header, Created with FFF on a LulzBot TAZ Pro

Types and Descriptions:

FFF (Fused Filament Fabrication)

FFF is the most versatile, affordable, and accessible 3D printing process available, with the widest range of applications. With this method, solid thermoplastic is heated to the desired melting temperature and extruded through a nozzle. The 3D printer deposits the melted filament, which solidifies as it cools, layer-by-layer onto a build plate along predetermined coordinates until the object is completed. FFF print quality has demonstrated increasing resolution in recent years with the introduction of high-resolution tool heads. This technology is at home in every environment⁠—place it on your desk, on a cart rolled into your classroom, or on a rack inside your very own print farm.

SLA (Stereolithography)

With SLA, light-sensitive photopolymer resins are poured into a tank, containing a submerged build surface. Using an ultraviolet-tuned laser, the resin is selectively cured one layer at a time to form a solid object. Once the printing stage has completed, the next task of cleaning begins. The printer operator puts on the recommended Personal Protection Equipment (PPE) of nitrile gloves, eye-protection, and optional respirator. The uncured resin is drained from the part, the print surface is removed and the remaining resin is washed away with solvents or chemicals. The part then undergoes an additional UV curing process. While this method is favored for parts with complex geometry and small-scale objects, the cycle time and additional equipment required for build completion is more substantial relative to other methods of 3D printing.

SLS (Selective Laser Sintering)

SLS utilizes powdered synthetic polymers, which are distributed by a blade or scraper onto a build area one layer at a time. Selected portions are fused together using a high-powered laser, and the process is repeated layer by layer until the object is completed. This method primarily uses polyamides, commonly referred to as nylon, or PA for short. Support material is not necessary with this method of 3D printing, and the finished parts may have a grainy appearance with no visible layer lines.

Specifications:

	FFF	SLA	SLS
Materials	Engineering thermoplastics, including ABS, Nylons, Polycarbonate, Castables, flexible TPE's, Composite Blends, and more	Photopolymer resins	Powdered nylon blends
Layer Height Range	0.05 mm - 1.5 mm	0.025 mm - 0.15 mm	0.06 mm - 0.15 mm
Dimensional Accuracy	±200 μm	±100 μm	±300 μm
Price	Professional desktop starting at $2000, larger scale starting at $15,000	Desktop starting at $3000, larger scale from $80,000-$750,000	Desktop starting at $9000, larger scale from $10,000-$100,000
Material Price	$20-$50/kg	$50-$100/liter	$100-$500/kg
Material Consumption	One 1kg reel of filament = approximately 400 standard-sized chess pieces	One liter of resin = approximately 90 standard-sized chess pieces	Varied; dependent on machine and material
Additional Costs / Considerations	PEI build surface coating ensures proper bed adhesion when printing, rarely needing replaced when properly maintained. A few of the more expensive market options require regular changing of print bed surface. Some FFF 3D printer manufacturers charge for services, such as basic technical support and required training. Maintenance contract fees may also apply. Proprietary filament restrictions on some FFF 3D printers severely limit material options while adding significant costs.	Ultrasonic baths, which range from $300-$5000, are needed for thoroughly cleaning resin from parts Resins require post-curing in a separate unit, which can add an additional $100-$5000 Resin trays need frequent replacing, and the life span varies between 2 or 3 prints up to 20 prints depending on the type of tray and resin used. These typically cost between $20-$50 each. PEC*PAD contaminant-free wipes (for cleaning sensitive printer components) PPE (nitrile gloves, safety glasses or goggles) for handling of resins and solvents	Specialized ventilation systems Explosion proof vacuums (some dust may be combustible, requiring only a small spark to ignite) Starting at $1000 Post-processing, parts cleaning cabinet ($3000 and up), and powder recycling stations ($2,000-$12,000) are required Operation and equipment maintenance requires skilled operator High-powered lasers can be hazardous, specialized space needed PPE (nitrile gloves, safety glasses or goggles) for handling and clean-up of powder
Pros	Safe to use, non-toxic, no harsh chemicals Simple clean-up, no hazardous powders or resins Widest range of material options; print with end-use materials like ABS. Water soluble supports, multiple-color, and multiple material models can be printed with dual-extrusion 3D printers Lowest entry and material cost Easy equipment operation and maintenance Smallest physical footprint, no additional stations are required Parts can be printed quickly	Printed objects can have a smooth surface finish Printed parts are precise, with tight dimensional tolerances	No need for additional support materials Can print large number of parts simultaneously without affecting print times Strong layer adhesion
Cons	Structural strength of printed parts can be dependent on print density, orientation, and print resolution. Finest finishes requirer thinner layers and longer print times. The wide variety of material options can require filament storage space.	Resins and cleaning solvents are known to be toxic; Materials containing UV curable resins should be handled and disposed of as hazardous waste Does not print in end-use materials. Materials only emulate desired polymers. Requires a dedicated space due to unpleasant fumes and messy resins; consumables can cause contamination of nearby surfaces Multiple materials cannot be printed in a single print Additional washing and curing is required after printing Thin-walled parts are often brittle UV over- or under-exposure leads affects print durability and lifetime Build volume of desktop models is smaller in comparison to other methods Finished parts with closed structures require holes to be added for uncured resin to escape	The raw material is a powder that is hazardous if inhaled Only suitable for large, high-volume production; Small and medium single prints are not economical Grainy, sandy surface finish Materials are typically proprietary Producing large flat surfaces and small holes can be problematic, as they are susceptible to warping and over-sintering Prints are porous in nature (typically around 30%), requiring special post-processing for use in humid environments Prints require a cooling time of up to 12 hours Material escape holes must be added to designs to remove unsintered powder from hollow sections

	FFF
Materials	Engineering thermoplastics, including ABS, Nylons, Polycarbonate, Castables, flexible TPE's, Composite Blends, and more
Layer Height Range	0.05 mm - 1.5 mm
Dimensional Accuracy	±200 μm
Price	Professional desktop starting at $2000, larger scale starting at $15,000
Material Price	$20-$50/kg
Material Consumption	One 1kg reel of filament = approximately 400 standard-sized chess pieces
Additional Costs / Considerations	PEI build surface coating ensures proper bed adhesion when printing, rarely needing replaced when properly maintained. A few of the more expensive market options require regular changing of print bed surface. Some FFF 3D printer manufacturers charge for services, such as basic technical support and required training. Maintenance contract fees may also apply. Proprietary filament restrictions on some FFF 3D printers severely limit material options while adding significant costs.
Pros	Safe to use, non-toxic, no harsh chemicals Simple clean-up, no hazardous powders or resins Widest range of material options; print with end-use materials like ABS. Water soluble supports, multiple-color, and multiple material models can be printed with dual-extrusion 3D printers Lowest entry and material cost Easy equipment operation and maintenance Smallest physical footprint, no additional stations are required Parts can be printed quickly
Cons	Structural strength of printed parts can be dependent on print density, orientation, and print resolution. Finest finishes requirer thinner layers and longer print times.

	SLA
Materials	Photopolymer resins
Layer Height Range	0.05 mm - 0.15 mm
Dimensional Accuracy	±100 μm
Price	Desktop starting at $3000, larger scale from $80,000-$750,000
Material Price	$50-$100/liter
Material Consumption	One liter of resin = approximately 90 standard-sized chess pieces
Additional Costs / Considerations	Ultrasonic baths, which range from $300-$5000, are needed for thoroughly cleaning resin from parts Resins require post-curing in a separate unit, which can add an additional $100-$5000 Resin trays need frequent replacing, and the life span varies between 2 or 3 prints up to 20 prints depending on the type of tray and resin used. These typically cost between $20-$50 each. PEC*PAD contaminant-free wipes (for cleaning sensitive printer components) PPE (nitrile gloves, safety glasses or goggles) for handling of resins and solvents
Pros	Printed objects can have a smooth surface finish Printed parts are precise, with tight dimensional tolerances
Cons	Resins and cleaning solvents are known to be toxic; Materials containing UV curable resins should be handled and disposed of as hazardous waste Does not print in end-use materials. Materials only emulate desired polymers. Requires a dedicated space due to unpleasant fumes and messy resins; consumables can cause contamination of nearby surfaces Multiple colors or materials cannot be printed in a single print Additional washing and curing is required after printing Thin-walled parts are often brittle UV over- or under-exposure leads affects print durability and lifetime Build volume of desktop models is smaller in comparison to other methods Finished parts with closed structures require holes to be added for uncured resin to escape

	SLS
Materials	Powdered nylon blends
Layer Height Range	0.06 mm - 0.15 mm
Dimensional Accuracy	±300 μm
Price	Desktop starting at $9000, larger scale from $10,000-$100,000
Material Price	$100-$500/kg
Material Consumption	Varied; approx. 50% of unsintered powder per build volume (average 300 x 300 x 300 mm) is not re-usable
Additional Costs / Considerations	Specialized ventilation systems Explosion proof vacuums (some dust may be combustible, requiring only a small spark to ignite) Starting at $1000 Post-processing, parts cleaning cabinet ($3000 and up), and powder recycling stations ($2,000-$12,000) are required Operation and equipment maintenance requires skilled operator High-powered lasers can be hazardous, specialized space needed PPE (nitrile gloves, safety glasses or goggles) for handling and clean-up of powder
Pros	No need for additional support materials Can print large number of parts simultaneously without affecting print times Strong layer adhesion
Cons	The raw material is a powder that is hazardous if inhaled Only suitable for large, high-volume production; Small and medium single prints are not economical Grainy, sandy surface finish Materials are typically proprietary Producing large flat surfaces and small holes can be problematic, as they are susceptible to warping and over-sintering Prints are porous in nature (typically around 30%), requiring special post-processing for use in humid environments Prints require a cooling time of up to 12 hours Material escape holes must be added to designs to remove unsintered powder from hollow sections