Guide to 3D Printing

Learn how 3D printers work, explore the different types of 3D printers, materials, and explore applications of 3D printing.

What is 3D Printing?

3D printing or additive manufacturing (AM) technologies create three-dimensional parts from computer-aided design (CAD) models by successively adding material layer by layer until physical part is created.

While 3D printing technologies have been around since the 1980s, recent advances in machinery, materials, and software have made 3D printing accessible to a wider range of businesses, enabling more and more companies to use tools previously limited to a few high-tech industries.

Today, professional, low-cost desktop and benchtop 3D printers accelerate innovation and support businesses in various industries including engineering, manufacturing, dentistry, healthcare, education, entertainment, jewelry, and audiology.

How Does 3D Printing Work?

All 3D printing processes start with a CAD model that is sent to software to prepare the design. Depending on the technology, the 3D printer might produce the part layer by layer by solidifying resin or sintering powder. The parts are then removed from the printer and post-processed for the specific application.

See how to go from design to 3D print with the Form 4 SLA 3D printer. This 5-minute video covers the basics of how to use the Form 4, from the software and materials to printing and post-processing.

 

1. Design

 

Preform software

3D printers create parts from three-dimensional models, the mathematical representations of any three-dimensional surface created using computer-aided design (CAD) software or developed from 3D scan data. The design is then exported as an STL or OBJ file readable by print preparation software.

3D printers include software to specify print settings and slice the digital model into layers that represent horizontal cross-sections of the part. Adjustable printing settings include orientation, support structures (if needed), layer height, and material. Once setup is complete, the software sends the instructions to the printer via a wireless or cable connection.

 

2. 3D Print

 

Build Space SLA

Some 3D printers use a laser to cure liquid resin into hardened plastic, others fuse small particles of polymer powder at high temperatures to build parts. Most 3D printers can run unattended until the print is complete, and modern systems automatically refill the material required for the parts from cartridges.

With Formlabs 3D printers, an online Dashboard allows you to remotely manage printers, materials, and teams.

 

 

3. Post-Process

 

post process - wash and cure

Depending on the technology and the material, the printed parts may require rinsing in isopropyl alcohol (IPA) to remove any uncured resin from their surface, post-curing to stabilize mechanical properties, manual work to remove support structures, or cleaning with compressed air or a media blaster to remove excess powder. Some of these processes can be automated with accessories.

3D printed parts can be used directly or post-processed for specific applications and the required finish by machining, priming, painting, fastening or joining. Often, 3D printing also serves as an intermediate step alongside conventional manufacturing methods, such as positives for investment casting jewelry and dental appliances, or molds for custom parts.

Types of 3D Printers

The three most established types of 3D printers for plastics parts are stereolithography (SLA), selective laser sintering (SLS), and fused deposition modeling (FDM). Formlabs offers two professional 3D printing technologies, SLA and SLS, bringing these powerful and accessible industrial fabrication tools into the creative hands of professionals around the world.

Stereolithography (SLA)

Stereolithography was the world’s first 3D printing technology, invented in the 1980s, and is still one of the most popular technologies for professionals. SLA 3D printers use a laser to cure liquid resin into hardened plastic in a process called photopolymerization.

SLA resin 3D printers have become vastly popular for their ability to produce high-accuracy, isotropic, and watertight prototypes and parts in a range of advanced materials with fine features and smooth surface finish. SLA resin formulations offer a wide range of optical, mechanical, and thermal properties to match those of standard, engineering, and industrial thermoplastics.

Resin 3D printing a great option for highly detailed prototypes requiring tight tolerances and smooth surfaces, such as molds, patterns, and functional parts. SLA 3D printers are widely used in a range of industries from engineering and product design to manufacturing, dentistry, jewelry, model making, and education.

Stereolithography is ideal for:

  • Rapid prototyping
  • Functional prototyping
  • Concept modeling
  • Short-run production
  • Dental applications
  • Jewelry prototyping and casting
Learn More About SLA 3D Printers
sla 3d printing process

Stereolithography (SLA) 3D printing uses a laser to cure liquid photopolymer resin into solid isotropic parts.

sla example 3d printed part

SLA parts have sharp edges, a smooth surface finish, and minimal visible layer lines.

Selective Laser Sintering (SLS)

Selective laser sintering (SLS) 3D printers use a high-power laser to sinter small particles of polymer powder into a solid structure. The unfused powder supports the part during printing and eliminates the need for dedicated support structures. This makes SLS ideal for complex geometries, including interior features, undercuts, thin walls, and negative features. Parts produced with SLS printing have excellent mechanical characteristics, with strength resembling that of injection-molded parts.

The most common material for selective laser sintering is nylon, a popular engineering thermoplastic with excellent mechanical properties. Nylon is lightweight, strong, and flexible, as well as stable against impact, chemicals, heat, UV light, water, and dirt.

The combination of low cost per part, high productivity, and established materials make SLS a popular choice among engineers for functional prototyping, and a cost-effective alternative to injection molding for limited-run or bridge manufacturing.

Selective laser sintering is ideal for:

  • Functional prototyping
  • End-use parts
  • Short-run, bridge, or custom manufacturing
Learn More About SLS 3D Printers
sls 3d printing process

SLS 3D printers use a high-powered laser to fuse small particles of polymer powder. 

sls example 3d printed part

SLS parts have a slightly rough surface finish, but almost no visible layer lines.

Fused Deposition Modeling (FDM)

Fused deposition modeling (FDM), also known as fused filament fabrication (FFF), is the most widely used type of 3D printing at the consumer level. FDM 3D printers work by extruding thermoplastic filaments, such as ABS (Acrylonitrile Butadiene Styrene), PLA (Polylactic Acid), through a heated nozzle, melting the material and applying the plastic layer by layer to a build platform. Each layer is laid down one at a time until the part is complete.

FDM 3D printers are well-suited for basic proof-of-concept models, as well as quick and low-cost prototyping of simple parts, such as parts that might typically be machined. However, FDM has the lowest resolution and accuracy when compared to SLA or SLS and is not the best option for printing complex designs or parts with intricate features. Higher-quality finishes may be obtained through chemical and mechanical polishing processes. Industrial FDM 3D printers use soluble supports to mitigate some of these issues and offer a wider range of engineering thermoplastics, but they also come at a steep price.

Fused deposition modeling is ideal for:

  • Basic proof-of-concept models
  • Simple prototyping
fdm 3d printing process

FDM 3D printers build parts by melting and extruding thermoplastic filament, which a printer nozzle deposits layer by layer in the build area.

fdm example 3d printed part

FDM parts tend to have visible layer lines and might show inaccuracies around complex features. 

How to Choose a Desktop 3D Printing Technology

Having trouble finding the best 3D printing process for your needs? In this video guide, we compare FDM, SLA, and SLS technologies, the most popular types of 3D printers, across the most important buying considerations.

Each 3D printing process has its own benefits and limitations that make them more suitable for certain applications. This video compares the functional and visual characteristics of FDM, SLA, and SLS printers 3D printers to help you identify the solution that best matches your requirements.

Do you need custom parts or prototypes fast? Compared to outsourcing to service providers or using traditional tools like machining, having a 3D printer in-house can save weeks of lead time. In this video, we compare the speed of FDM, SLA, and SLS 3D printing processes.

Comparing the cost of different 3D printers goes beyond sticker prices—these won’t tell you the full story of how much a 3D printed part will cost. Learn the three factors you need to consider for cost and how they compare across FDM, SLA, and SLS 3D printing technologies.

The Benefits of 3D Printing

As additive manufacturing processes build objects by adding material layer by layer, they offer a  unique set of advantages over traditional subtractive and formative manufacturing processes.

3d printed part - speed

Speed

With traditional manufacturing processes, it can take weeks or months to receive a part. 3D printing turns CAD models into physical parts within a few hours, producing parts and assemblies from one-off concept models to functional prototypes and even small production runs for testing. This allows designers and engineers to develop ideas faster, and helps companies to bring products more quickly to the market.

Engineers at the AMRC turned to 3D printing to rapidly produce 500 high-precision drilling caps used in drilling trials for Airbus, cutting the lead time from weeks to only three days.

Cost

With 3D printing, there’s no need for the costly tooling and setup associated with injection molding or machining; the same equipment can be used from prototyping to production to create parts with different geometries. As 3D printing becomes increasingly capable of producing functional end-use parts, it can complement or replace traditional manufacturing methods for a growing range of applications in low- to mid-volumes.

Pankl Racing Systems substituted machined jigs and fixtures with 3D printed parts, decreasing costs by 80-90 percent that resulted in $150,000 in savings.

low cost jigs and fixtures
gillette razor maker - 3d printed customization

Customization

From shoes to clothes and bicycles, we’re surrounded by products made in limited, uniform sizes as businesses strive to standardize products to make them economical to manufacture. With 3D printing, only the digital design needs to be changed to tailor each product to the customer without additional tooling costs. This transformation first started to gain a foothold in industries where custom fit is essential, such medicine and dentistry, but as 3D printing becomes more affordable, it’s increasingly being used to mass customize consumer products.

Gillette's Razor Maker™ gives consumers the power to create and order customized 3D printed razor handles, with the choice of 48 different designs (and counting), a variety of colors, and the option to add custom text.

Design Freedom

3D printing can create complex shapes and parts, such as overhangs, microchannels, and organic shapes, that would be costly or even impossible to produce with traditional manufacturing methods. This provides the opportunity to consolidate assemblies into less individual parts to reduce weight, alleviate weak joints, and cut down on assembly time, unleashing new possibilities for design and engineering.

Nervous System launched the first-ever 3D printed ceramic jewelry line, consisting of intricate designs that would be impossible to manufacture using any other ceramic technique.

3d jewlery - ceremics
3d part prototyping

Reduced Risk

Product development is an iterative process that requires multiple rounds of testing, evaluation, and refinement. Finding and fixing design flaws early can help companies avoid costly revisions and tooling changes down the road. With 3D printing, engineers can thoroughly test prototypes that look and perform like final products, reducing the risks of usability and manufacturability issues before moving into production.

The developers of Plaato, an optically clear airlock for homebrewing, 3D printed 1,000 prototypes to fine tune their design before investing in expensive tooling.

Applications and Uses of 3D Printing

3D printing accelerates innovation and supports businesses across a wide range of industries, including engineering, manufacturing, dentistry, healthcare, education, entertainment, jewelry, audiology, and more.
 

engineering and product design - rapid prototyping

Engineering and Product Design

Rapid prototyping with 3D printing empowers engineers and product designers to turn ideas into realistic proofs of concept, advance these concepts to high-fidelity prototypes that look and work like final products, and guide products through a series of validation stages toward mass production.

Applications:

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manufacturing process

Manufacturing

Manufacturers automate production processes and streamline workflows by prototyping tooling and directly 3D printing custom tools, molds, and manufacturing aids at far lower costs and lead times than with traditional manufacturing. This reduces manufacturing costs and defects, increases quality, speeds up assembly, and maximizes labor effectiveness.

Applications:

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digital dentistry

Dental

Digital dentistry reduces the risks and uncertainties introduced by human factors, providing higher consistency, accuracy, and precision at every stage of the workflow to improve patient care. 3D printers can produce a range of high-quality custom products and appliances at low unit costs with superior fit and repeatable results.

Applications:

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3d printers in education

Education

3D printers are multifunctional tools for immersive learning and advanced research. They can encourage creativity and expose students to professional-level technology while supporting STEAM curricula across science, engineering, art, and design.

Applications:

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3d technology in healthcare

Healthcare

Affordable, professional-grade desktop 3D printing helps doctors deliver treatments and devices customized to better serve each unique individual, opening the door to high-impact medical applications while saving organizations significant time and costs from the lab to the operating room.

Applications:

3d printed prop - model making

Entertainment

High definition physical models are widely used in sculpting, character modeling, and prop making. 3D printed parts have starred in stop-motion films, video games, bespoke costumes, and even special effects for blockbuster movies.

Applications:

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jewelry - rings molds - castable wax

Jewelry

Jewelry professionals use CAD and 3D printing to rapidly prototype designs, fit clients, and produce large batches of ready-to-cast pieces. Digital tools allow for the creation of consistent, sharply detailed pieces without the tediousness and variability of wax carving.

Applications:

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ear mold - audiology

Audiology

Hearing specialists and ear mold labs use digital workflows and 3D printing to manufacture higher quality custom ear products more consistently, and at higher volumes for applications like behind-the-ear hearing aids, hearing protection, and custom earplugs and earbuds.

Applications:

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Materials for 3D Printing

The market for 3D printing materials is wide and ever-growing, with printers for everything from plastics to metals, and even food and live tissue in development. Formlabs offers the following range of photopolymer materials for the desktop.

 

standard resin material

Standard

Standard 3D printing materials provide high resolution, fine features, and a smooth surface finish ideal for rapid prototyping, product development, and general modeling applications.

These materials are available in Black, White, and Grey with a matte finish and opaque appearance, Clear for any parts requiring translucency, and as a Color Kit to match almost any custom color.

Explore Standard Materials

Engineering

3D printing materials for engineering, manufacturing, and product design are formulated to provide advanced functionality, withstand extensive testing, perform under stress, and remain stable over time.

Engineering materials are ideal for 3D printing strong, precise concept models and prototypes to rapidly iterating through designs, assess form and fit, and optimize manufacturing processes.

Explore Engineering Materials
engineering resin materials
dental resin material

Dental

Dental resins empower dental labs and practices to rapidly manufacture a range of dental products cost-effectively in-house, from dental models to biocompatible surgical guidessplints , and orthodontic models for thermoforming retainers and aligners.

Explore Dental Materials

Medical

Medical resins empower hospitals to create patient-specific parts in a day at the point of care and support R&D for medical devices. These resins are formulated for 3D printing anatomical models, medical device and device components, and surgical planning and implant sizing tools.

Explore Medical Materials
medical 3d printing materials
jewelry resin materials - wax

Jewelry

Jewelry resins are formulated to capture breathtaking detail and create custom jewelry cost-effectively. These resins are ideal for jewelry prototyping and casting jewelry, as well as vulcanized rubber and RTV molding.

Explore Jewelry Materials

Specialty Resins

Specialty Resins push the limits of 3D printing, featuring advanced materials with unique mechanical properties that expand what’s possible with in-house fabrication on our stereolithography 3D printers. 

Explore Specialty Materials
ceremic resin material

How Much Does a 3D Printer Cost?

In recent years, high-resolution industrial 3D printers have become more affordable, intuitive, and reliable. As a result, the technology is now accessible to more businesses. Read our in-depth guide about 3D printer costs, or try our interactive tool to see if this technology makes economic sense your business.

Calculate Your Savings
3d printer cost

3D Printing Resources and FAQ

New to 3D printing? Explore our guides to learn about the key terms and specific characteristics of 3D printing to find the best solution for your business.

For further questions, 

understanding accuracy, precision and tolerance
Understanding Accuracy, Precision, and Tolerance in 3D Printing

Understanding the meaning of terms like accuracy, precision, and tolerance is imperative for achieving meaningful 3D print performance for any application. In this post, we parse through what these terms mean and how to think about them in the context of 3D printing.