What Is 3D Printing? How Does It Work?

How does 3D printing work? 

Every 3D printer builds parts based on the same main principle: a digital model that becomes into a physical 3D object by adding material a layer at a time. This where the alternative term Additive Manufacturing comes from.

3D printing is a fundamentally different way of producing parts compared to traditional subtractive (CNC Machining) or formative (Injection Molding) manufacturing technologies.

In 3D printing, no special tools are required (for example, a cutting tool with certain geometry or a mold). Instead the part is manufactured directly onto the built platform layer-by-layer, which leads to a unique set of benefits and limitations – more on this below.

3D printing process

The process always begins with a digital 3D model – the blueprint of the physical object. This model is sliced by the printer’s software into thin, 2-dimensional layers and then turned into a set of instructions in machine language (G-code) for the printer to execute. 

From here, the way a 3D printer works varies by process. For example, desktop FDM printers melt plastic filaments and lay it down onto the print platform through a nozzle (like a high-precision, computer-controlled glue gun). Large industrials machines use a laser to sinter really thin layers of metal or plastic powders.

Plastics are by far the most common, but metals can also be 3D printed now a days. The produced parts can also have different structures

Depending on the size of the part and the type of printer, a print usually takes about 4 to 18 hours to complete.

A brief history of 3D printing 

• The sci-fi author,Arthur C. Clarke , was the first to describe the basic functions of a 3D printer back in 1964.
• The first 3D printer was released in 1987 by Chuck Hull of 3D Systems and it was using the “stereolithography” (SLA) process.
• In the 90’s and 00’s other 3D printing technologies were released, including FDM by Stratasys and SLS by 3D Systems. These printers were expensive and mainly used for industrial prototyping.
• In 2009, the ASTM Committee F42 published a document establishing 3D printing as an industrial manufacturing technology.
• In the same year, the patents on FDM expired and the first low-cost, desktop 3D printers were born by the Reprap Project What once was very expensive to afford suddenly became affordable.
• According to Wohlers the adoption of 3D printing keeps growing: more than 1 million desktop 3D printers were sold globally between 2015 and 2017 and the sales of industrial metal printers almost doubled in 2017 compared to the previous year.

3D printing today has found very specific roles in the world of manufacturing. Of course, 3D printing is an evolving technology. Every year new 3D printers are released that can have a significant impact on the industry. For example, HP launched their first 3D printing system relatively late (in 2016), but it proved to be one of the most popular industrial 3D printers

Popularity of 3D printing  already by 2017.

Benefits & Limitations of 3D printing

It is important to understand the benefits and limitations of 3D printing, unfortunately since this is a rapid developed technology this type of manufacturing has its own flaws.

Benefits of 3D printing

• Geometric complexity at no extra cost
• Very low start-up costs
• Customization of every part
• Large range of (speciality) materials

Limitations of 3D printing

• Lower strength & anisotropic material properties
• Less cost-competitive at higher volumes
• Limited accuracy & tolerances
• Post-processing & support removal

Applications of 3D printing

• Aerospace
• Automotive
• Robotics
• Tooling
• Healthcare
• Design
• Cinema
• Education
• DIY

3D printing vs. Traditional Manufacturing

It is recommended that 3D printing should be ued when a single (or only a few) parts are required at a quick turnaround time and a low-cost or when the part geometry cannot be produced with any other manufacturing technology.

Here are some scenarios for when CNC machining should be used

• Medium volumes
• Relatively simple geometries
• High material requirements
• High dimensional accuracy

For larger production formative technologies like injection molding make the most financial sense.

Original Source: https://www.3dhubs.com/guides/3d-printing/?utm_campaign=Reactivation&utm_source=hs_automation&utm_medium=email&utm_content=67184471&_hsenc=p2ANqtz-8sTg5v7rEE00Ug37iC7Q9vbpQCBnilITrY7VvbvyPmgjX_N_eiV80I9LsnEGwdvMZl8NltHNji6zcbW5rN0wieeUbWBw&_hsmi=67184471#useful-resources