What is 3d printing and how does it work?

What Is 3D printing – 3D printing definition

3D printing (3DP) is a type of rapid prototyping technology. It is based on digital model files, using powdery metal or plastics and other adhesive materials to construct objects by layer-by-layer printing. It is widely used in rapid prototyping services and product development.

But do you really know what 3D printing can do and what types of 3D printing are suitable for your rapid prototyping work? In this article, you will know all the useful and essential information about 3D printing. Here are some points you will know:

• 3D printing history
• How does 3d printing work?
•     The 3D printing principle
•     3D printing process step
•             3D modeling
•             3D printing slicing
•             Printing
•             3d printing post-processing
• 3D printing types
•      SLS 3d printing
•      SLA 3d printing
•      DMLS 3D printing
•      FDM 3d printing
• Why is 3d printing important?
•       3D printing advantages
•       3D printing benefits
• 3D printing materials guide
•     3D printing materials list
•     3D printing materials cost
• How much does 3d printing cost
•     How to calculate 3d printing cost
•           3D printing cost per gram
•           3D printing cost per hour
• 3D printing applications

3D printing history

3D printing technology appeared in the mid-1990s and is the latest rapid prototyping device using light-curing and paper lamination. It works the same as ordinary printing. The printer contains liquid or powder “printing materials.”

After connecting to the computer, the “printing materials” are superimposed layer by layer under computer control, and finally, the blueprint on the computer is turned into a physical object.

This printing technology is called 3D quick printing. Now, custom and professional 3D printing services have been widely used in various industries around the world.

• In 1986, Charles Hull developed the first commercial 3D printing machine.
• In 1993, MIT won a patent for 3D printing technology.
• In 1995, the American company ZCorp obtained the Massachusetts Institute of Technology’s sole authorization and developed 3D printers.
• In 2005, Spectrum Z510, the first high-definition color 3D printer, was successfully developed by ZCorp.
• In November 2010, Urbee, the world’s first car printed by a 3D printer.
• On June 6, 2011, the world’s first 3D printed bikini was released.
• In July 2011, British researchers developed the world’s first 3D chocolate printer.
• In August 2011, engineers at the University of Southampton developed the world’s first 3D printed airplane.
• In November 2012, Scottish scientists used human cells to print artificial liver tissue using a 3D printer for the first time.
• In November 2013, SolidConcepts, a 3 Dimensional Printing company in Austin, Texas, designed and manufactured a 3D printed metal pistol.

How does 3d printing work?

1. The 3D printing principle

The working principle of 3D printing is the same as that of traditional printers. It’s just that 3D print does not spray ink, but printing materials such as liquid or powder.

The rapid prototyping device that uses light curing and paper stacking technology superimposes the printing materials layer by layer through computer control and finally becomes real.

3D printing principle

2. 3D printing process

What is the process of 3d printing? The 3d printing process steps generally include the following main steps: modeling, slicing, printing, and post-processing.

3d printing process steps

3D modeling

Generally speaking, 3D modeling is to construct a model with three-dimensional data from a three-dimensional virtual space through three-dimensional production software. Standard 3D modeling methods are as follows:

A. Download the 3D model directly

There are many websites with 3D models on the Internet, and they have many types and numbers of 3D models. You can download a variety of 3D models, and basically, they can be used for direct 3d quick printing.

B. Reverse engineering modeling through a 3D scanner

The reverse engineering modeling of the 3D scanner is to scan the real object through the scanner to obtain three-dimensional data and then process and repair it.

It can accurately describe a series of coordinate data of the three-dimensional structure and import the data into the 3D software to completely restore the object’s 3D model.

C. Modeling with 3D modeling software

At present, there are many 3D modeling software on the market, such as 3DMax, Maya, CAD, etc. software can be used for 3D modeling, and some 3D printer manufacturers also provide 3D modeling software.

• Mechanical design software: UG, Pro/E, CATIA, SOLIDWORKS, etc., can all be directly supported.
• Industrial design software: Rhino, Alias, etc.
• CG design software: 3DMAX, MAYA, Zbrush, etc., can not be used directly but can convert OBJ files to STL files.
• Autodesk 123D is a free 3D CAD software.
• 123D Catch converts ordinary photos into 3D models
• ZEdit Pro dramatically simplifies product design and other 3D quick printing work.
• 3-MATIC software directly modify, scan, and CAD data STL

3D printing slicing

What is 3d printing slicing? 3D slicing is cutting your 3D model into pieces, designing the printing path (filling density, angle, shell, etc.), and storing the sliced file in .gcode format.

A 3D printer can directly read and The file format used. Then, through the 3D printer control software, the .gcode file is sent to the printer, and the parameters of the 3D printer are controlled to move to complete printing. Its role is to communicate with the 3D printer.

3D Printing

Start the 3D printer, transfer the STL file to the 3D printer through the data line, SD card, etc., and move the Gcode file to the 3D printer. Simultaneously, load the 3D printing materials, debug the printing platform, set the printing parameters, and then the printer starts working.

It will be printed layer by layer, and the layers will be bonded with special glue, and the pattern will be fixed according to the cross-section, and the last layer will be superimposed. Finally, after layered printing, layer-by-layer bonding, and layer-by-layer stacking, a complete item will appear in front of our eyes.

3D printing post-processing

Components manufactured with professional 3d printed services usually require some degree of post-production treatment. This critical step of the 3D printing process is known as post-processing.

In short, post-processing in 3D printing refers to any operation or task that needs to be performed on a printed part or any technique used to enhance the object further.

Post-processing 3D printed components’ main options include removing support structure or excess material, polishing, Coloring or painting, and curing.

A. Remove the support structure or excess material. After the 3D printer completes its work, take out the objects, and do the post-processing.

For example, when printing some suspended structures, a supporting structure needs to be lifted, and then the upper part of the broken system can be published. Therefore, the extra support for this part needs to be removed for post-processing.

B. Polishing, sometimes, the 3D printed items’ surface will be rough (such as SLS 3d steel printing) and need to be polished. The polishing methods are concrete polishing and chemical polishing.

The three technologies commonly used are sanding, sanding, bead blasting, and vapor smoothing.

3D Printing Polishing

C. Coloring or painting, in addition to 3DP printing technology, can achieve color 3D printing. Others generally can only print a single color.

Sometimes it is necessary to color the printed objects, such as ABS plastic, photosensitive resin, nylon, metal, etc. Different materials need to use other pigments.

Other processing, after the 3DP printing powder material process is completed, some subsequent processing measures are needed to strengthen the mold forming strength and prolong the storage time, which mainly includes standing, forced curing, powder removal, coating, etc.

After the printing process is completed, the printed mold needs to stand for some time. The formed powder and the binder are entirely cured through the cross-linking reaction, the intermolecular force, etc., especially for the main component with gypsum or cement powder.

D. Sanding

The first condition for molding is the hardening between the powder and water and the binder part’s strengthening effect. A certain period has an important influence on the final molding effect.

When the mold has a preliminary hardness, additional measures can further enhance the force according to different categories, such as heating, vacuum drying, and ultraviolet light irradiation.

After the process is completed, the prepared mold has strong hardness, and other powder on the surface needs to be removed. Most of the powder around it is removed with a brush.

The remaining less powder can be removed by mechanical vibration, microwave vibration, and the wind blowing in different directions. It has also been reported that the mold is immersed in a particular solvent, which can dissolve the scattered powder, but it cannot dissolve the cured mold. Can achieve the purpose of removing excess powder

E. Curing or hardening

For the mold after powder removal and sanding. Especially molds made of gypsum-based, ceramic-based, and other water-absorbing materials. It is also necessary to consider its long-term preservation.

The standard method is to apply a layer of waterproof curing adhesive on the outside of the mold to increase its strength and prevent it from weakening due to water absorption.

Or immerse the mold in a protective polymer, such as epoxy resin, cyanoacrylate, molten paraffin, etc. The final mold can be waterproof, durable, beautiful, and not easy to deform.

3D Printing post-processing–Curing by UV curing lamp

3D printing types

What types of 3d printing are there? The types of 3-dimensional printing prototypes currently on the market are FDM fusion lamination molding technology, SLA stereolithography 3d printing technology, SLS selected area laser sintering 3d printing technology, and DLP laser molding technology.

SLA 3d printing and SLS 3d printing parts are the earliest and most widely used technique, accounting for about 70% of all rapid prototyping.

1. SLS 3d printing

Selective Laser Sintering (SLS) is an additive manufacturing technique that uses a laser as the power source to sinter powder, binding it together to create a solid structure.

Unlike stereolithography (SLA), SLS 3d rapid prototyping service does not require support structures because the part being constructed is surrounded by un-sintered powder at all times. This allows for the construction of complex geometries matching 3D data to be built.

Selective Laser Sintering-SLS 3d printing

An advantage of selective laser sintering 3d printing is that it can produce parts in nylon and rubber materials, and components are more challenging than SLA 3d rapid printing.

The advantages of SLS 3D printing technology:

• SLS rapid prototyping parts have excellent isotropic mechanical properties
• No support structure is required. It does not require a support structure. The suspended layer in the lamination process can be directly supported by unsintered powder, which should be one of SLS printing’s most significant advantages.
• The SLS 3d printing materials utilization rate is high. Because there is no need for support and no need to add a base, it is the most common material utilization rate among several 3D printing technologies. The price is relatively low, but it is more expensive than SLA.

Disadvantages of SLS 3D printing technology:

• At present, only industrial SLS systems can be widely used, so the delivery time is longer than other 3D printing technologies (such as FDM and SLA).
• SLS cannot accurately print large planes and small holes because they are prone to warping and over-processing
• The surface of SLS printed parts is rough.

2. SLA 3d printing

Stereolithography (SLA) 3d printing is an additive manufacturing process that employs a vat of liquid ultraviolet curable photopolymer resin and an ultraviolet laser to build parts layer by layer.

It can be used for various purposes, including 1:1 models and scale models. It can also be used as a master in downstream processes, such as vacuum casting.

Stereolithography (SLA)-SLA 3d printing

Advantages of SLA printing:

• SLA printing service can produce parts with very high dimensional accuracy and intricate details.
• The surface finish of the SLA model is high.
• SLA rapid prototyping can use unique materials, such as transparent, flexible, cast resin, etc.
• The printing completion time is short.

Disadvantages of SLA printing:

• SLA prototyping components are often fragile and not suitable for functional applications.

3. DMLS 3D Metal printing

Direct Metal Laser-Sintering (DMLS) is an additive manufacturing technique that uses a laser as the power source to sinter metal powder, binding the material together to create a solid structure.

Direct Metal Laser-Sintering (DMLS)-DMLS 3D printing

Advantages of DMLS printing service:

• DMLS prototyping can print any complex structure, including a hollow design, etc.
• The material utilization rate of DMLS 3d metal printing is high, the unsintered powder can be reused, and the material waste is less.

Disadvantages of DMLS technology:

• DMLS Metal 3D printers are expensive.
• Errors and accuracy are often lower than CNC machining.
• Unable to make large parts

4. FDM 3d printing

FDM 3D printing technology, short for Fused Deposition Modeling. A 3D printer running on FDM technology heats and extrudes filaments of thermoplastic materials to build parts layer by layer from the bottom.

Fused Deposition Modeling(FDM)-FDM 3d printing

Advantage of FDM 3d printing:

• FDM printing service is the most cost-effective way to produce customized thermoplastic parts and prototypes.
• Due to the high availability of the FDM printing technology, FDM’s delivery cycle is concise (as fast as the next day’s delivery).
• There are various thermoplastic materials to choose from, suitable for prototyping and some non-commercial functional applications.
• Fast forming speed and simple post-processing

Disadvantages of FDM 3d printing:

• The surface is relatively rough.
•  Monochrome printing can not mix multi-color printing at the same time.
• Compared with other 3D printing technologies, FDM has the lowest dimensional accuracy and resolution, so it is not suitable for parts with intricate details.

Why is 3d printing necessary?

3D printing is an emerging rapid prototyping technology that is rapidly developing in the manufacturing field. It has obvious advantages compared with traditional manufacturing.

It has become an effective method for the manufacture of modern models, molds, and parts.

A 3D printing prototype for organizational change is essential because it can become a powerful weapon in product innovation competition- the ability to obtain strategic elements at low costs, such as product development cycle and shorten the design to product delivery cycle reduce inventory and Investment in special equipment.

• From the perspective of economics, 3D printed reduces the transaction cost of development and breaks the constraints of economic scale effects;
• Based on the supply chain vision, 3D printed is particularly suitable for agile supply chains because it is not limited by output and can provide rapid response capabilities. However, the far-reaching impact of 3D plastic printing is the possibility of changing the structure of the supply chain;

1. 3D printing advantages and disadvantages

3D printing advantages:

• It can be used for manufacturing complex products without increasing costs
• Can be used to produce diversification product without increasing costs
• Unlimited design space
• Can print parts integrated without assembly, reduce production costs
• Reduce the development cycle of new products
• Realize unique design and improve products
• The flexible production model will change some business models.

3d printing disadvantages:

Although high-end industrial printing can realize plastic, particular metal, or ceramic printing, the materials that cannot be printed are relatively expensive and scarce.

The printer has not yet reached a mature level and cannot support the various materials encountered daily.

2. 3D printing benefits

3D printing benefits to business:

• Fast iteration of replacement parts;
• It can carry out small-scale mass production on-demand, reducing the need for extensive inventories and expensive warehousing.

3D printing benefits to society: 

• Breaking the traditional industrial sample production and promoting economic development
• Drive personalized customization
• Innovation education stimulates interest.

3D printing materials guide

1. What materials can you 3d print?

There are many different materials for 3d quick printing service. They differ in the way that the parts are created with the materials available and in separate layers.

The commonly used materials for 3d fast printing are nylon glass fiber, durable nylon material, gypsum material, aluminum material, titanium alloy, stainless steel, silver-plated, gold-plated, rubber materials.

2. 3D printing materials list

3d printing materials comparison

3. 3D printing materials cost

In addition to how much material you are using, your 3D printing cost will also depend on what type of 3D printing material you select. The majority of 3D printing materials can be categorized as one of four kinds: thermoplastics, photopolymers, polymers, and metals.

The cost will fluctuate based on the specific material and the manufacturer, but for the most part, the estimates below are what you can expect each type of material to cost.

How much does 3d printing cost? 

1. 3D Printing Cost

Is 3D printing expensive? This may be the issue you are considering. Generally, there are many types of 3D printing technologies. These technologies have different principles, but other 3D printing technologies use different materials, and the prices also vary greatly.

Considering the cheapest printing materials as an example, the following is the minimum cost reference for various printing technologies.

• FDM 3D printing: start with $2
• SLA 3D printing: start with $2
• SLS 3D printing: start with $5
• DMLS 3D printing: start with $30

2. How to calculate 3d printing cost

3D printing costs are significant to the 3D printing business. But how to calculate the cost of 3D printing? Since the calculation methods using various parameters are different, it is essential to choose an appropriate calculation method and calculate a competitive price.

Let’s take a look at some commonly used calculation methods:

3D printing cost per gram

Calculating 3D printing cost per gram. Different materials have different prices. The same materials will have excellent and lousy accuracy, so even if the materials are the same, the price will differ.

Open the 3D drawing through the 3D software to calculate the weight of the 3D model, and then multiply it by the material’s cost to get the final 3D printing price. Usually, the metal must be more expensive than plastic.

3D printing cost per hour

Another critical method for calculating the 3D printing cost is printing time. That is, you need to pay a certain fee per hour to use the 3Dprinter. Different 3D printing companies will set their hourly costs.

For example, if a company pays $2,000 for a 3D printer technology or a device with a life expectancy of 2,000 printing hours, their hourly cost is about $1.

3D printing applications

What is 3d printing used for?–3D printing applications cover many forms of technology and materials. Almost all industries you can think of can use 3D printing, such as rapid prototyping, medicine, architecture, surgery, manufacturing, space, healthcare, food, etc.

3d printing used in medicine

3D printing service is widely used to manufacture various medical instrumentation, external prostheses, and Implants devices. 3D printing makes it possible to manufacture high-dose, fast-dissolving pills, giving doctors the ability to customize and fully control drug delivery speed and strength.

3d printing used in architecture

3D printing service is used to create complex, accurate, and durable scale models quickly and cost-effectively for architects.

3d printing architecture

3d printing used in surgery

Using 3D technology to design the human extracorporeal skeleton in a few or tens of hours, including connecting pipes, electrical appliances, and medical accessories, similarly, medical skeletal physical devices can assist in physical therapy or rehabilitation.

3d printing used in manufacturing

3D printing service is widely used in the manufacturing of rapid prototyping, fast design, and Low-volume production for product development

3d printing in healthcare

3D printing services can also be used in healthcare to develop new specific replicas of bones, organs, and blood vessels.

In particular, customized medical equipment is an area that is very compatible with the characteristics of 3D printing. At present, it has good prospects in dental, orthopedic implants, and rehabilitation orthoses.

3d printing in food

3D quick printing service is widely used in food for manufacturing multiple molds and samples for food presentation and food appearance.