3D printing technology – Overview of this modern printing technology
In the field of 3D printing, there are many different types of printing technologies and methods. However, the general principle characteristics of the so-called 3D printing technologies are: creating products by overlapping many layers of materials, according to the available contours of 3D drawings (3D files).
Through this article, you will be getting acquainted with 3D printing technology and being able to master the application of this technology in production. At a minimum, you need to be familiar with and familiar with the following basic concepts:
Types of 3D printing technologies
Types of 3D printing materials
Below, I will help you explain each concept and term most concisely and understandably:
1. What is a 3D file?
Like you often say: image files, music files, etc., 3D files are a common, popular way to refer to file types containing data that can be opened/viewed in 3 dimensions.
There are many different types of 3D software available today, which means there are also many different types of 3D file formats.
3D file formats can be divided into three basic groups:
Proprietary format: each type of 3D file creation software generates its type of file format. This type of format can only be opened when you use the correct file creation software to open it. For example, .max is the format of 3ds Max software – you can only open this file when using 3ds Max software.
Neutral formats: are formats that can be opened by a variety of software. For example, .obj, open on most 3D software.
Each type of 3D file will have different characteristics. Depending on the technical requirements, technicians and designers will choose and give different specifications for the 3D file format they need.
In the field of 3D printing, if you make a file for 3D printing purposes, you should ask the designer to export the file to .stl format is best.
If you are making a file for both 3D printing and CNC molding purposes – you should ask the designer to export the file to .stp, .igs, or .xt format.
2. 3D software
As noted above, there are hundreds of different types of 3D software. Depending on the purpose of use, you will choose the appropriate software.
3D software can be divided into the following basic groups:
File opening/reading software: usually can only open some neutral, non-exclusive 3D files for viewing. No editing or very few editing features.
File creation software: there are many different companies in this field, each type of software will usually focus on one area and have outstanding strengths in a certain area. For example: creating 3D printed models, fine art, the most popular software is Zbrush.
Software for editing and processing 3D data: there are types of software that will be to process 3D files separately. For example, in the 3D printing industry, we are using 3D Simplify, Cura to cut the print file and measure the volume of materials, estimate the printing time to quote the customer.
If you approach 3D printing software as a foundry manager, you do not need to learn deeply about file creation software and 3D data processing and editing software (usually complex software). , difficult to use consumes a lot of computer resources). Just install basic, easy-to-use file-opening software and you can already have good control over production data.
3. Printing layer (in 3D printing technology)
Recalling a little bit about the concept, 3D printing technology is a technology to create products by overlaying many layers of materials on top of each other, according to the available contours of 3D drawings.
The term “printing layer” or ” layer height ” is used a lot in the 3D printing industry because this is a parameter that has a great influence on the surface smoothness, detail, accuracy, and durability of the product.
In terms of quality: the lower the printing layer, the higher the fineness, detail, and accuracy of the product.
In terms of printing time: the lower the print layer, the longer the printing time.
In terms of cost: the lower the printing layer, the more expensive the printing price.
So, if you are new to 3D printing, print a small sample first or request a small sample from 3D printing service companies to know how high the print layer should be. . Avoid choosing a printing layer that is too high, cheap but unusable because it does not guarantee detail. Or choose a print layer that is too low, increasing unnecessary costs and time.
4. Infill (hollow consistency of printed pattern)
An outstanding advantage of 3D printing over other traditional manufacturing methods is that this technology allows you to easily adjust the density, hollow inside of the product.
The infill rate can be adjusted from 0 – 100%. That is, from empty to 100% solid.
You can also choose from a variety of infill structures, such as grid, honeycomb, and square – depending on your printing purposes.
The infill ratio mainly affects the hardness of the sample and the mass of the sample. If you need a high-strength, high-strength sample, put a high infill. If you need a disposable, cost-effective, low-strength sample, you can print it empty, or set the infill to a low level of 3-5%.
5. Support in 3D Printing Technology
In 3D printing, support is the part of the structure that is created but does not belong to the model, and it will be removed during the finishing process of the product after printing.
You can understand, support is like a “scaffolding system” in construction. The job of the support is to support so that the structural protrusions of the model do not fall during the 3D printing process.
Usually, the positions of the printed pattern that are exposed to support will not look good in terms of appearance. At the same time, the more support, the more printing materials are needed.
Therefore, the task of 3D designers and 3D printing technicians is to optimize for as little support as possible.
There are some typical types of support, such as support in SLS printing technology (powder printing), which is a layer of buffer powder, which is filled and leveled after each printing layer. This type of support does not stick to the template, is reusable, and does not affect the quality of the 3D printed model.
A sample printed with FDM technology, support has not been removed
6. Types of 3D printing technology
The same principle of operation is to create a pattern by stacking layers of material on top of each other. However, many different options and solutions can apply this principle to prototyping. From there, create a lot of different 3D printing technologies.
Here are some of the most popular 3D printing technologies on the market today:
Selective Laser Sintering
Fused Deposition Modeling
Digital Light Process (DLP)
Multi Jet Fusion (MJF)
Direct Metal Laser Sintering (DMLS)
Electron Beam Melting (EBM)
7. Types of 3D printing materials
Each different printing technology will print different types of materials.
In the world, 3D printing materials have hundreds of different types of 3D printing materials. From plastic, metal, clay to materials, biological tissue or candy, sugar, edible food, etc.
At DIGMAN, for 3D printing and prototyping for the casting industry, we are using the following 3 basic materials:
7.1. PLA plastic
Among 3D printing plastics, PLA, filament, used for FDM printing technology is the most commonly used plastic.
PLA plastic is a biodegradable plastic, not resistant to water and denatured if the temperature is >65 degrees Celsius. If you print the sample and leave it out in the environment (rain, sun), within 30 days is the sample may be damaged, broken, rotten.
To keep the sample longer and more durable, you should spray an outer layer of paint, keep it in a dry place, low temperature (below 40 degrees Celsius), and avoid direct sunlight. If so, you can keep the sample for several years without any deformation.
PLA printed pattern can be smooth, polished surface with armor paper. If you want to smooth faster and don’t need too much precision, you can use acetone to smooth the surface.
7.2. ABS-like resin
This is a liquid material, used in SLA printing technology. Customers often choose SLA printing technology and ABS-like resin materials when they need to create high-precision prototyping, high surface smoothness, and high detail.
In terms of physical properties, the model printed with ABS-like resin does not decompose in contact with water; the denaturation temperature is ~ 65 degrees Celsius. That is if you put the sample in an environment with a temperature of 65 degrees Celsius or higher. There is a high chance that your print will start to distort and deform.
Patterns printed with ABS-like resin can also be smoothed with armor paper.
7.3. Casting wax
Is an extremely low ash prototyping 3D printing material, used directly as a casting model in melt casting technology?
In the past, in melt casting technology, foundries often faced difficulties in the mold-making stage to cast wax samples. Now, modern foundries are starting to switch to 3D printing for direct wax prototyping without the need for wax casting.
3D printing technology allows the foundry to easily produce models with difficult structures, with high accuracy. It can produce a single unit with fast lead time and reasonable cost.