What is 3D printing?
Every 3D printer builds parts based on the same main principle: a digital model is turned into a physical three-dimensional object by adding material a layer at a time. This where the alternative term Additive Manufacturing comes from.
The traditional manufacturing process is mostly a subtractive process, where the raw material gets wasted and reused over and over again. For example, in a car factory sheet metal is cut and shaped into specific body parts and leftover metal is later melted back down and formed into metal plates again before they can be reused for any further processes. Where the 3D printed object is created by an additive process. Layers for layer is added until the object is finalized. Each of these layers can be seen as a thinly sliced horizontal cross-section of the eventual object. This is an additive process, hence the name additive manufacturing.
FDM 3D printing ( or FFF )
There are a lot of ways to create 3D objects, but what all the 3D printing technologies have in common, it’s an additive technology. The additive technologies can differ in multiple ways, but differ mainly in the way layers are built to create an object.
The most commonly used technology in 3D printing is Fused Deposition Modeling (FDM). The FDM technology works using a plastic filament or metal wire which is unwound from a coil and supplying material to an extrusion nozzle which can turn the flow on and off. The nozzle is heated to melt the material and can be moved in both horizontal and vertical directions by a numerically controlled mechanism, directly controlled by a computer-aided manufacturing (CAM) software package. The object is produced by extruding melted material to form layers as the material hardens immediately after extrusion from the nozzle.
FDM 3D printing is also known as Fused Filament Fabrication (FFF). The technology is exactly the same, but as the FDM is trademarked, the FFF name is free to use.
Due to the high quality of FFF 3D printing, we also chose the FFF technology for our 3D printers.
3D printing technology – Delta versus Cartesian
The 3D printing market is quite competitive and each printer has its own 3D printing technology and unique capabilities, so it’s important to know which printer technology is most suited for the results you want to achieve. As most 3D printers, Tractus3D printers use the FFF 3D printing method (also known as FDM 3D printing), which means everything is printed layer by layer using filament.
In the FDM 3D printing technology, two types of printing systems can be distinguished: Cartesian and Delta. The biggest difference between these two systems is the method of moving. Because each system has its own way of moving, you will achieve different results.
Cartesian 3D printer
Cartesian printers owe their name to the Cartesian coordinate system they use, which was invented by Rene Descartes. They don’t just function based on an X and Y coordinate system, but also drive the print head on a mechanism that travels linearly on both the X and Y axis.
Cartesian printers move from left to right, front to back and up and down. Simply put, it gets from A to B by moving just one axis at a time. Most Cartesian printers consist of a square, moving print bed. Instead of having the nozzle move towards the print bed, the print bed moves towards the nozzle in some cases.
Cartesian 3D printers see their downside in the fact that their moving parts are quite heavy. Because of this, it is hard for a Cartesian printer to stop or change direction in an instant. The constant jerking of the platform can lead to prints coming loose and to inaccurate prints, especially when the prints get higher.
Cartesian 3D printer disadvantages
- Hard to modify due to spatial constraints
- No instant change of direction
- Not fit to print tall objects
- Small build volume
Cartesian 3D printer advantages
- Excels in width (horizontal) prints
- Easier to learn due to understandable kinematics
- Consumer friendly
- Easy to enclose most models due to cubic frame
Delta 3D printer
Delta 3D printers also use the Cartesian coordinate system, but do not use linear-motion tracked movement to deposit the filament. Instead, they use three arms, each consisting of a parallelogram. They also move from one X or Y point to another, but do so by changing the angles of these parallelograms. The arms of a Delta 3D printer hang down from a fixed platform. All of the mechanics that drive the motion of the arms are located in that platform. As a result, the print head of the Delta 3D printer is a lot lighter than if it also had to contain motors for movement. This reduced weight leads to reduced inertia. By reducing the inertia, particularly at the end of a movement, the production head is able to respond quickly, while retaining its accuracy.
A Delta 3D printer usually features a circular print bed, which is immovable. Due to its circular print bed, the natural shape of a Delta printer is a circle. Therefore, rectangular objects tend to be rather small in comparison to a Cartesian 3D printer. What a 3D Delta printer excels at, in comparison to the 3D Cartesian printer, is its capability to build tall objects. Especially the highest point of the print can be made exceptionally accurate. It is also fairly easy to make them bigger, especially in height, due to their design. With an overall less complicated construction and less parts to be used, it reduces maintenance and costs. If you do not have/need a lot of horizontal space, but instead want to build a lot of layers on top of each other (vertical), then you should definitely take a Delta 3D printer.
It’s downside comes in the fact that a Delta 3D printer must be much taller than its build volume, due to the arm construction of the machine. This is why you will generally need more space to place your printer than you would with a Cartesian 3D printer.
Delta 3D printer disadvantages
- Format, it requires more space (in height)
- More difficult to pinpoint errors
- Harder to print objects with large surfaces (horizontal)
Delta 3D printer advantages
- Excels in printing in height
- Light, thus easy to move
- Instant change of direction possible
- More accurate in the centre than on outer limits
- Easy to maintain and upgrade
- High print speed and accuracy
3D printing design and files
All you need to start 3D printing, is a model in the STL file format, which is the industry standard file format that all 3D printers use. Think of STLs files as the PDFs of 3D printing: they contain all the information needed to print a model, but they are not easy to edit
When you’ve got the time, skill and right tools you can design your own 3D items with any 3D software. Most important is that you can save it as a STL file. If you aren’t very familiar with 3D design tools like AutoCAD, Photoshop CC or TinkerCAD, you can always download 3D designs on online repositories like Thingiverse, MyMiniFactory, Cults or GrabCAD.
Slicing the STL file
When you have a 3D model, the next step in the 3D printing process is to prepare it in order to make it 3D printable. This process is called slicing which means dividing a 3D model into hundreds or thousands of horizontal layers. This is all done automatically with slicing software, we recommend Simplify3D. You upload it to your slicing software which translates 3D models into instructions your printer understands. Better instructions mean better prints, so a simple software upgrade makes all the difference in the world.
3D Printing Materials
There is a large variety of 3D printing materials to choose from so it may be tough to decide on the most appropriate filament for a particular project. All 3D printing materials have their own distinctive features, strengths and weaknesses. Moreover, there are necessary factors like texture, durability, resistance, cost, etc. that need to be considered to avoid mistakes in 3D printing.
Most common used printing materials are:
And with our PRO series, you can print materials suitable for high temperatures, like:
Benefits of 3D printing
Low costs prototyping
Prototyping is one of the most important parts of the design-cycle (design, build, test, improve and re-design). 3D printed prototypes printed on a large industrial 3D printer could be ready in 1 to 5 days and, depending on size, even overnight. With traditional manufacturing a product would require 8-10 months, with 3D printing the whole cycle could be reduced to 8-10 weeks!.
Large range of special materials
There is a whole range of materials you can use for 3D printing. The most common materials used today are plastics like PLA and ABS, but there are a lot more materials. High temperature materials for specific applications, like PEEK and ULTEM, and for example woodfill with a wood like look and feel.
We live in a fast paced world where everything is required quickly and so, this is where 3D printing can really make a difference. One of the big advantages of 3D printing is that parts and products can be manufactured a lot quicker than they can using traditional methods. Complex designs can be created as a CAD model and then transformed into a reality in just a few hours. This delivers design ideas in a way that enables them to be verified quickly and designed in a short space of time. This is so advantageous over traditional methods as they can take weeks or months to go from the design stage to prototype stage and right through to the production process.
Customization of each and every part
With traditional manufacturing it is cheap to make and sell identical products to the consumer. 3D printing however, allows for easy customization. Start-up costs are low and you only needs to change the digital 3D model to create a custom part. The result is that each and every item can be customized to meet a user's specific needs without impacting the manufacturing costs or time.
Geometric complexity at no extra cost
The additive manufacturing technology allows a quick and easy build of complex shapes and figures. Many of which cannot be produced by traditional manufacturing methods. Complex designs are just as easy to 3D print as the more simple parts.
The possibility to change and improve designs as complex as you want without extra cost or time spend, is one of the hugest advantages of 3D printing. But it also enables designers to go the extra mile and go all out when it comes to new product designs.
When developing a new product are prototype the old way, there are a lot of steps made from the initial idea until the first prototype. There are many industries that have a long and drawn out production process that includes creating a CAD model, manual building a prototype (for example by molding or carving), discuss the changes, change the model, and again manual build a new prototype. And you keep following this loop until it’s ready final production. Especially the manual prototyping is a long, labor-intense and expensive part of the process.
However, one of the strong points of 3D printing is that it creates the build in one single step with no interaction from operators during this process. It is a simple case of finalizing the design and uploading it to the printer.
This is where 3D printing can remove risks. Designs can be changed and verified through creating a production-ready prototype before going ahead with the final creation. This helps to increase confidence in the design before investments are made to take it to the next level of production.
Stay ahead of competition
Innovation is one most important things companies need to do, to keep ahead of the competition. With traditional manufacturing methods this is hard and very time consuming. Whereas 3D printing gives a lot of opportunities. Develop and create multiple prototypes you can alter on every part. Show the product to investors and the target groups to gain valuable feedback. And with the Tractus3D 3D printer you can stay even further ahead of the competition, having the ability to create a life-size prototype
Confidentiality of innovation
Another of the advantages of 3d printing is that third parties can never claim your innovations for themselves. Continuous prototyping and manufacturing in-house with a 3D printer ensures that designs never leave the company premises, safeguarding your intellectual property.
Limitations of 3D printing
Lower strength & anisotropic material properties
In general, 3D printed parts are not as strong as bulk materials, due to the fact they are build layer by layer. However, with the right infill, good design and slicing, and some good post-processing finishing, 3D printer models are really well used.
Less cost-competitive at higher volumes
When it comes to large production runs, 3D printing cannot compete with traditional manufacturing processes (yet). 3D printing is still the way to go when it comes to a small number identical parts and prototyping, and less for fast and large numbers. However, we do have cases where the ROI is better when doing production with our 3D printers.
Post-processing & support removal
Most 3D printed parts are not ready for use. For example there could be support used in the print, and you can see the layers. To make the print usable, they usually require one or more post-processing steps to achieve a high quallity surface finish. Post-rpocessing steps could be: support removal, sanding, primer, painting, dipping, spraying.