When it comes to using 3D printing technology to create an object, you will want it to be flawless, have the best surface quality, and be as resilient as possible. Why? Lots of reasons. A smooth surface quality: –
- is more durable
- is permeable, seals surfaces for easy cleaning and sterilizing
- is aesthetically pleasing
- improves painting, coating, or dye adherence
- is chemical resistant
- helps create additive pieces with injection molded-like surfaces
- eliminates surface flaws and so on.
But where to look for 3D printing services for the best 3D printing surface quality? And how to pick the best 3D printing surface finish for your needs? When choosing the correct finishing option, there are numerous factors to consider, such as material price, compatibility, durability, and so on.
This article will walk you through all the printing finishes used during the 3D printing process, as well as how each one may be utilized for specific purposes, so you can select the one that best meets your needs and produce the perfect 3D print object. However, since every 3D printing technique has its own set of obstacles to keep in mind when developing parts to attain smooth surfaces, here are some tips to go about it: –
For Powder-bed Fusion Technologies
- In the Z direction, lower angle gradients and curved surfaces will result in significant steps.
- Expect up skin (grainier surface and sharper edges) and down skin with multi-jet fusion technology (smoother).
- Due to thermal shrinking, erratic changes in part width, such as ribs behind a surface, may be seen through the surface.
- Thermal difficulties may cause surface damage during the cooling process if the walls are thicker than 15 mm.
- Powder extraction from designs with embossing, patterns, and finer details is tough.
For FFF & Photopolymer Technologies
- Low angle slopes and curved gradients are best avoided in the Z direction as they result in visible layers.
- The number of support structures should be reduced, particularly in essential areas. The more support your 3D model gets, the more probable it is that the removal will result in scratches or breakage.
Now that we know how to implement designs for different 3D processes, let’s move on to get a better understanding of the prime elements to achieve a high-quality surface finish.
Have A Simple Yet Versatile Design
The quality of a 3D printed part begins with an intelligent 3D design that adapts to the quality of the material and production technology. Any form can incorporate complex geometrical shapes and sizes, including lattices, and textures to create versatile 3D printed designs.
- Pick The Material, Technology, And Post-Processing Techniques Smartly– The design process determines the surface quality of your part. Pay attention to the technology, materials, and post-processing procedures you choose because they will all have an impact on the design process and play a key role in bringing out the best in your design. Make sure the design is adaptable to the technology’s specific needs, while also considering production limitations and the need for support.
- Design Guidelines Matter– By following the design guidelines for each material and technology, such as feature size, tolerance, and minimum wall thickness, failed parts and defects are less likely to occur during industrial 3D printing production. However, designers must respect the aesthetic guidelines and post-processing limitations because both can damage design elements.
- Pay Heed to Your 3D File– Even after having a cutting-edge 3D design that adheres to the design guidelines, material, and technical requirements, converting the software’s native format (CAD) into a simplified language for a printer is necessary. This is known as meshing, and it directly impacts the part’s surface quality.
Selecting The Right Material and Technology– The next step is to have the correct material and process for creating 3D printed parts with a high-quality surface finish. While each 3D printing for prototyping method creates a component layer by layer, the resolution and design constraints vary. Here are some factors to consider before calling the shots: –
- Material attributes– All finishes are not compatible with every material. The finishes on rubber and plastic parts won’t be as good as those on conventional Nylon PA12. In fact, the ultimate finish is determined by the texture of the raw materials.
- Component size– Determine the component size while choosing a 3D printing process. DLP, DLS, SLA and LCD printers have lower build volumes than FFF or powder bed fusion printers.
- Resolution– Your 3D printed part’s resolution directly impacts its quality, and it’s described in three dimensions, which are X, Y, and Z. XY is the horizontal resolution and the smallest movement that can be achieved in one layer by the laser. Smaller movements mean more details. Z is the vertical resolution or the thickness of a layer.
- Layer width– In 3D printing, the layer width or thickness is the measure of the depth of every successive addition of material. In SLA printing, the layer thicknesses are typically smaller. This is due to the XY-resolution, which is much higher than that of other 3D printing processes.
Post–Processing Is Everything
A variety of post-processing techniques available have uncovered 3D printing’s potential for almost any application. For instance, items like robotics, prosthetics, drones, or any other consumer end-use object can be finished to look and feel like traditional injection-molded parts. As well as improving the mechanical performance of components, postprocessing solutions can also protect them from UV rays and even make them waterproof. Below mentioned are the different post-processing solutions available in additive manufacturing that depends on three major factors, namely, visual appearance of the object, roughness, and its mechanical properties.
- Polishing (For all metals and polymers)- The two primary types of polishing processes that are employed to smooth rough surfaces are Abrasive Blasting and Tumble Polishing. The first employs an abrasive material to blast a component under high pressure, while the second uses an abrasive medium to rotate and vibrate components.
- Coating (For all TPUs and polyamides)- Colored parts should preferably be printed on white material. A coat of primer is normally applied to the model before it is colored.
- Dyeing or coloring (For polyamides, acrylic, polyester, elastomer, polyurethane, TPU, ABS, PEEK, etc.)- By dyeing an object, colors can penetrate the surface of the object. By using liquid dyes, color is evenly distributed throughout all surfaces of the component, even lattices, cavities, and hollowed out sections.
- Chemical finish (For all polymers)- A vapour solvent is utilized to smooth the model surface during chemical smoothing. The vapours collide with the object’s exterior covering. The layer lines fade away, leaving a smooth outermost layer with a glossy appearance.
- Metallization (For all polymers and photopolymers)- The metallization process involves applying a thin metal film onto an object’s surface by electroforming. Polymer parts mimic the visual characteristics of metal without all the weight. This procedure can raise the surface by several millimeters.
Take Away
3D printing is advancing rapidly in terms of both controlling the surface finish as well as automating the process. As a result, surface finishing has now become a design necessity that needs to be planned and decided beforehand. This is a job that requires professional care. If you are looking for 3D printing in India, check reviews thoroughly before finalizing. The next five years will be an interesting time to see what additional 3D printing processes are developed.