3D printing has long since become more than just a tool for prototypes or one-off productions. A growing number of companies, including Samshion, are integrating additive manufacturing as a complementary process into their production. However, to produce components consistently and to a high standard, a deep understanding of the entire 3D printing process is crucial – from design to post-processing.
The individual steps in 3D printing: How quality is created layer by layer?
The individual steps in 3D printing: How quality is created layer by layer
Each individual process step has a direct impact on the printing result. Therefore, it is particularly important to know the steps and their specific characteristics precisely. Only those who understand the entire process can reliably achieve high-quality, precisely fitting, and functional 3D-printed components. We often guide our clients through every step to ensure consistent and precise results.
The 3D model – The beginning of every print
Whether it’s a decorative vase, a personal Mother’s Day gift, or a highly complex technical machine part: Every 3D print starts with a digital model. And Samshion team often creates custom CAD models for professional applications to meet exact functional and dimensional requirements.
In the hobby sector, many users rely on ready-made designs from platforms like Printables, Makerworld, or Thingiverse. In professional applications—especially in mechanical engineering or for functional components—it is common practice to create custom CAD models. Software solutions such as SolidWorks, Fusion 360, or Inventor are used for this purpose.
The most common file formats for 3D printing are STL, AMF, and 3MF. While STL, a pioneer in the field, was developed in the 1980s with the first 3D printers and is widely used today, the more modern 3MF format offers several advantages: smaller file size, more information such as color and printing parameters, and higher accuracy. Therefore, we recommend using the 3MF format whenever possible.
For successful printing, several important things should be considered during the modeling process:
“Flying” structures (i.e., parts without contact to the underlying layer) should be avoided, especially by beginners, as these absolutely require support structures. These not only increase material consumption but also make post-processing more difficult.
Pay attention to overhangs: Overhangs with an angle of up to approximately 45° are generally printable without problems. Steeper overhangs can cause the printed web to “hang in mid-air”—this reduces both dimensional accuracy and surface quality.
At Samshion, our engineers carefully check models for overhangs and support needs to prevent these common issues.
Slicing – The digital finishing touches before printing
Before a 3D model can actually be printed, it must be translated into a language the printer understands. This is precisely where slicing comes into play. The term is derived from the English word “slice” – and that describes the process quite well: The component is divided into many fine horizontal layers, which the printer then builds up layer by layer.
The software that handles this step is called a slicer. Based on the 3D model, it generates a so-called G-code file. This file contains all the necessary movement instructions and parameters that the printer needs for each individual layer – for example, positions, speeds, temperatures, and cooling intensity.
For FDM printing, programs like PrusaSlicer, BambuStudio, or Cura are widely used. They are often based on the open-source project Slic3r and offer a very similar user experience. Crucial printing parameters can be set here – from nozzle and heated bed temperature to printing speed and the configuration of infill structures and support material.
In contrast, the SLA process focuses on other parameters, such as exposure time, lift height, and lift speed. Each printing process has its own logic, software, and fine-tuning – which is precisely why it’s so important to really know your slicer. Ultimately, the right settings often determine the success or failure of a print project.
A particularly important note for anyone who wants to save their projects long-term: The original model cannot be reconstructed from a G-code file. Anyone who wants to make changes later should also save their projects in 3MF format. This ensures full flexibility.
And one more tip: For parts with a small contact area on the print bed, it can be helpful to activate a so-called “brim” function in the slicer. This increases the contact area and reduces the risk of warping and detachment from the print bed.
Print preparation – Without a clean system, there can be no clean result
An often underestimated but crucial factor for successful 3D printing is machine preparation. Even the best-sliced file won’t produce a good result if the print bed, nozzle, or build chamber haven’t been thoroughly cleaned and maintained.
For FDM printing, preparation begins with cleaning the heated bed, which should be degreased with isopropanol or soapy water, depending on the model. Any old filament residue on the nozzle must also be removed. Additionally, it’s important to ensure that the filament is dry and stored correctly – damp filament can lead to significant quality problems.
Anyone working with SLA printers should ensure that the build platform is clean and, if necessary, lightly sanded. The FEP film in the resin tank must be free of residue, as must the resin itself, which should be filtered through a fine sieve if needed. Otherwise, residue can lead to faulty prints or damage to the tank.
In industrial SLS processes, cleaning is even more comprehensive: The build chamber must be completely free of old powder, the laser’s protective glass must be inspected, and all moving parts, such as the recoater, must be free of any residue. The powder material itself often needs to be pre-dried.
Regardless of the method used, cleanliness and maintenance form the basis for consistently high-quality results. Guides, bearings, and other mechanical components should be regularly inspected and cleaned as needed. Careful work in this area prevents many common errors from occurring in the first place .At Samshion, rigorous machine preparation and maintenance are key to achieving repeatable, high-quality 3D-printed components.
Printing process – stability, temperature and environmental influences
Once printing starts, the most critical phase of the entire process begins – the actual printing process. Even now, there are several things to consider to ensure a clean, functional component is produced in the end.
For FDM printing, it is essential to operate the printer in a stable environment. Drafts, vibrations, or significant temperature fluctuations negatively affect print quality. An ideal location is sheltered, vibration-free, and away from direct sunlight. Particularly high ambient temperatures – above approximately 35°C – can also cause problems, as materials behave differently under these conditions.
Those printing with ABS or ASA should also ensure sufficient fresh air and good ventilation. These materials release fumes during processing that are not entirely harmless to health.
Ambient temperature also plays a crucial role in SLA printing. If it falls below 20°C, faulty curing or even complete printing failure can occur. Additionally, handling the liquid resin requires care: skin contact should be avoided, as the material can be irritating. Again, fresh air and suitable filters protect both health and the environment. Resin residue should always be stored away from light after printing, as UV radiation can unintentionally harden it.
And last but not least: The device should neither be moved nor touched during printing. Even slight vibrations can result in misalignments or surface defects in the printed image.
Post-processing – The finishing touch for perfect results
Once printing is complete, the final, but no less important, step follows: post-processing. The goal is to bring the component to a state that is both visually and functionally convincing.
With FDM printers, the part can usually be removed from the heated bed by simply bending the flexible spring steel plate. Support structures and any brims can then be removed. If the printing parameters were chosen correctly, post-processing at the contact points is minimal. However, it’s worth noting that supported areas usually don’t look quite as clean as free-printed areas. Those who have used colored filament should also be aware that sanded or machined areas will appear permanently lighter – only opaque paints will help in this case.
In SLA printing, removal is a bit more challenging. The finished models must be carefully loosened from the platform with a spatula and then cleaned in isopropanol to remove any remaining resin. Afterward, they are cured under UV light – ideally in a dedicated UV curing station. For technical resins, additional thermal post-treatment is necessary to achieve the full material properties.
Those who want to give their model components a visual or functional upgrade have several options: Painting is a widespread method. For this, the model is first sanded, cleaned and primed before being finished with acrylic paint – using a brush or airbrush.
Another option is so-called vapor smoothing, which is primarily used for ABS components. In this process, the object is treated in a container with acetone vapor, which softens the surface and causes the visible printed layers to fuse together – resulting in a smooth, glossy surface.
Even more complex, but particularly impressive, is the electroplating of 3D prints. For this process, the object is first sprayed with a conductive lacquer, such as copper lacquer, and then placed in an electroplating bath. This allows 3D prints to be coated with real metals like gold or silver – a technique primarily used in jewelry design or for exclusive components.
Samshion provides advanced post-processing solutions, and we have high-quality surface treatment suppliers including precision sanding, painting, steam smoothing, and electroplating to ensure that the final components meet precise specifications.
3D printing processes for plastics: Advantages and limitations at a glance
Numerous processes are available in the field of additive manufacturing. Three technologies have become particularly established for 3D printing with plastics: FDM (Fused Deposition Modeling), SLA (Stereolithography), and SLS (Selective Laser Sintering). Each of these processes has its own specific advantages and disadvantages – in terms of cost, material versatility, precision, and mechanical properties. In this section, we will introduce you to the three most important plastic 3D printing processes in detail.
FDM – The versatile filament printing technology for beginners and professionals
The FDM process is one of the most widespread methods in 3D printing with plastics. In this process, a thermoplastic filament is heated and extruded layer by layer through a nozzle onto the print bed. Due to their relatively low purchase price, FDM printers are particularly popular among hobbyists – hence the common term “spaghetti printer”.
Thanks to modern devices with “plug-and-print” functionality, getting started with FDM printing is particularly easy today. The range of materials is enormous: In addition to standard filaments like PLA or PETG, engineering plastics and specialty materials are also available, such as fiber-reinforced or temperature-resistant variants. Furthermore, large components can be produced with FDM, making the process attractive for prototypes and housings.
One disadvantage lies in the visible layer structure. Even at high resolution with layer heights between 0.05 mm and 0.2 mm, the print lines often remain visible. Furthermore, the material exhibits lower mechanical strength in the printing direction, as the individual layers do not completely fuse together.
Samshion team uses FDM selectively for large, functional prototypes, while ensuring optimal layer adhesion and material performance.
SLA – Highest precision through liquid resin
The SLA process uses liquid resin that is cured with pinpoint accuracy by UV light or laser. The level of detail is impressive: with typical layer heights of 0.01 mm to 0.05 mm, smooth, virtually seamless surfaces are created. Printed parts appear as if cast from a single piece – ideal for delicate applications such as jewelry, dentistry, or miniature models.
Affordable entry-level devices are now available on the market, but the technology is more complex to operate than FDM printers. In addition to the printer itself, a cleaning station with isopropanol and a curing unit are required. Furthermore, many resins pose health risks – they emit an unpleasant odor and require strict safety precautions when handling them.
SLA excels in precision, but is at a disadvantage with large formats (over approximately 50 cm) and fast production cycles. Printing speed is comparatively slow, material costs are high, and the selection of functional resins is limited. Technical resins require additional heat treatment after printing to achieve their full properties.
SLS – Industrial-grade components made from powder
The SLS process uses powdered plastic that is selectively fused with a laser. This produces extremely stable and functional components that are often comparable to injection-molded parts in terms of appearance and load-bearing capacity. Visible layer lines are virtually non-existent, making the process particularly attractive for series production or functional prototypes.
SLS printing systems are among the best in the industry – both in terms of print quality and investment costs. The machines themselves are very expensive and require additional equipment for powder recovery, cleaning, and post-processing. Removing excess powder and subsequently sandblasting the parts is time-consuming and labor-intensive.
However, those who place the highest demands on mechanical strength, dimensional accuracy and series production will find a powerful and professional solution in the SLS process.
Common problems with FDM 3D printing： how to successfully fix them？
Even with careful preparation and a good slicer profile, problems can still occur during 3D printing. Especially with FDM printing, typical errors such as poor adhesion of the first layer, warping, or stringing between parts can occur. The good news is that many of these errors can be easily fixed with targeted adjustments – both in the hardware and the software.
At Samshion, our engineers perform pre-print simulations and fine-tune slicer settings to minimize these issues before production.
The first layer is not adhering – causes and solutions
If the print detaches from the print bed immediately after printing, this is usually due to insufficient adhesion of the first layer. Often, the print bed is not leveled correctly, or the Z-offset – the distance between the nozzle and the bed – is too high. Modern printers allow fine-tuning of this value directly on the printer or in the slicer software.
Other causes can include a dirty heated bed or bed temperatures that are too low. In this case, cleaning the print bed with isopropanol or soap and slightly increasing the temperature in the slicer will help. A slower printing speed for the first layer also improves adhesion. If necessary, a special 3D printing adhesion spray such as 3D Lac can be used – a fine mist is sufficient and will last for several prints.
Warping – When corners of the bed come loose
Another common problem is warping: the corners of the part lift off the bed during the printing process. This is often caused by a print bed that is too cold, insufficient adhesion, or cold drafts in the room.
Remedies include an enclosed build plate, increasing the bed temperature, or using brims, rafts, or so-called “mouse ears,” which can be activated in the slicer. A clean print bed and possibly the use of 3D Lac are also helpful to ensure even adhesion.
Stringing – threads between the components
When fine plastic threads form between moving parts during printing, this is called stringing. Usually, the printing temperature is too high or the retraction settings (i.e., the retraction of the filament during movement) are not optimal.
To fix this, the temperature in the slicer can be slightly lowered and the retraction function activated or adjusted. Enabling Z-hop – that is, lifting the nozzle during movements – also reduces stringing. It is recommended to optimize retraction settings specifically with a test model or a retraction tuning tool. Samshion performs precise retraction tuning for each material to minimize stringing and improve surface finish.
Oozing and blobs – When it drips or clumps
Excessive or uncontrolled filament extrusion leads to unclean surfaces with blobs or oozing. Temperature and retraction play a crucial role here as well. Lowering the printing temperature by a few degrees and readjusting the retraction settings can usually resolve the problem.
Another reason for oozing can be damp filament. Hygroscopic materials like nylon, TPU, or PETG, in particular, absorb moisture quickly and should be dried regularly – ideally in a filament drying container or a drying oven.
Elephant’s foot – The first layer is too wide
A common problem in FDM printing is the so-called elephant’s foot: the first layer is squashed laterally due to excessive pressure or a bed temperature that is too high. This results in inaccurate dimensions at the bottom edge. In this case, the Z-offset should be slightly increased and the heated bed temperature moderately reduced. Many slicers now also offer a special “elephant’s foot compensation” feature that automatically counteracts this issue.
Small parts come loose from the bed
Especially with small components or delicate structures, individual parts can detach during the printing process. In such cases, the contact area with the print bed is often too small, or the first layer is printed too quickly. An additional brim significantly increases the contact area. At the same time, printing the first layer more slowly helps to give the material more time to adhere.
Typical problems with SLA 3D printing and how to successfully solve them
SLA printing (stereolithography) stands for the highest precision, smooth surfaces, and the finest details. However, despite all its advantages, the process is also susceptible to typical errors that can significantly affect both print quality and the process itself. From adhesion problems to the build plate and blurry details to sticky surfaces – many of these problems can be effectively resolved with the right settings and a little experience. At Samshion, SLA printing is handled in tightly controlled conditions, with pre-print orientation, support placement, and exposure settings optimized to minimize errors.Below, we’ll show you the most common SLA problems and provide you with practical solutions.
The model does not stick to the building plate.
If the model detaches from the build platform during the first few layers or doesn’t adhere at all, this is often due to an incorrectly aligned build plate or insufficient exposure time for the first layers. First, check if the build plate is properly leveled. If not, repeat the leveling process. An excessively high Z-offset can also negatively affect adhesion – you should reduce this slightly if necessary.
Additionally, slightly increasing the first layer exposure time in the slicer software can help. For better adhesion, it can also be beneficial to lightly roughen the build plate with coarse sandpaper – this creates a microstructure to which the resin can adhere more effectively.
Print adheres to the FEP film
Another common problem with SLA printing is when the model adheres to the FEP film of the resin tank instead of the build plate. This usually indicates that the initial layers were not built up strong enough or that the adhesion to the plate is insufficient.
Several measures can remedy this: Increase the number of base layers and the exposure time of the first layers. Adjusting the so-called transition layers – the intermediate layers that lead from the base to the normal layers – can also help. Additionally, it is recommended to slightly roughen the surface of the build plate to further improve adhesion.
Distortion or crooked components
If the printed object comes out of the printer crooked or warped, this is often due to excessively fast lift speed, insufficient support, or unfavorable orientation. Too high a speed when lifting the build plate can lead to deformation because the resin has not yet fully cured.
In this case, reduce the lift speed and ensure a sufficient number of support structures, especially in sensitive or hard-to-reach areas. Large, flat models should generally be positioned at a slight angle – this reduces the stress on the individual layers and improves adhesion.
Missing details or blurry surfaces
If fine details appear blurry or unclean, overexposure may be the cause. Excessive curing time causes adjacent areas to harden slightly as well, which impairs detail. In such cases, you should slightly reduce the exposure time.
The resin used can also play a role: Old or contaminated resin loses reactivity over time. Filter the resin before printing or replace it to obtain clean, clear results.
Skinning – resin layer between the supports
With very fine structures or delicate details, thin resin films (“skin”) can form between the support structures. This is usually caused by overexposure, which also hardens the resin in these spaces.
Here it helps to reduce the exposure time in small steps and at the same time slightly decrease the density of the supports, without losing stability.
Broken supports or dropped models
If support structures break during printing or the model suddenly lies still in the tank, the cause is usually a support structure that is too thin or a resin that is unsuitable for the model’s weight. In this case, you should use thicker support structures and, if necessary, choose a stronger, harder resin.
The orientation of the model also plays a role: Large surfaces or heavy components should be printed at an angle to distribute the load more evenly and minimize the risk of slippage.
Sticky surface after printing
A sticky surface usually indicates that not all resin residue has been thoroughly removed or that the post-curing time was too short. Carefully wash the model in isopropanol (IPA) or a special cleaning alcohol, ideally in a wash station. Then, post-cure with UV light, ideally in two-minute intervals, until the part is completely dry, hard, and no longer sticky.
Air bubbles in the component
Bubbles in the finished printed object are usually caused by poorly prepared resin. Air bubbles in the resin can lead to gaps or inclusions during curing. Therefore, stir the resin slowly and evenly before each print – without stirring it up too much. Ideally, let the resin rest for a few minutes afterward or degas it to eliminate microbubbles.
Do you need support with your 3D printing project?
Whether you need a functional prototype, a perfectly fitting replacement part, or a small production run – at Samshion Rapid, we make your idea a reality. With years of experience, technical expertise, and a knack for customized solutions, we guide you through the entire 3D printing process: from design and printing to perfect post-processing.
