First-layer adhesion is critical to ensuring that your 3D print will be a success. But achieving good bed adhesion can be easier said than done. Corners unstick from the 3D printer’s build surface, <a href="https://www.wevolver.com/article/3d-print-warping" target="_blank">warping occurs</a>, and ultimately parts fail. Moreover, adhesion problems can be caused by a number of factors or any combination of issues, including bed leveling, bed temperature, extruder temperature, build plate deficiencies, <a href="https://www.wevolver.com/article/ender-3-v2-max-speed" target="_blank" rel="noopener noreferrer">slicer settings</a>, and more. Fortunately, there are several steps you can take to resolve the problem of a 3D print not sticking to print bed. In this article, we’re looking at the importance of bed adhesion when 3D printing as well as several different methods you can use to improve adhesion and, ultimately, print results.<h2>The Importance of Bed Adhesion</h2>Bed adhesion plays a crucial role in the success of a 3D print. When the first layer of a print adheres well to the bed, it provides a solid foundation for the rest of the print. This foundation is essential for ensuring a print's structural integrity and dimensional accuracy as well as minimizing the risk of defects.If good bed adhesion is not achieved, it can lead to a variety of issues, such as warping, curling, or part detachment of the print from the bed. In some cases, poor adhesion can even damage the printer itself, as detached prints may collide with the nozzle or other components. By understanding what factors influence bed adhesion, you can significantly improve the success rate of your 3D prints and minimize the risk of print failures due to poor bed adhesion.<h2>Method #1: Level the Bed</h2>One of the main reasons a 3D print may not stick to the print bed is poor bed leveling. If one side of your printer bed is even marginally higher or lower than the other side, it will affect the quality of your 3D print and how well the first layers of the print adhere to the build surface. In short, this is because the nozzle will be further away from part of the print bed and filament won’t be deposited evenly. When the nozzle is too close, it can cause the filament to be squished and spread out, resulting in thin layers and poor adhesion. Conversely, when the nozzle is too far away, the filament may not make sufficient contact with the bed, leading to weak adhesion.<a href="https://www.wevolver.com/article/filament-maker-two-3devos-industrial-grade-extruder-for-rd-and-material-innovation" target="_blank" rel="noopener noreferrer"><img src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1758709027722-SEO+ARTICLE+EMBED.png" style="width:100%px" class="fr-fic fr-dib" /></a>Ensuring your 3D printed bed is level can solve adhesion problems. Depending on the 3D printer hardware you have, you might be able to level the bed automatically or you may have to do it manually. If you are adjusting the bed level manually, one of the most popular methods for leveling a print bed is to use a piece of paper.  <iframe id="687fce2deed32030e1657d55" width="250" height="440" src="https://wevolver.com/iframe/specs/filament-maker-two?iframe=true" frameborder="0" scrolling="no"></iframe>Simply bring your 3D printer nozzle very close to the print surface and place a sheet of paper in between the nozzle and the build plate. Gradually raise the corner of the print bed using your machine’s leveling knobs until there is a bit of resistance when pulling the paper out. Repeat this on all corners of the print bed. You can also print a test <a href="https://www.wevolver.com/article/brim-vs-raft" target="_blank" rel="noopener noreferrer">skirt</a> after using the paper method to check the evenness of the first print layers. This is also a good idea because it allows you to check the level of the print bed while the machine is hot.<h2>Method #2: Change the Z-Offset</h2>The distance between the 3D printer nozzle and the build platform, known as the <a href="https://www.wevolver.com/article/z-offset" target="_blank" rel="noopener noreferrer">Z-offset</a>, may also be causing adhesion problems. In other words, if the nozzle is too close to the build surface, the first layer will be squished and won’t be evenly extruded; if it’s too far away, the filament extrusion also won’t stick to the build platform properly. The good news is that you can encourage good adhesion by positioning the 3D printer nozzle at the right distance.The z-offset can be adjusted in slicing software by changing the measurement values. Once the value is set, the z-axis will align itself accordingly to the print bed. If you are having adhesion problems, changing the z-offset should be used as a last resort. Where this method is most helpful is in situations where you are working with a thick build plate or if you are printing on a substrate. When experimenting with nozzle distance, make small adjustments and observe the results on test prints. Look for signs of proper adhesion, such as a smooth and even first layer, and adjust the nozzle distance accordingly until the desired adhesion is achieved.<h2>Method #3: Clean the Print Bed</h2>It is imperative that your print surface be clean before you start 3D printing. If there are any inconsistencies, like leftover glue or filament stuck to the print surface area, it can cause first layer adhesion problems. The <a href="https://www.wevolver.com/article/how-to-clean-3d-printer-beds-glass-pei-adhesive" target="_blank">best cleaning technique for a print bed</a> depends entirely on the build plate material. If you are working with a glass print bed that has filament or adhesive residue on it, start by removing the glass bed from the 3D printer and scraping the residue off using a dry scraper. From there, you can wash the plate with soapy water or window cleaner. It is also a good idea to give your glass build plate a final wipe using Isopropyl alcohol (IPA) or acetone. These cleaning products will help to remove any remnants of grease without damaging the glass surface. You can also follow these cleaning steps with a removable borosilicate glass print bed.A PEI build plate can also be cleaned with water and soap or IPA to remove residue. To ensure the thermoplastic bed surface remains smooth in the long-term, you can also wipe it down with acetone once a month or so. It is important not to use acetone on a thermoplastic build surface too often as it can erode the material. Ultimately, a clean, smooth print surface can help the critical initial layer of a print to adhere.Recommended reading: <a href="https://www.wevolver.com/article/how-to-clean-3d-printer-beds-glass-pei-adhesive" target="_blank" rel="noopener noreferrer">How to clean 3D printer beds: Glass, PEI, Adhesive</a><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjUwMjg3NDIzNjcwLTNkX3ByaW50ZXJfbm96emxlLmpwZyIsImVkaXRzIjp7InJlc2l6ZSI6eyJ3aWR0aCI6OTUwLCJmaXQiOiJjb3ZlciJ9fX0=" width="624" height="437" class="fr-fic fr-dii" alt="3D printer nozzle and print bed" />A clean build surface will help to promote good 3D printing bed adhesion.<h2 id="isPasted">Method #4: Increase Bed &amp; Nozzle Temperature</h2>Temperature settings play a big part in the final quality of a 3D print. Thermoplastic filaments like ABS and PETG harden as they cool, but if printed layers cool too quickly, the materials can also shrink, which causes layers to pull away from the print bed and warp. Using a heated bed, especially for higher temperature materials, can therefore help to improve bed adhesion. More than that, choosing the right bed temperature and nozzle temperature for different types of filament can also improve print outcomes. For example, ABS filament prints best with a build surface heated to between 90°C and 110°C and a nozzle temperature between 230°C and 260°C.[1] PLA, for its part, prints best with a heated bed of between 60°C and 80°C and with a nozzle temperature of 190°C and 210°C.[2]Keep in mind that the optimal bed temperature may vary depending on factors such as the specific filament brand, bed surface material, and ambient room temperature. Therefore, it may be necessary to experiment with different bed temperatures within the recommended range to find the best setting for your specific setup. Another helpful tip to improve adhesion is to print the first few layers at a slightly higher temperature to ensure that they will stick. After those first layers, you can lower the bed temperature back to the recommended degree for the rest of the print. <h2>Method #5: Use a Bed Adhesive</h2>Another reliable way to improve your 3D printer bed adhesion is to apply an adhesive directly to the build platform before you start printing. There are a number of adhesive products developed specifically for 3D printing, such as Magigoo and Stick Stick. Some of these dedicated adhesives are even designed with specific materials in mind. For example, Magigoo sells adhesive sticks tailored to polycarbonate (PC) and nylon (PA).[3] However, there are also several DIY solutions for bed adhesives: many makers have found glue sticks to be a reliable option, while others use hairspray or blue painter’s tape (best for PLA filament) or Kapton tape (best for ABS filament) to create a grippier print surface. If you do decide to use an adhesive coating on your 3D printer’s build plate, it is important to apply them evenly and in moderation to avoid excessive buildup and to always clean your build surface after the print is complete, otherwise you risk glue buildup and an uneven print surface.<img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjYxNDM1NTE2NTQyLWhhaXJzcHJheS5qcGciLCJlZGl0cyI6eyJyZXNpemUiOnsid2lkdGgiOjk1MCwiZml0IjoiY292ZXIifX19" width="624" height="459" class="fr-fic fr-dii" alt="Hairspray can " />Hairspray, glue sticks, or dedicated 3D printer adhesives can improve first layer adhesion.<h2 id="isPasted">Method #6: Adjust Speed and Cooling Settings</h2>If your 3D print isn’t sticking to the print bed, tweaking your print speed or cooling settings in slicer software can often help fix the issue. For example, setting the print speed for the first layer of your print to be slower than the rest of the build can promote better adhesion. A slower deposition rate for the first thin layer of a 3D print will help the filament to bond with the build surface.Cooling settings can also influence print bed adhesion and are particularly important for materials that are sensitive to temperature changes, such as PLA. Proper cooling can help prevent the material from warping or curling as it cools, which can lead to poor adhesion. However, excessive cooling can cause the material to cool too quickly, resulting in weak bonding between layers. For PLA, it is generally recommended to use a cooling fan at 100% speed after the first few layers have been printed. For materials like ABS, which are more sensitive to shrinking, a lower fan speed or no cooling may be more appropriate.For the best results, feel free to experiment with different settings and observe the results on test prints, making incremental adjustments until the desired adhesion is achieved. Keep in mind that the optimal settings may vary depending on factors such as the specific filament brand, printer model, and ambient room temperature. <h2>Method #7: Use a Raft or Brim</h2>There are also other slicer settings that can be implemented to <a href="https://www.wevolver.com/article/3d-print-not-sticking-to-print-bed-heres-the-solution" target="_blank" rel="noopener noreferrer">improve bed adhesion</a>, such as <a href="https://www.wevolver.com/article/brim-vs-raft" target="_blank">rafts and brims</a>. Rafts and brims are features 3D printed alongside your part to improve stability and reduce the chance of warping. They increase the footprint of the printed model to encourage adhesion, which is particularly valuable when printing parts with a smaller base. A raft essentially acts as a base to your 3D printed part and ensures that your print adheres to its surface, rather than the build platform directly. A brim, for its part, consists of a 3D printed border that connects to and extends from the edges of a 3D printed component. Brims are effective at anchoring the edges of a build to the 3D printed bed and are typically easier to remove than rafts. Most slicer programs, like Cura and Simplify3D, offer automated raft and brim features.If you are using a raft or brim, it’s important to keep in mind that these 3D print features do require additional post-processing for removal. In some cases, the removal process is easy and can be done by hand, in other cases, you might need additional tools like cutters to remove the part from the structure.Recommended reading: <a href="https://www.wevolver.com/article/brim-vs-raft" target="_blank">3D Printing Rafts vs Brims vs Skirts: How to Get Started</a><h2>Method #8: Change the Build Plate</h2>Another method for improving first layer adhesion is to change your 3D printer build surface. Some desktop FDM 3D printers have a removable plate meaning that you can swap out the build plate for a new one should the original be damaged. But even if your print bed is in fine condition, it could be worthwhile to think about using different build surfaces depending on the material you are printing with.A glass bed is a popular choice for 3D printer bed surfaces due to its smooth, flat surface and excellent thermal conductivity. The smooth surface allows for easy removal of prints once cooled and can result in a glossy, mirror-like finish on the bottom layer of the print. However, glass beds can sometimes struggle with adhesion, especially with materials like ABS, which are prone to warping. For this reason, many makers also use additional build surfaces like PEI sheets or Buildtak to improve first layer bonding. These can be applied directly to the existing build plate and are particularly effective for high-temperature filaments like ABS and PETG. Both PEI and Buildtak sheets provide a textured surface that promotes strong bonding between the filament and the bed, reducing the likelihood of print failures due to poor adhesion.To maintain BuildTak and PEI sheets, clean them regularly with isopropyl alcohol or a similar cleaning solution to remove any residue or adhesive buildup. Inspect the sheets for signs of wear or damage, such as scratches, gouges, or delamination, and replace them as needed to maintain optimal print adhesion. When removing prints from the bed, use a spatula or a putty knife to gently lift the print without damaging the sheet.Recommended reading: <a href="https://www.wevolver.com/article/3d-print-stuck-to-bed" target="_blank" rel="noopener noreferrer">3D Print Stuck to Bed: What to do?</a><h2>Conclusion </h2>These eight methods can help you with troubleshooting your 3D printer adhesion problems. Sometimes a single method—like adding a layer of glue to your print surface—will do the trick. In most cases, however, making various adjustments will result in the best adhesion and high-quality prints. In sum, ensuring a level 3D printer bed and a clean build surface, as well as using adhesive aids, and having the right print settings and printing temperature will have the best print results.<h2>Frequently Asked Questions (FAQs)</h2>Q: What is the best bed surface material for 3D printing? A: There is no one-size-fits-all answer to this question: the best print bed material depends on the type of filament being used and the specific printer setup. Common bed surface materials include glass, BuildTak, and PEI sheets. Glass works well with most filaments but can benefit from additional adhesives. PEI sheets and BuildTak are also compatible with most filaments and can offer superior adhesion for common materials like ABS.Q: How often should I level my 3D printer bed? A: The frequency of bed leveling depends on your printer's usage and the stability of its components. It is recommended to check and adjust the bed level regularly, especially before starting a new print or after making any adjustments to the printer's components.Q: Can I use household items as adhesive solutions for bed adhesion? A: Yes, some household items, such as glue sticks and hairspray, can be used as adhesive solutions to improve bed adhesion. However, it is essential to apply them evenly and in moderation to avoid excessive buildup or uneven adhesion.Q: How can I prevent prints from warping or curling during printing? A: To prevent prints from warping or curling, ensure proper bed adhesion by optimizing bed leveling, bed temperature, nozzle distance, print speed, and cooling settings. Additionally, using appropriate bed surface materials and adhesive solutions can help minimize warping and curling. For materials that are more sensitive to temperature fluctuations, such as ABS, consider using a heated enclosure to maintain a consistent printing environment.<h2>References</h2>[1] Tractus 3D, 2020. “ABS Filament” [Internet] <a href="https://tractus3d.com/materials/abs/" target="_blank">https://tractus3d.com/materials/abs/</a> [Accessed April 13, 2022][2] Tractus 3D, 2020. “PLA Filament” [Internet] <a href="https://tractus3d.com/materials/pla/" target="_blank">https://tractus3d.com/materials/pla/</a> [Accessed April 13, 2022][3] Magigoo, 2022. “Magigoo Pro PA (Nylon)” [Internet] <a href="https://magigoo.com/products/magigoo-pa/" target="_blank">https://magigoo.com/products/magigoo-pa/</a> [Accessed April 14, 2022]

Good first layer adhesion is critical to ensuring a successful 3D print.

Here are eight tried and true methods for optimizing your first layer adhesion with FDM 3D printing.

3D Print Not Sticking to Bed? 8 Ways to fix 3D Printer Bed Adhesion

The difference between rigid and flexible parts is significant. Imagine if the caster wheels on your office chair were rigid and brittle, or if your wrench was made of rubber: you’d have scratched floors, and you’d never be able to loosen a nut from its bolt. The objects simply wouldn’t perform as they’re supposed to.Fortunately, FDM 3D printing accommodates the printing of both rigid and flexible parts. For rigid parts, the most common entry-level material is PLA, a low-cost and versatile thermoplastic with good strength. And there are plenty of other options too: POM and PVC are both great for rigid 3D printed parts, while ABS is solid but with a touch more flexibility than PLA.&nbsp;When printing flexible parts using an FDM 3D printer, the options are more limited, but you can still achieve excellent results. One of the best flexible filaments is TPU, a material from the TPE family with good durability, excellent abrasion resistance, and a high level of flexibility. TPU is harder to print than PLA but easier than other flexible materials.In some cases, the choice of TPU vs PLA is clear and obvious: if flexibility is what you need, TPU is the way to go. In other situations, however, it can be a more difficult decision. This article looks at TPU vs PLA in terms of the respective material characteristics of the 3D printer filaments, giving tips on which to choose in certain situations.<h2 dir="ltr" id="isPasted">What is PLA Filament?</h2>Polylactic acid, abbreviated as PLA, is the most widely used 3D printing filament for the fused deposition modeling (<a href="https://www.wevolver.com/article/fff-vs-fdm-is-there-any-difference" target="_blank" rel="noopener noreferrer" class="atomseo-link atomseo-link-internal atomseo-link-follow atomseo-link-highlighted atomseo-status-valid">FDM/FFF</a>) printing process. Cheap, widespread, and biodegradable (it can be made from natural resources like corn starch or sugar cane), PLA nonetheless offers a good level of strength that is suitable for most prototyping projects.[1]PLA’s popularity in the world of extrusion 3D printing is also helped greatly by its low printing temperature, layer adhesion, and overall printability. Compatible with extruder temperatures as low as 180 °C and not requiring a heated bed, a spool of PLA is very easy to print, even at fast printing speeds. To improve <a href="https://www.wevolver.com/article/3d-print-not-sticking-to-print-bed-heres-the-solution" target="_blank" rel="noopener noreferrer" class="atomseo-link atomseo-link-internal atomseo-link-follow atomseo-link-highlighted atomseo-status-valid">bed adhesion</a>, the print bed surface can be lined with painter’s tape, PEI, or glue stick.[2] In general, even beginner-level hardware can process PLA without issue — something that can’t be said of engineering materials, high-performance materials, or even other common 3D printing materials like TPU.The flip side of PLA’s printability is its low level of temperature resistance. A low melting point makes for easy printing, but it means that printed parts are <a href="https://www.wevolver.com/article/3d-print-warping" target="_blank" rel="noopener noreferrer" class="atomseo-link atomseo-link-internal atomseo-link-follow atomseo-link-highlighted atomseo-status-redirect">prone to deformation and warping</a> when subjected to high temperatures. Because of this, PLA is useless for end-use parts that go near heat (parts located near automotive engines, for instance). The material has other limitations too: while its rigidity can be a benefit, its brittleness makes it unsuitable for load-bearing applications.PLA filament is widely used to make 3D printed prototypes, consumer products, biodegradable medical devices, electronics housings, and plant pots.Recommended reading: <a href="https://www.wevolver.com/article/pla-recycling" target="_blank" rel="noopener noreferrer" class="atomseo-link atomseo-link-internal atomseo-link-follow atomseo-link-highlighted atomseo-status-redirect">PLA Recycling: Can PLA 3D Printer Filament be Recycled?</a><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjQ1NjAzMTMyOTM2LTNkX3ByaW50ZWQtcG90cy5qcGciLCJlZGl0cyI6eyJyZXNpemUiOnsid2lkdGgiOjk1MCwiZml0IjoiY292ZXIifX19" style="width: 300px;" class="fr-fic fr-dib" alt="Multi colored plant pots">3D printed PLA plant pots<h3 dir="ltr" id="isPasted">PLA Filament Properties</h3><ul><li dir="ltr">Printing temperature: 180–230 °C</li><li dir="ltr">Print bed temperature: Unheated or 60–80 °C</li><li dir="ltr">Tensile strength: 50 MPa</li><li dir="ltr">Low flexibility</li><li dir="ltr">Medium durability</li></ul><h2 dir="ltr">What is TPU Filament?</h2>Thermoplastic polyurethane, known as TPU, is a flexible material that is part of the thermoplastic elastomer (TPE) family. Less elastic than other TPEs, TPU is highly durable, strong, and easier to extrude than other flexible filaments.TPU behaves partly like plastic, partly like <a href="https://www.wevolver.com/article/3d-print-rubber" target="_blank" rel="noopener noreferrer" class="atomseo-link atomseo-link-internal atomseo-link-follow atomseo-link-highlighted atomseo-status-redirect">rubber</a>, and there’s a good reason for this: the material is a block copolymer with alternating sequences of isocyanates (hard) and reacted polyol (soft). The ratio between these hard and soft segments can be altered by the material manufacturer, and this ratio ultimately determines the Shore hardness of the TPU.[3] Some applications demand a softer TPU material (i.e. 60A), while others are better with a firmer one (i.e. 95A).Although TPU is not the only flexible filament for FDM 3D printing, it is part of a small group. It also has very good abrasion resistance, chemical resistance (oil and grease), and fairly high shear strength. It is quite difficult to print (<a href="https://www.wevolver.com/article/tpu-print-settings" target="_blank" rel="noopener noreferrer" class="atomseo-link atomseo-link-internal atomseo-link-follow atomseo-link-highlighted atomseo-status-redirect">low print speeds are required</a>) but still easier than other TPEs and exhibits a low level of shrinkage. It requires PEI or painter’s tape applied to the build surface.Note that in other manufacturing processes (injection molding and stereolithography, for example) flexible parts are often made using thermosets: polymers that are liquid at room temperature and cured to become solid, after which they cannot be returned to their liquid state. There are plenty of flexible thermosetting materials, but these are incompatible with extrusion 3D printers since they cannot be melted and reformed. TPU is special because, although it is a thermoplastic, it offers material properties comparable to elastic thermosets.TPU filament is often used to make parts like caster wheels, phone cases, vibration dampeners, wearables, gel shoe orthotics, and soft-grip handles. Highly elastic TPU formulations can be used for items like gaskets and tubing.[4]Recommended reading: <a href="https://www.wevolver.com/article/what-is-tpu-material-in-3d-printing-material-properties-applications-and-technologies" target="_blank" rel="noopener noreferrer" class="atomseo-link atomseo-link-internal atomseo-link-follow atomseo-link-highlighted atomseo-status-valid">What is TPU Material in 3D printing: material properties, applications, and technologies</a><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjQ1NjAzMjA1MDczLTNkLXByaW50ZWQtc2hvZS5qcGciLCJlZGl0cyI6eyJyZXNpemUiOnsid2lkdGgiOjk1MCwiZml0IjoiY292ZXIifX19" style="width: 300px;" class="fr-fic fr-dib" alt="Green shoe 3d printed">3D printed TPU shoe<h3 dir="ltr" id="isPasted">TPU Filament Properties</h3><ul><li dir="ltr">Printing temperature: 225–235 °C</li><li dir="ltr">Print bed temperature: Unheated</li><li dir="ltr">Tensile strength: 20–55 MPa</li><li dir="ltr">High flexibility</li><li dir="ltr">Medium durability</li><li dir="ltr">Shore hardness range: 60A–95A</li></ul><h2 dir="ltr">TPU vs PLA: Which One to Choose?</h2>When faced with the choice of TPU vs PLA, 3D printer users are confronted with one obvious fact: TPU is a flexible filament, while PLA is a very rigid one. But there are other factors to consider too.Flexibility and rigidity are the main differentiating factors between TPU and PLA, so we’ll start our comparison there. Having read the previous section, it should be evident that TPU is a great material for making flexible, bendy, elastic, rubbery, or squishy 3D printed parts, while PLA is not. So if you need a 3D printer filament for an item like a shock absorber, a gasket, or a protective phone case, TPU may be an excellent choice. Conversely, if you need a stiff plastic component, PLA is the better option.Of course, you might be making parts that do not require a particularly high level or flexibility or stiffness. In that case, you might consider other important factors such as heat resistance: TPU requires a higher extruder temperature, but TPU parts consequently maintain their shape and function even at high temperatures. PLA parts, meanwhile, will begin to soften at around 60 °C so are only useful at low or normal temperatures.Another difference between TPU and PLA is tensile strength, where PLA comes out on top. Although TPU offers better durability, polylactic acid is the stronger of the two 3D printing filaments. However, TPU prints have the upper hand when it comes to abrasion resistance.Finally, the choice of PLA vs TPU may ultimately come down to simple factors like cost and printability. PLA wins out in both cases: TPU can be around three times more expensive than PLA on platforms like Amazon and is also more difficult to print, especially for beginners.<h1 dir="ltr" id="isPasted">Combining TPU and PLA in Multi-Material Prints</h1>TPU vs PLA can be combined in multi-material prints. This approach takes advantage of the unique properties of each material to create objects with enhanced functionality and aesthetics.Combining the materials in this way is similar to the injection molding technique of overmolding, which typically involves making a rigid molded component, then molding a further layer of (flexible) material over the top to improve ergonomics, grip, or shock absorption.The simplest way to combine TPU and PLA is to print separate TPU and PLA components and assemble them afterwards using adhesives, fasteners, interlocking sections, or another method.<img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjk1MTMzMDE4MzA1LXRvb3RoYnJ1c2guanBnIiwiZWRpdHMiOnsicmVzaXplIjp7IndpZHRoIjo5NTAsImZpdCI6ImNvdmVyIn19fQ==" style="width: 300px;" class="fr-fic fr-dib" alt="toothbrush">PLA and TPU can be combined as with the hard and soft segments of an overmolded toothbrush<h3 dir="ltr">Dual Extrusion Technology</h3>To successfully combine TPU and PLA in a single print without further assembly, dual extrusion technology is required. Dual extrusion 3D printers have two separate print heads, each loaded with a different material. This allows the printer to switch between materials during the printing process, enabling the creation of complex multi-material objects.When designing multi-material prints that combine TPU and PLA, you will generally need to design the part as an assembly — a set of connected components — in the CAD software, rather than a single object. Different materials can then be selected for the individual components at the slicing stage.In this way, TPU can be used to create flexible joints or hinges within a predominantly PLA structure, for example. This can result in objects with moving parts or adjustable features. Conversely, PLA can be used to provide structural support and rigidity to a primarily TPU object, enhancing its strength.However, a major challenge when combining TPU and PLA in a multi-material print is a lack of chemical bonding, which means the materials do not naturally stick together well. For this reason, creating a mechanically interlocking connection between the two materials can make the part more secure and useful. Researchers have also studied the best kind of surfaces for creating a bonded interface between the two materials.[5]Fortunately, combining the two materials with a mechanical connection is easier than ever. Cura version 5.3 and beyond comes with a <a href="https://ultimaker.com/learn/unlock-true-multi-material-printing-with-ultimaker-cura-5-3/" target="_blank" rel="noopener noreferrer" class="atomseo-link atomseo-link-external atomseo-link-follow atomseo-link-highlighted atomseo-status-valid">Generate Interlocking Structure</a> feature that automatically creates a secure interlocking area. At the moment, <a href="https://www.wevolver.com/article/printing-tpu" class="atomseo-link atomseo-link-internal atomseo-link-follow atomseo-link-highlighted atomseo-status-valid">printing TPU</a> with PLA is described as "experimental."&nbsp;<h2 dir="ltr" id="isPasted">Conclusion</h2>PLA and TPU are two very different materials, so they are not usually considered direct alternatives to one another. However, many 3D printer users will keep a stock of rigid 3D printing filament like PLA and a stock of flexible filament like TPU, putting a range of material properties at their disposal. To conclude, here is a simple table showing when to choose PLA and when to choose TPU:<div align="left" dir="ltr"><table><tbody><tr><td>PLA is better for…</td><td>TPU is better for…</td></tr><tr><td>Rigid parts</td><td>Flexible parts</td></tr><tr><td>Strong parts</td><td>Durable parts</td></tr><tr><td>Affordable parts</td><td>Temperature-resistant parts</td></tr><tr><td>Easy-to-print parts</td><td>Abrasion-resistant parts</td></tr><tr><td>Food-safe parts</td><td>Oil-resistant parts</td></tr></tbody></table></div><h1 dir="ltr" id="isPasted">FAQs</h1>What is the main difference between TPU and PLA?TPU is a flexible, elastic, and durable material, while PLA is a rigid, biodegradable material that is easier to print with.Can I use both TPU and PLA in the same print?Yes, you can use both materials in the same print if your 3D printer supports multi-material printing. This allows you to take advantage of the properties of both materials in a single object.Which material is better for prototyping and functional parts?It depends on the requirements of the specific part. TPU is better for parts that require flexibility and durability, while PLA is more suitable for rigid parts with fine details.Is PLA or TPU more environmentally friendly?PLA is a biodegradable material made from renewable resources, making it more environmentally friendly than TPU. However, TPU can be more durable and long-lasting, potentially reducing waste in certain applications.What are some common applications for TPU and PLA?TPU is commonly used for wearable items, flexible parts, and objects that require impact resistance. PLA is often used for decorative prints, prototypes, and rigid parts with fine details.<h1 dir="ltr">References</h1>[1] Humphreys R. <a href="https://polymerinnovationblog.com/from-corn-to-poly-lactic-acid-pla-fermentation-in-action/" target="_blank" rel="noopener noreferrer" class="atomseo-link atomseo-link-external atomseo-link-follow atomseo-link-highlighted atomseo-status-valid">From Corn to Poly Lactic Acid (PLA): Fermentation in Action</a> [Internet]. Polymer Innovation Blog. Innocentrix, LLC; 2012 [cited 2022Jan3].[2] <a href="https://ninjatek.com/learn/3d-printing-materials/pla/" target="_blank" rel="noopener noreferrer" class="atomseo-link atomseo-link-external atomseo-link-follow atomseo-link-highlighted atomseo-status-valid">3D printing with PLA</a> [Internet]. NinjaTek. 2021 [cited 2022Jan4].[3] <a href="https://www.lubrizol.com/Engineered-Polymers/About/What-is-TPU" target="_blank" rel="noopener noreferrer" class="atomseo-link atomseo-link-external atomseo-link-follow atomseo-link-highlighted atomseo-status-valid">What is TPU?</a> [Internet]. Lubrizol. [cited 2022Jan3].[4] <a href="https://prod.americanchemistry.com/industry-groups/center-for-the-polyurethanes-industry-cpi/resources2/library/thermoplastic-polyurethanes-bridge-the-gap-between-rubber-and-plastics" target="_blank" rel="noopener noreferrer" class="atomseo-link atomseo-link-external atomseo-link-follow atomseo-link-highlighted atomseo-status-redirect">Thermoplastic polyurethanes bridge the gap between rubber and plastics</a> [Internet]. American Chemistry Council. 2002 [cited 2022Jan4].[5] Brancewicz-Steinmetz E, Sawicki J, Byczkowska P. <a href="https://www.mdpi.com/1996-1944/14/21/6464" target="_blank" rel="noopener noreferrer" class="atomseo-link atomseo-link-external atomseo-link-follow atomseo-link-highlighted atomseo-status-valid">The influence of 3D printing parameters on adhesion between polylactic acid (PLA) and thermoplastic polyurethane (TPU)</a>. Materials. 2021 Oct 28;14(21):6464.

TPU vs PLA comes down to what kind of printed parts you need

FDM 3D printer users who want more elasticity from their prints often turn to TPU filament, a flexible alternative to PLA with numerous benefits. But what else should you consider when looking at TPU vs PLA?

TPU vs PLA: Choosing Between Flexible and Rigid Filament for 3D Printing

At the beginning of the 2010s, consumers and professionals looking for an affordable 3D printer had only one option: fused deposition modeling (FDM). Initially developed by additive manufacturing giant Stratasys, FDM technology involves heating up strands of thermoplastic and depositing the molten material in successive 2D layers.In 2009, however, the Stratasys patent for FDM technology expired, which enabled a number of smaller companies to begin developing their own extrusion-style 3D printers, many of which were targeted at first-time buyers.[1] And as more and more products emerged on the market — Makerbot, Ultimaker, and others — prices rapidly decreased.But it wasn’t long before buyers had a second option for low-cost plastic 3D printing. By around 2012, companies like B9Creations and Formlabs were developing and marketing affordable 3D printers that used a completely different technology: vat photopolymerization. Instead of melting and extruding plastic, these printers used bright light to selectively cure liquid resin, producing parts with fine details and an exceptionally smooth surface finish. As with FDM, the market for SLA and DLP printers grew rapidly, and this had the effect of driving down prices.Since that time, filament and resin printing technologies have remained the two main options for consumer- and professional-level 3D printing of plastic parts. And since many consumers and professionals end up choosing directly between FDM and stereolithography 3D printers, this article aims to compare the two technologies side by side, looking at their respective pros and cons, as well as suitable uses for each.<h2 dir="ltr">What is SLA/DLP printing?</h2>Stereolithography (SLA) and <a href="https://www.wevolver.com/article/digital.light.processing.3d.printing.explained">digital light processing (DLP)</a> are two closely related 3D printing technologies that both use liquid resin as a printing material. They can both be classified as vat photopolymerization technologies: the printing process takes place within a vat filled with liquid resin, and that resin undergoes photopolymerization, a light-induced chemical reaction where it changes from liquid to solid.So how exactly does resin 3D printing work? First, we’ll look at how photopolymerization 3D printing works in general, then we’ll see how SLA printers differ from DLP printers.<h2 dir="ltr" id="isPasted">The resin 3D printing process</h2>Resin 3D printing technology relies on the process of photopolymerization. It uses liquid resin as a printing material, and this liquid can be turned into a solid when exposed to light. However, that doesn’t really explain how resin 3D printers are capable of creating highly detailed 3D objects such as prototypes, models, dental aligners, and jewelry patterns.To make 3D shapes, resin 3D printers work in ways that are broadly similar to other 3D printers. That is, they form successive layers of 2D shapes, resulting in a final 3D shape consisting of all those layers joined together. But their method of creating each 2D layer is highly unique: stereolithography and DLP 3D printers use a precise UV light source to cure a 2D pattern into the liquid resin; only the pattern area of the resin hardens, while the rest remains liquid.<img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjQ1NjAyNDAwODg3LXNsYV8zZF9wcmludGVyLmpwZyIsImVkaXRzIjp7InJlc2l6ZSI6eyJ3aWR0aCI6OTUwLCJmaXQiOiJjb3ZlciJ9fX0=" style="width: 300px;" class="fr-fic fr-dib" alt="3D Printer using SLA Technology">SLA 3D PrinterIn order to create the following layers (and build up a 3D shape), a resin printer must create movement along the Z-axis — upwards or downwards. To achieve this, the build platform is lowered (or raised) in tiny increments <a href="https://www.wevolver.com/article/knowing-how-long-to-cure-resin-prints" target="_blank" rel="noopener noreferrer" class="atomseo-link atomseo-link-internal atomseo-link-follow atomseo-link-highlighted atomseo-status-valid">after a layer has been c</a>ured.Once each layer has been cured, the hardened resin part can be removed from the 3D printer, ready for support removal and other post-processing steps. Any remaining resin can be kept and reused.The resins used for DLP and SLA printing — technically thermoset polymers — can be rigid or flexible. Some are marketed as high-strength engineering resins, while others are sold as castable resins that can be burnt out when used as patterns during investment casting.[2]&nbsp;<h2 dir="ltr" id="isPasted">SLA vs DLP</h2>Stereolithography and digital light processing 3D printers do not use the same type of light source. SLA printers, which tend to be more expensive than DLP printers, use an ultraviolet (UV) laser to selectively cure patterns into the liquid resin.[3] These lasers effectively “draw” the pattern into the resin.DLP printers work in a different way. Instead of using a focused laser beam to draw a pattern, they use a projector lens and a series of tiny mirrors. This means that the entire 2D layer can be cured at once by flashing a 2D image into the resin tank, making the process faster than SLA.[4]A related form of resin printing is LCD printing, which is closer in nature to DLP than SLA. LCD resin printers use an LCD panel as a mask that goes between the light source and the resin in order to create 2D patterns; they are typically cheaper than both SLA and DLP systems.<h1 dir="ltr">What is FDM printing?</h1>Fused deposition modeling (FDM) — sometimes known as fused filament fabrication (FFF) — is the dominant form of 3D printing today. This is partly due to its popularity with beginners and hobbyists, though there are plenty of professional and industrial users of FDM 3D printers too: high-end FDM printers and materials can be used to make industrial parts, aerospace components, and tooling.FDM is a plastic 3D printing technology that uses spools of thermoplastic filament as feedstock. During the printing process, the filament is gently unwound from the spool, heated up, then deposited in layers using an extruder. Once the molten plastic is deposited (first onto the build plate, then onto subsequent layers) it cools down and solidifies, creating a hard plastic part. In some cases, the print bed is heated to improve bed adhesion.<img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjQ1NjAyNTA5NTA3LWZpbGFtZW50XzNkX3ByaW50ZXIuanBnIiwiZWRpdHMiOnsicmVzaXplIjp7IndpZHRoIjo5NTAsImZpdCI6ImNvdmVyIn19fQ==" style="width: 300px;" class="fr-fic fr-dib" alt="Filament 3D Printer">Filament 3D PrinterTo make each layer into a precise 2D shape, the printhead moves on rails along the X and Y axes while it deposits material from a nozzle. This linear movement is achieved via motors controlled by computer instructions. When a layer is complete, the printhead moves incrementally along the Z-axis (upwards) on another rail, then begins the next layer.Although it has its limitations, FDM is a versatile and reliable 3D printing process compatible with a huge range of plastic filaments; materials include affordable thermoplastics like PLA, engineering materials like polycarbonate, and high-performance materials like PEEK, as well as various blends and composites. Filament printing processes are most frequently used for prototyping, though they can also produce end-use parts.<h2 dir="ltr">Resin vs filament 3D printing</h2>Resin and filament 3D printing are two distinct processes that use different materials and technologies. As such, resin printed parts and filament printed parts can be very different.<h2 dir="ltr">Print quality</h2>On the whole, resin 3D printing processes can achieve better resolution, better surface finish, and can generally produce more high-quality parts than extrusion processes.When it comes to very fine features, a process like SLA can produce a high level of dimensional accuracy. Many SLA 3D printers are capable of printing <a href="https://www.wevolver.com/article/3d-printer-nozzle-size" target="_blank" rel="noopener noreferrer" class="atomseo-link atomseo-link-internal atomseo-link-follow atomseo-link-highlighted atomseo-status-valid">layer heights&nbsp;</a>as low as 25 microns, while most FDM 3D printers can only achieve around 100 microns.[5] Resin printers can also meet very tight tolerances.Resin printers also have the edge when it comes to surface finish. FDM 3D printing often produces layer lines (visible ridges between layers along the Z-axis) that need to be removed through sanding or other post-processing steps (which alter the final dimensions of the printed part). But SLA and DLP processes produce exceptionally smooth parts that require minimal post-processing besides support removal.Finally, parts printed with filament may be more <a href="https://www.wevolver.com/article/3d-print-warping" target="_blank" rel="noopener noreferrer" class="atomseo-link atomseo-link-internal atomseo-link-follow atomseo-link-highlighted atomseo-status-redirect">susceptible to warping and deformation</a> than those made from resin. This is due to the inevitable temperature fluctuations that occur during FDM printing.<h2 dir="ltr">Printed part durability</h2>While resin 3D printers can produce better quality parts than filament printers, they fall short when it comes to part strength and durability. Resin parts are often weak and brittle, so they have relatively few end-use applications.Not all filament is equally durable — PLA filament, for example, produces fairly brittle parts — but the huge range of material possibilities for FDM 3D printing means that very strong parts can be made. Affordable ABS filament can lead to durable parts that are tough and resistant to high temperatures, while more expensive plastics like polycarbonate and nylon produce even better results.Another advantage of filament 3D printing over resin 3D printing is its compatibility with composite materials. Thermoplastics like PLA and ABS can be reinforced with, for example, fiberglass or carbon fiber, making the printed parts far stronger.[6] This kind of reinforcement is not possible with liquid resins.<h2 dir="ltr">Build volume</h2>As a general rule, filament 3D printers have larger build areas than resin 3D printers. So while resin printers are great for highly detailed miniature parts, FDM is better for large prints.We can look at the build volumes of some market-leading products to see the difference. The incredibly popular Formlabs Form 2 SLA printer has a volume of 145 × 145 × 175 mm, which is smaller than popular FDM printers like the Ultimaker 3 (215 × 215 × 200 mm), Makerbot Replicator 2 (285 x 153 x 155 mm), and Prusa i3 MK3S (250 x 210 x 210 mm).Industrial large-format FDM 3D printers such as the BigRep Pro (1020 × 970 × 985 mm) and Stratasys F770 (1000 × 610 × 610 mm) offer huge build volumes but at a much higher price point than consumer FDM 3D printers.But while filament printing is generally better for large prints, it is possible to achieve large-format resin 3D printing if the stereolithography apparatus uses a top-down configuration rather than a bottom-up one. Bottom-up printers (i.e. most desktop resin printers) have a light source underneath the resin tank and build the part upside down. Top-down printers, however, have a light source above the resin tank and move the build platform downwards. More often used in industrial settings, these printers require a full tank of liquid resin but can print much larger parts.Within resin printing, SLA is better for large-format printing than DLP. DLP printers use projectors with a finite resolution (measured in pixels), so while it is technically possible to print large parts, resolution must be sacrificed to achieve the larger size. The principle is similar to using a video projector at home: if you place the projector close to the wall, the image will be small but sharp; if you move it further away, the image becomes larger but you can see the individual pixels.<h2 dir="ltr">Printing speed</h2>Comparing the printing speed of filament and resin 3D printers is difficult because there are many factors to consider.Firstly, not all resin printing technologies are the same: DLP is typically much faster than SLA, since it can cure a whole layer at once. However, since build volumes tend to be very small with DLP, it is usually not possible to print batches of objects during a single print job. So while the actual printing may be slower on SLA, it can achieve faster throughput if multiple units are required.FDM 3D printing sits somewhere between DLP and SLA when it comes to pure print speed, but some filaments must be printed very slowly to avoid warping and deformation. And again, filament 3D printers can have much larger build volumes than resin printers, which enables batch printing and faster throughput of duplicate parts.Finally, 3D printers (of all technologies) tend to have adjustable speeds, allowing the users to balance print times with print quality.<h1 dir="ltr">Conclusion</h1>Resin and filament 3D printers have their own unique characteristics and advantages, so when choosing between them, it is better to ask “what will the 3D printer be used for?” rather than “which 3D printing technology is better?”On the whole, resin 3D printers are best for producing small, detailed parts with an excellent surface finish. But filament printers come out on top when it comes to large or durable parts — especially those with demanding end-use applications. Resin printers are suitable for parts like castable patterns, visual prototypes, and dental devices, while filament printers offer a broader range of applications, including functional prototypes, industrial parts, and large-scale models.<h1 dir="ltr">References</h1>[1] Schoffer F. How expiring patents are ushering in the next generation of 3D printing [Internet]. TechCrunch. TechCrunch; 2016 [cited 2022Jan14]. Available from: <a href="https://techcrunch.com/2016/05/15/how-expiring-patents-are-ushering-in-the-next-generation-of-3d-printing" rel="nofollow" target="_blank" class="atomseo-link atomseo-link-external atomseo-link-nofollow atomseo-link-highlighted atomseo-status-redirect">https://techcrunch.com/2016/05/15/how-expiring-patents-are-ushering-in-the-next-generation-of-3d-printing</a>[2] Formlabs 3D Printing Materials Library [Internet]. Formlabs. [cited 2022Jan14]. Available from: <a href="https://formlabs.com/uk/materials" rel="nofollow" target="_blank" class="atomseo-link atomseo-link-external atomseo-link-nofollow atomseo-link-highlighted atomseo-status-redirect">https://formlabs.com/uk/materials</a>[3] Stereolithography [SLA] parts on demand: Stratasys Direct [Internet]. Stratasys. [cited 2022Jan14]. Available from: <a href="https://www.stratasysdirect.com/technologies/stereolithography" rel="nofollow" target="_blank" class="atomseo-link atomseo-link-external atomseo-link-nofollow atomseo-link-highlighted atomseo-status-redirect">https://www.stratasysdirect.com/technologies/stereolithography</a>[4] SLA, DLP, and LCD resin 3D printer-what are the main difference? [Internet]. Creality. [cited 2022Jan14].&nbsp;[5] Compare formlabs SLA 3D printers tech specs [Internet]. Formlabs. [cited 2022Jan14]. Available from: <a href="https://formlabs.com/uk/3d-printers/form-3/tech-specs/" rel="nofollow" target="_blank" class="atomseo-link atomseo-link-external atomseo-link-nofollow atomseo-link-highlighted">https://formlabs.com/uk/3d-printers/form-3/tech-specs/</a>[6] Heidari-Rarani M, Rafiee-Afarani M, Zahedi AM. Mechanical characterization of FDM 3D printing of continuous carbon fiber reinforced PLA composites. Composites Part B: Engineering. 2019;175:107147.

When it comes to desktop 3D printing, buyers have two main options: resin printers that use photopolymerization technology, or filament printers that extrude molten thermoplastic. Both have their strengths and weaknesses.


Resin vs. Filament 3D Printer: Pros and Cons of Curing and Extrusion

At the beginning of the 2010s, consumers and professionals looking for an affordable 3D printer had only one option: fused deposition modeling (FDM). Initially developed by additive manufacturing giant Stratasys, FDM technology involves heating up strands of thermoplastic and depositing the molten material in successive 2D layers.In 2009, however, the Stratasys patent for FDM technology expired, which enabled a number of smaller companies to begin developing their own extrusion-style 3D printers, many of which were targeted at first-time buyers.[1] And as more and more products emerged on the market — Makerbot, Ultimaker, and others — prices rapidly decreased.But it wasn’t long before buyers had a second option for low-cost plastic 3D printing. By around 2012, companies like B9Creations and Formlabs were developing and marketing affordable 3D printers that used a completely different technology: vat photopolymerization. Instead of melting and extruding plastic, these printers used bright light to selectively cure liquid resin, producing parts with fine details and an exceptionally smooth surface finish. As with FDM, the market for SLA and DLP printers grew rapidly, and this had the effect of driving down prices.Since that time, filament and resin printing technologies have remained the two main options for consumer- and professional-level 3D printing of plastic parts. And since many consumers and professionals end up choosing directly between FDM and stereolithography 3D printers, this article aims to compare the two technologies side by side, looking at their respective pros and cons, as well as suitable uses for each.<h1 dir="ltr">What is SLA/DLP printing?</h1>Stereolithography (SLA) and digital light processing (DLP) are two closely related 3D printing technologies that both use liquid resin as a printing material. They can both be classified as vat photopolymerization technologies: the printing process takes place within a&nbsp;vat&nbsp;filled with liquid resin, and that resin undergoes&nbsp;photopolymerization, a light-induced chemical reaction where it changes from liquid to solid.So how exactly does resin 3D printing work? First, we’ll look at how photopolymerization 3D printing works in general, then we’ll see how SLA printers differ from DLP printers.<h2 dir="ltr">The resin 3D printing process</h2>Resin 3D printing technology relies on the process of photopolymerization. It uses liquid resin as a printing material, and this liquid can be turned into a solid when exposed to light. However, that doesn’t really explain how resin 3D printers are capable of creating highly detailed 3D objects such as prototypes, models, dental aligners, and jewelry patterns.To make 3D shapes, resin 3D printers work in ways that are broadly similar to other 3D printers. That is, they form successive layers of 2D shapes, resulting in a final 3D shape consisting of all those layers joined together. But their method of creating each 2D layer is highly unique: stereolithography and DLP 3D printers use a precise UV light source to cure a 2D pattern into the liquid resin; only the pattern area of the resin hardens, while the rest remains liquid.<img src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1642437062330-stereolithography_3d_printer.jpg" style="width: 300px;" class="fr-fic fr-dib" alt="SLA am printer">SLA 3D PrinterIn order to create the following layers (and build up a 3D shape), a resin printer must create movement along the Z-axis — upwards or downwards. To achieve this, the build platform is lowered (or raised) in tiny increments after a layer has been cured.Once each layer has been cured, the hardened resin part can be removed from the 3D printer, ready for support removal and other post-processing steps. Any remaining resin can be kept and reused.The resins used for DLP and SLA printing — technically thermoset polymers — can be rigid or flexible. Some are marketed as high-strength engineering resins, while others are sold as castable resins that can be burnt out when used as patterns during investment casting.[2]&nbsp;<h2 dir="ltr">SLA vs DLP</h2>Stereolithography and digital light processing 3D printers do not use the same type of light source. SLA printers, which tend to be more expensive than DLP printers, use an ultraviolet (UV) laser to selectively cure patterns into the liquid resin.[3] These lasers effectively “draw” the pattern into the resin.DLP printers work in a different way. Instead of using a focused laser beam to draw a pattern, they use a projector lens and a series of tiny mirrors. This means that the entire 2D layer can be cured at once by flashing a 2D image into the resin tank, making the process faster than SLA.[4]A related form of resin printing is LCD printing, which is closer in nature to DLP than SLA. LCD resin printers use an LCD panel as a mask that goes between the light source and the resin in order to create 2D patterns; they are typically cheaper than both SLA and DLP systems.<h1 dir="ltr">What is FDM printing?</h1>Fused deposition modeling (FDM) — sometimes known as fused filament fabrication (FFF) — is the dominant form of 3D printing today. This is partly due to its popularity with beginners and hobbyists, though there are plenty of professional and industrial users of FDM 3D printers too: high-end FDM printers and materials can be used to make industrial parts, aerospace components, and tooling.FDM is a plastic 3D printing technology that uses spools of thermoplastic filament as feedstock. During the printing process, the filament is gently unwound from the spool, heated up, then deposited in layers using an extruder. Once the molten plastic is deposited (first onto the build plate, then onto subsequent layers) it cools down and solidifies, creating a hard plastic part. In some cases, the print bed is heated to improve bed adhesion.<img src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1642437222682-filament_3d_printer.jpg" style="width: 300px;" class="fr-fic fr-dib" alt="3d printer that prints a filament">Filament 3D Printer To make each layer into a precise 2D shape, the printhead moves on rails along the X and Y axes while it deposits material from a nozzle. This linear movement is achieved via motors controlled by computer instructions. When a layer is complete, the printhead moves incrementally along the Z-axis (upwards) on another rail, then begins the next layer.Although it has its limitations, FDM is a versatile and reliable 3D printing process compatible with a huge range of plastic filaments; materials include affordable thermoplastics like PLA, engineering materials like polycarbonate, and high-performance materials like PEEK, as well as various blends and composites. Filament printing processes are most frequently used for prototyping, though they can also produce end-use parts.<h1 dir="ltr">Resin vs filament 3D printing</h1>Resin and filament 3D printing are two distinct processes that use different materials and technologies. As such, resin printed parts and filament printed parts can be very different.<h2 dir="ltr">Print quality</h2>On the whole, resin 3D printing processes can achieve better resolution, better surface finish, and can generally produce more high-quality parts than extrusion processes.When it comes to very fine features, a process like SLA can produce a high level of dimensional accuracy. Many SLA 3D printers are capable of printing layer heights as low as 25 microns, while most FDM 3D printers can only achieve around 100 microns.[5] Resin printers can also meet very tight tolerances.Resin printers also have the edge when it comes to surface finish. FDM 3D printing often produces layer lines (visible ridges between layers along the Z-axis) that need to be removed through sanding or other post-processing steps (which alter the final dimensions of the printed part). But SLA and DLP processes produce exceptionally smooth parts that require minimal post-processing besides support removal.Finally, parts printed with filament may be more susceptible to warping and deformation than those made from resin. This is due to the inevitable temperature fluctuations that occur during FDM printing.<h2 dir="ltr">Printed part durability</h2>While resin 3D printers can produce better quality parts than filament printers, they fall short when it comes to part strength and durability. Resin parts are often weak and brittle, so they have relatively few end-use applications.Not all filament is equally durable — PLA filament, for example, produces fairly brittle parts — but the huge range of material possibilities for FDM 3D printing means that very strong parts can be made. Affordable ABS filament can lead to durable parts that are tough and resistant to high temperatures, while more expensive plastics like polycarbonate and nylon produce even better results.Another advantage of filament 3D printing over resin 3D printing is its compatibility with composite materials. Thermoplastics like PLA and ABS can be reinforced with, for example, fiberglass or carbon fiber, making the printed parts far stronger.[6] This kind of reinforcement is not possible with liquid resins.<h2 dir="ltr">Build volume</h2>As a general rule, filament 3D printers have larger build areas than resin 3D printers. So while resin printers are great for highly detailed miniature parts, FDM is better for large prints.We can look at the build volumes of some market-leading products to see the difference. The incredibly popular Formlabs Form 2 SLA printer has a volume of 145 × 145 × 175 mm, which is smaller than popular FDM printers like the Ultimaker 3 (215 × 215 × 200 mm), Makerbot Replicator 2 (285 x 153 x 155 mm), and Prusa i3 MK3S (250 x 210 x 210 mm).Industrial large-format FDM 3D printers such as the BigRep Pro (1020 × 970 × 985 mm) and Stratasys F770 (1000 × 610 × 610 mm) offer huge build volumes but at a much higher price point than consumer FDM 3D printers.But while filament printing is generally better for large prints, it is possible to achieve large-format resin 3D printing if the stereolithography apparatus uses a top-down configuration rather than a bottom-up one. Bottom-up printers (i.e. most desktop resin printers) have a light source underneath the resin tank and build the part upside down. Top-down printers, however, have a light source above the resin tank and move the build platform downwards. More often used in industrial settings, these printers require a full tank of liquid resin but can print much larger parts.Within resin printing, SLA is better for large-format printing than DLP. DLP printers use projectors with a finite resolution (measured in pixels), so while it is technically possible to print large parts, resolution must be sacrificed to achieve the larger size. The principle is similar to using a video projector at home: if you place the projector close to the wall, the image will be small but sharp; if you move it further away, the image becomes larger but you can see the individual pixels.<h2 dir="ltr">Printing speed</h2>Comparing the printing speed of filament and resin 3D printers is difficult because there are many factors to consider.Firstly, not all resin printing technologies are the same: DLP is typically much faster than SLA, since it can cure a whole layer at once. However, since build volumes tend to be very small with DLP, it is usually not possible to print batches of objects during a single print job. So while the actual printing may be slower on SLA, it can achieve faster throughput if multiple units are required.FDM 3D printing sits somewhere between DLP and SLA when it comes to pure print speed, but some filaments must be printed very slowly to avoid warping and deformation. And again, filament 3D printers can have much larger build volumes than resin printers, which enables batch printing and faster throughput of duplicate parts.Finally, 3D printers (of all technologies) tend to have adjustable speeds, allowing the users to balance print times with print quality.<h1 dir="ltr">Conclusion</h1>Resin and filament 3D printers have their own unique characteristics and advantages, so when choosing between them, it is better to ask “what will the 3D printer be used for?” rather than “which 3D printing technology is better?”On the whole, resin 3D printers are best for producing small, detailed parts with an excellent surface finish. But filament printers come out on top when it comes to large or durable parts — especially those with demanding end-use applications. Resin printers are suitable for parts like castable patterns, visual prototypes, and dental devices, while filament printers offer a broader range of applications, including functional prototypes, industrial parts, and large-scale models.<h1 dir="ltr">References</h1>[1] Schoffer F. How expiring patents are ushering in the next generation of 3D printing [Internet]. TechCrunch. TechCrunch; 2016 [cited 2022Jan14]. Available from: <a href="https://techcrunch.com/2016/05/15/how-expiring-patents-are-ushering-in-the-next-generation-of-3d-printing" target="_blank">https://techcrunch.com/2016/05/15/how-expiring-patents-are-ushering-in-the-next-generation-of-3d-printing</a>[2] Formlabs 3D Printing Materials Library [Internet]. Formlabs. [cited 2022Jan14]. Available from: <a href="https://formlabs.com/uk/materials" target="_blank">https://formlabs.com/uk/materials</a>[3] Stereolithography [SLA] parts on demand: Stratasys Direct [Internet]. Stratasys. [cited 2022Jan14]. Available from: <a href="https://www.stratasysdirect.com/technologies/stereolithography" target="_blank">https://www.stratasysdirect.com/technologies/stereolithography</a>[4] SLA, DLP, and LCD resin 3D printer-what are the main difference? [Internet]. Creality. [cited 2022Jan14]. Available from: <a href="https://www.creality.com/blog-detail/sla-dlp-and-lcd-resin-3d-printer-difference" target="_blank">https://www.creality.com/blog-detail/sla-dlp-and-lcd-resin-3d-printer-difference</a>[5] Compare formlabs SLA 3D printers tech specs [Internet]. Formlabs. [cited 2022Jan14]. Available from: <a href="https://formlabs.com/uk/3d-printers/form-3/tech-specs/" target="_blank">https://formlabs.com/uk/3d-printers/form-3/tech-specs/</a>[6] Heidari-Rarani M, Rafiee-Afarani M, Zahedi AM. Mechanical characterization of FDM 3D printing of continuous carbon fiber reinforced PLA composites. Composites Part B: Engineering. 2019;175:107147.

When it comes to desktop 3D printing, buyers have two main options: resin printers that use photopolymerization technology, or filament printers that extrude molten thermoplastic. Both have their strengths and weaknesses.

Resin vs Filament 3D  Printers: Pros and Cons of Curing and Extrusion

One of the most common metallic elements on earth, aluminum has been processed as a pure metal in manufacturing since the early 19th century.[1] Today, metal is amongst the most popular in industrial manufacturing, used for objects as common as cans and kitchen utensils, to high-performance components in airplanes and rockets. It is, therefore, no wonder that from its beginnings, the metal additive manufacturing industry was interested in 3D printing aluminum and aluminum alloys.As we’ll see in more detail, the story of aluminum 3D printing has not been without its challenges, but thanks to innovations on the part of metal materials and hardware developers, aluminum alloys can now be 3D printed using various additive manufacturing processes to create high-quality, lightweight parts for numerous industries.<h2 dir="ltr">Applications of 3D Printed Aluminum</h2>There are countless applications for aluminum alloys using 3D printing technologies, but many of the most high-value end-use cases are found in the automotive and aerospace industries. For decades, traditionally manufactured aluminum and aluminum alloys have been used in these industries. In aerospace, for instance, aluminum alloys are used for aircraft wings and fuselage, as well as engine components. In the automotive industry, traditionally manufactured aluminum alloys are used for vehicle bodies, transmission, engine parts, and more. Aluminum has become such a widespread material in these industries—and others—due to its excellent strength-to-weight ratio. It goes without saying that the aerospace and automotive industries are constantly striving to reduce the weight of aircraft and vehicles to improve fuel efficiency—aluminum alloys have enabled them to achieve this while still meeting strength and durability standards.3D printing has opened up even more opportunities in aerospace and automotive for creating efficient parts with low weight. By leveraging intelligent, generative design, engineers can produce optimized components that cut back on weight while maintaining strength. Divergent Technologies, a company that developed a 3D printed supercar, created its own aluminum alloys for 3D printing and has used them to produce safety and suspension components.[2] American automotive giant Ford is working with aluminum AM on an even greater scale: in collaboration with ExOne, Ford is rolling out aluminum binder jetting with the aim of producing high-volume metal parts.[3]<img src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1645510208791-3d_printed_aluminium.jpg" style="width: 300px;" class="fr-fic fr-dib">Image:&nbsp;<a href="https://www.flickr.com/photos/theexonecompany/51026559252/in/album-72157718608148713/" rel="noopener noreferrer" target="_blank">ExOne</a>Some of the stronger aluminum alloys with excellent corrosion resistance are finding 3D printing applications in the aerospace industry. Though the material has a lower strength-to-weight ratio than titanium, aluminum is substantially cheaper as a raw material. Used in combination with metal 3D printing technologies, aluminum alloys are used for parts like heat exchangers that benefit from complex geometries and thin, strong walls. In 2021, Boeing demonstrated the successful use of a 3D printed flight critical component made from aluminum—a transmission housing—on a Chinook rotorcraft.[4] Aluminum AM is also being explored and implemented for the production of replacement parts for legacy aircraft.Of course, aluminum 3D printing is not only being used and explored in the automotive and aerospace industries: it also has applications in the spheres of industrial manufacturing, motorsport, cycling, energy, robotics, jewelry, and beyond. It is also suitable for prototyping and tooling.<h2 dir="ltr">Advantages and Disadvantages of 3D Printed Aluminum</h2><h3 dir="ltr">Advantages</h3>There are many reasons why demand and interest for aluminum 3D printing have grown in recent years. First, aluminum alloys offer beneficial material properties that meet the needs of many applications. For example, aluminum is lightweight compared to steel and nickel-based alloys, while still providing sufficient strength and hardness. Aluminum alloys also offer good thermal properties as well as corrosion resistance.3D printing, for its part, brings many advantages to the table compared to traditional manufacturing processes like CNC machining and sheet metal forming. Chief among these advantages is greater design freedom. Engineers and product designers can design aluminum parts with complex geometries, including lattices and internal channels, to optimize the performance and weight of production parts.&nbsp;Metal 3D printing technologies such as laser powder bed fusion, directed energy deposition, and binder jetting also allow for greater production agility. Specifically, users can speed up turnaround times for part development (by iterating, testing, and tweaking designs), can produce small or one-off production runs, as well as achieve mass customization. Depending on the technology, aluminum 3D printing also allows for high-precision and tight tolerances without extensive post-processing. Another important benefit offered by metal 3D printing is part consolidation. Complex assemblies, like heat exchangers, that would typically be made of several different components can be redesigned into a single, more efficient part, cutting down on production and assembly times.<h3 dir="ltr">Disadvantages</h3>Naturally, there are also disadvantages to 3D printing aluminum. Depending on the application at hand, there may be better metal alloys than aluminum-based alloys. For instance, titanium alloys offer a better strength-to-weight ratio than aluminum alloys, making them more common in aviation. Aluminum alloys for 3D printing are also not as strong as nickel-based alloys or steel. That being said, aluminum alloys are less expensive than titanium and are more lightweight than steel and nickel-based materials.Perhaps the biggest disadvantage of 3D printing aluminum is related to its printability. Fortunately, massive strides have been made in recent years: today, there are a variety of high-quality aluminum alloys specifically developed for additive manufacturing. In the earlier days of metal 3D printing, aluminum presented several challenges. Conventional aluminum alloys, such as 6061, 7075, and 2024, did not undergo powder bed fusion processes well due to their reactivity and were prone to cracking. Casting aluminum alloys, such as A357, while easier to print, were slow to process and had inconsistent mechanical properties due to poor melt pool stability and energy absorption.[5] Thankfully, these issues have been overcome or at least mitigated with the creation of specially tailored aluminum alloys as well as better powder quality.&nbsp;<h2 dir="ltr">How to 3D Print Aluminum</h2>The first step in 3D printing aluminum is metal powder production. Most aluminum alloy powders on the market today are made using gas atomization. This process is capable of producing powder particles with good sphericity, which is ideal for AM. It should be noted that the characteristics and quality of powder play a big role in how the final 3D printed component turns out. For instance, in laser powder bed fusion processes, sphericity and uniformity lead to better flow and packing, resulting in more reliable prints. Powder particle sizes also range on the micron scale.<img src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1645510374536-laser_sintering.jpg" style="width: 300px;" class="fr-fic fr-dib" alt="DMLS-machine">Laser Sintering Machine for MetalIn terms of metal 3D printing technologies available for aluminum prints, there are a few options. The most common 3D printing processes for aluminum alloys are laser powder bed fusion-based including SLM (selective laser melting) and DMLS (direct metal laser sintering). These industrial technologies both rely on a laser energy source to either selectively melt or sinter thin layers of aluminum powder. The powder particles exposed to the laser fuse together and solidify. Once a layer is complete, another coating of aluminum powder is applied and the melting or sintering is repeated. This is continued until a three-dimensional object or series of objects are complete. From there, the parts must be removed from the loose powder and cleaned.&nbsp;Electron beam melting (EBM) is another PBF process that can print aluminum parts: it uses an electron beam in the 3D printer as an energy source instead of a laser. This process can actually have advantages compared to laser-based technologies, because the electron beam is less affected by the aluminum’s reflectivity, resulting in fewer thermal stresses and less risk of cracking.[6]Up until recently, binder jetting proved to be challenging for aluminum alloys. The binder jetting process is gaining prominence due to production speed compared to PBF and its capacity to use metal injection molding (MIM) metal powders, which are usually cheaper than AM powders. The problem has been that aluminum alloys have not been widely adapted for MIM in part due to their highly reactive nature. In binder jetting, a binding agent is selectively deposited onto thin layers of a dense metal powder, a process that is repeated layer by layer. The print results in a green part, which must then undergo debinding and sintering. These processes remove the binder and fuse the metal particles together to create a dense final component.Just in the past year, there have been significant advancements for aluminum binder jetting. ExOne and Ford developed a patent-pending process for binder jetting and sintering aluminum 6061—one of the most commonly used alloys.[3] Ricoh is also developing a binder jetting technology capable of processing aluminum alloys.[7] On the material side, Equispheres is pursuing the development of AlSi10Mg powders specifically tailored to binder jetting.[9]In addition to powder bed fusion and binder jetting processes, aluminum 3D printing can also be achieved using filament extrusion technologies. Aluminum filaments are made from a combination of metal powders and a polymer matrix. Wire Arc Additive Manufacturing (WAAM) has also been used to produce large-scale structures from aluminum alloys.<h2 dir="ltr" id="isPasted">Which Aluminum Alloys can be 3D Printed?</h2>Metal powder manufacturers as well as specialized AM powder producers offer a broad range of aluminum alloys for metal 3D printing. These materials are tailored for a range of different uses and applications, offering different properties and profiles. Many of the available aluminum alloys consist of a combination of metallic and metalloid elements, including aluminum, silicon, magnesium, and even copper.<img src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1645510511598-Equispheres-Aluminum-alloy-powder-1024x747-2.jpg" style="width: 300px;" class="fr-fic fr-dib">Image: <a href="https://equispheres.com/wp-content/uploads/Equispheres-Aluminum-alloy-powder-1024x747.jpg" rel="noopener noreferrer" target="_blank">Equispheres</a>AlSi10Mg is among the most common additive manufacturing aluminum alloys. It is a casting aluminum alloy characterized by good strength, toughness, and corrosion resistance. Many metal AM material providers offer AlSi10Mg. Many other common aluminum alloys for AM, such as F357 (ALSi7Mg) and AlSi12, are casting alloys. These are easier to process than other types of the aluminum alloy due to their relatively low melting point. This class of 3D printing alloy typically contains silicon, which improves the metal’s weldability.There are also other aluminum alloys for additive manufacturing, which can offer superior properties to casting alloys. For instance, advances are being made to 3D print Al6061, a high-performance hardened aluminum alloy with excellent ductility, thermal conductivity, electrical conductivity, and corrosion resistance. Al7075 is another aluminum alloy that can be 3D printed. The alloy is characterized by its high zinc content and can be heat treated to achieve exceptionally high degrees of strength. Al6061 and Al7075 have traditionally been challenging to 3D print, but thanks to advances in powder quality and the right printing parameters, it is now a possibility.It is also worth quickly mentioning Scalmalloy, a high-strength metal 3D printing material made from a combination of scandium, aluminum, and magnesium.[8] This material is stronger than traditional aluminum alloys (thanks to the addition of scandium) and offers an excellent strength-to-weight ratio and good ductility. The material is particularly interesting to the aerospace industry.<h2 dir="ltr">Conclusion</h2>Aluminum has presented challenges and incredible opportunities for the additive manufacturing industry. Today, we are seeing in real-time how aluminum 3D printing is advancing, with previously “impossible” alloys like 6061 being printed and binder jetting for aluminum alloys finally being realized. All that to say, we are only at the beginning of aluminum AM and are bound to see more amazing applications for the material being developed, from automotive to aerospace and beyond.<h2 dir="ltr">References</h2>[1] How Products Are Made, 2022. “Aluminum”. [online] <a href="http://www.madehow.com/Volume-5/Aluminum.html" target="_blank">http://www.madehow.com/Volume-5/Aluminum.html</a> [Accessed January 12, 2022][2] RDN, 2019. “Divergent, SLM near series production of 3D-printed auto safety, suspension parts”. [online] <a href="https://www.repairerdrivennews.com/2019/11/20/divergent-slm-near-series-production-of-3d-printed-auto-safety-suspension-parts/" target="_blank">https://www.repairerdrivennews.com/2019/11/20/divergent-slm-near-series-production-of-3d-printed-auto-safety-suspension-parts/</a> [Accessed January 12, 2022][3] ExOne, 2021. “ExOne and Ford have announced the automotive industry's first binder jet 3D printing and high-density sintering of aluminum”. [online] <a href="https://www.exone.com/en-US/Ford-and-ExOne-Achieve-Scientific-Breakthrough" target="_blank">https://www.exone.com/en-US/Ford-and-ExOne-Achieve-Scientific-Breakthrough</a> [Accessed January 12, 2022]&nbsp;[4] Boeing, 2021. “Chinook Flies First Flight Critical, 3D-Printed Part on Rotorcraft”. [online] <a href="https://www.boeing.com/defense/ch-47-chinook/chinook-flies-first-flight-critical-3d-printed-part-on-rotorcraft.page" target="_blank">https://www.boeing.com/defense/ch-47-chinook/chinook-flies-first-flight-critical-3d-printed-part-on-rotorcraft.page</a> [Accessed January 12, 2022][5] Equispheres, 2021. “Aluminum can be as easy as titanium”. [online] <a href="https://equispheres.com/aluminum-can-be-as-easy-as-titanium/" target="_blank">https://equispheres.com/aluminum-can-be-as-easy-as-titanium/</a> [Accessed January 12, 2022][6] Mohammad Saleh Kenevisi, Feng Lin. “Selective electron beam melting of high strength Al2024 alloy; microstructural characterization and mechanical properties”, Journal of Alloys and Compounds, Volume 843, 2020. [online] <a href="https://doi.org/10.1016/j.jallcom.2020.155866" target="_blank">https://doi.org/10.1016/j.jallcom.2020.155866</a> [Accessed January 13, 2022][7] Ricoh, 2021. “Ricoh introduces aluminium metal binder jetting technology”. [online] <a href="https://rapidfab.ricoh-europe.com/ricoh-introduces-aluminium-metal-binder-jetting-technology/" target="_blank">https://rapidfab.ricoh-europe.com/ricoh-introduces-aluminium-metal-binder-jetting-technology/</a> [Accessed January 13, 2022][8] Equispheres, 2019. “Sintering Aluminum Alloys With Binder Jet Printer Technology Unfeasible Until Now”. [online] <a href="https://equispheres.com/press-release-sintering-aluminum-alloys-with-binder-jet-printer-technology-unfeasible-until-now/" target="_blank">https://equispheres.com/press-release-sintering-aluminum-alloys-with-binder-jet-printer-technology-unfeasible-until-now/</a>&nbsp; [Accessed January 13, 2022][9] APWorks, 2021. “Scalmalloy”. [online] <a href="https://www.apworks.de/scalmalloy" target="_blank">https://www.apworks.de/scalmalloy</a> [Accessed January 13, 2022]

Though aluminum 3D printing has traditionally been a challenge, big advances have been made in recent years. Here's everything you need to know about aluminum additive manufacturing, from applications and technologies, to what alloys are available.

3D Printed Aluminum: Everything You Need to Know

Most 3D printing technologies work in a broadly similar way. They form a precise 2D shape — by extruding, <a href="https://www.wevolver.com/article/knowing-how-long-to-cure-resin-prints" target="_blank" rel="noopener noreferrer">curing</a>, or sintering material, for example — then add successive 2D shapes on top of the original one. The end result is a 3D object, with each layer tightly fused together.The process of laminated object manufacturing (LOM) is different to most 3D printing processes, though most engineers consider it a form of 3D printing. Uniquely, laminated object manufacturing uses a laser cutter to cut away sections of material in order to give the part its final shape, making it both additive (like 3D printing) and subtractive (like machining). It also resembles traditional printing, because it can use reams of ordinary office paper as feedstock.LOM is a low-cost rapid prototyping process unlike any other. And although its uses are somewhat limited, it remains an intriguing manufacturing technology for prototyping and modeling.<h2 id="isPasted">What is LOM?</h2>Laminated object manufacturing is a rapid prototyping process that bonds and cuts sheet material with a computer-controlled laser.First developed and marketed by California-based Helisys in 1991, LOM emerged as a commercial manufacturing solution the same year Stratasys introduced fused deposition modeling (FDM). [1] Helisys became Cubic Technologies in the year 2000, but is no longer in business. Mcor Technologies, founded in 2005, was another major LOM hardware company that improved the process by adding full-color capabilities. Its assets were acquired in 2019 by Irish company CleanGreen3D, which continues to develop LOM systems. [2]LOM is conceptually very different to a process like FDM. It involves bonding layers of material with an adhesive substance — creating a laminate that is much stronger than its individual layers — and laser cutting precise shapes into each layer.Though more rudimentary than today’s cutting-edge additive manufacturing processes, LOM offers important benefits like cheap feedstock, colorization, and use in normal working environments such as offices.<h2 id="isPasted">How does Laminated Object Manufacturing work?</h2>Laminated object manufacturing comprises two main steps. The first step is the lamination of sheet material; the second step is the cutting of that material with a computer-controlled laser (or cutting tool).The lamination process involves layering sheets of material one on top of the next, applying pressure and heat while using an adhesive to bind each layer together. Material is typically fed onto the build platform using rollers, with adhesive applied through a nozzle. After a layer has been rolled onto the build platform, a computer-controlled laser or cutting tool slices a 2D pattern (a cross-section of the 3D part) into it. This process is repeated layer by layer. Once the final layer has been sliced, excess material can be pulled or chiseled away, leaving behind only the precisely shaped 3D part(s).<iframe width="640" height="360" src="https://www.youtube.com/embed/GUvnz0borAI?&amp;wmode=opaque&amp;rel=0&amp;enablejsapi=1&amp;origin=https://www.wevolver.com" frameborder="0" allowfullscreen="" class="fr-draggable" data-lf-form-tracking-inspected-kn9eq4roawkarlvp="true" data-lf-yt-playback-inspected-kn9eq4roawkarlvp="true" data-lf-vimeo-playback-inspected-kn9eq4roawkarlvp="true" data-gtm-yt-inspected-10="true" id="360474519" title="Laminated Object Manufacturing"></iframe> LOM can create 3D shapes because each 2D pattern sliced onto the material represents a single cross-section of the 3D shape being built. For example, a cone shape can be created by slicing a large circle into the first layer, then slicing circles of ever-decreasing size into each subsequent layer, culminating in a single point on the final layer.Removal of the excess material can be simplified by “cross-hatching” areas outside of the model. By doing so, small cubes of the excess material can be pulled away, which is easier than removing large sections.<h2 id="isPasted">Suitable lamination materials</h2>Though principally known as a paper 3D printing technology, laminated object manufacturing can process a few types of material — depending on the particular machine.<h3>Paper</h3>Ordinary copy paper is the most popular feedstock for LOM, and the ability to use such a low-cost material is also one of the main advantages of the technology. [3]Although paper is not suitable for demanding mechanical applications, it becomes surprisingly rigid when laminated, exhibiting wood-like material properties. Incorporating hard-setting resin or other materials into the adhesive binder can further increase the solidity of the paper parts.Another advantage of paper is that some LOM machines (such as the CG-1 from CleanGreen3D) can use inkjet technology to color paper at the edges where it will be cut. This enables the low-cost <a href="https://www.wevolver.com/article/how-to-make-a-3d-model-for-printing" target="_blank" rel="noopener noreferrer">production of full-color 3D models</a>.<h3>Metal</h3>Some LOM hardware can process sheet metal in thin gauges. This results in a stronger laminated part, though stronger adhesive and a higher degree of heat may be required, and costs are higher than they are with paper.A LOM variant called ultrasonic consolidation (UC) or ultrasonic additive manufacturing (UAM) deals exclusively with metals. Popularized by metal AM company Fabrisonic, the UC process creates ultrasonic vibrations to fuse the metal sheets, typically using a CNC mill rather than a laser to cut shapes in each layer. [4]<h3>Plastic</h3>Polymer sheets are another possibility for LOM printers. However, use of polymer sheeting instead of paper reduces the environmental friendliness of the technology.<h3>Composites</h3>Researchers and companies have successfully used LOM systems to print polymer-based composites reinforced with materials like carbon fibers and ceramics.<h2 id="isPasted">Applications of Laminated Object Manufacturing</h2>Laminated object manufacturing is not a like-for-like replacement for other 3D printing techniques, but it is highly suited to a handful of applications.In the area of rapid prototyping, LOM represents an affordable route to prototypes of various shapes and sizes. Though not as dimensionally accurate as other additive processes, LOM can be used to fabricate visual prototypes for business proposals, demonstrations, color matching, and other purposes. LOM systems may be appealing for companies that want to carry out in-house prototyping within an office environment.The ability to colorize paper LOM parts makes the technology suitable for full-color models such as marketing props, toys, and “3D printed selfies.” Color 3D printing, which is useful for both decorative and functional objects, has historically been dominated by processes like PolyJet 3D printing from Stratasys. Some color models may have to be printed on a larger-than-usual scale due to the low level of dimensional accuracy offered by LOM.Paper LOM 3D printing is an excellent means of making architectural models, which have traditionally often been made by hand from balsa wood. Laminated paper offers similar material characteristics to wood, but digital fabrication using LOM is much faster and more accurate than manual model making.Manufacturers carrying out sand casting or investment casting can use LOM to make sacrificial patterns. [5] An engineer can design a 3D object using CAD software, print it in paper using LOM hardware, then build a sand mold around it. The paper pattern can then be burnt out, creating a cavity within the mold, and the casting material can be poured in.<h2 id="isPasted">Pros and Cons of Laminated Object Manufacturing</h2>Laminated object manufacturing offers some highly desirable benefits, including affordability, a large printing envelope, and usability in offices. It also has its drawbacks, such as low accuracy and certain geometrical limitations.<table style="width: 100%;"><tbody><tr><td style="width: 50.0000%;">Pros</td><td style="width: 50.0000%;">Cons</td></tr><tr><td style="width: 50.0000%;">Paper feedstock more affordable than typical 3D printing materials</td><td style="width: 50.0000%;">Less dimensionally accurate than most 3D printing processes</td></tr><tr><td style="width: 50.0000%;">Machines can be operated in non-industrial environments</td><td style="width: 50.0000%;">Complex internal geometries difficult or impossible to achieve, since material must be manually removed</td></tr><tr><td style="width: 50.0000%;">Potential for colorization</td><td style="width: 50.0000%;">Few companies developing hardware; possibility of obsolescence</td></tr><tr><td style="width: 50.0000%;">Can fabricate large objects with open build area</td><td style="width: 50.0000%;">Hardware more expensive than FDM</td></tr><tr><td style="width: 50.0000%;">Can fabricate overhangs, since preceding layers of material act as a support</td><td style="width: 50.0000%;">Paper parts can absorb unwanted moisture unless carefully treated with sealant</td></tr><tr><td style="width: 50.0000%;">Can create composite laminates by alternately layering one material then another</td><td style="width: 50.0000%;">Few users worldwide, making it difficult to find online tips and solutions from other users</td></tr></tbody></table><h2>Conclusion</h2>Laminated object manufacturing occupies its own space in the 3D printing landscape. The process provides advantages that are difficult to find elsewhere, and its ability to print 3D objects from paper makes it one of the most environmentally friendly 3D printing options.Companies that need a low-cost, low-maintenance rapid prototyping solution might find LOM to be a perfect fit. The process is certainly hard to beat when it comes to making quick visual models. On the other hand, companies investing in their first 3D printer might consider LOM a riskier proposition than a process like FDM, since the overall number of hardware developers and users is low.Looking forward, paper 3D printing may well remain a niche concern, but LOM-adjacent additive manufacturing technologies like ultrasonic consolidation could become powerful tools in the modern factory.<hr><h2>References</h2>[1] Wohlers T, Gornet T. Viewpoint: History of Additive Fabrication (Part 1). Time-Compression Technologies. (March/April 2008).[2] About Us • CleanGreen3D [Internet]. CleanGreen3D. 2021 [cited 2021Oct25]. Available from: https://cleangreen3d.com/about-us/&nbsp;[3] LOM (Laminated Object Manufacturing): 3D printing with layers of paper [Internet]. Sculpteo. [cited 2021Oct25]. Available from: https://www.sculpteo.com/en/glossary/lom-definition/[4] Technology [Internet]. Fabrisonic. 2018 [cited 2021Oct25]. Available from: https://fabrisonic.com/technology/&nbsp;[5] Chang K-H. Rapid Prototyping. In: Chang K-H, editor. e-Design. Cambridge, Massachusetts: Academic Press; 2015. p. 743–86.

Laminated object manufacturing (LOM) is a unique rapid prototyping process that combines additive and subtractive elements. This article explores its characteristics, benefits, and applications.


Laminated Object Manufacturing: Creating Strength With Layers

Actuators are an integral part of instrumentation systems that power the machines that exist today. These devices make it possible for the machines to interact with their surroundings the way they do. In this article, we take a closer look at the omnipresent technology.

Technical Guides

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Resin vs Filament 3D Printers: Pros and Cons of Curing and Extrusion

3D Printed Aluminum: Everything You Need to Know

Laminated Object Manufacturing: Creating Strength With Layers

What is an Actuator? Types, Principles, and Applications