How to Choose a 3D Printer?

Technology and application

3D printing has a wide array of applications. Some of them require special printers, able to print from metal, biomaterials, or with a huge print volume. We are going to focus just on regular, “desktop” printers, affordable for an ordinary customer. However, that doesn’t mean such printers are only suitable for simple tasks and hobby purposes. On the contrary, many of them are frequently used for business, in science, or medicine, sometimes even arranged into print farms, i.e. dozens or even hundreds of printers together.

Keep in mind there are many differences even among this category of printers. For various applications, some options might be more suitable than others. Later in this guide, we will also mention some factors you should take into account if you plan to use your printer professionally (or basically for any heavy-duty purpose).

By the way, if you don't have any particular use in mind yet, and just think 3D printing sounds fun, do not worry. There is plenty of inspiration available on the internet, as ready-made 3D models for download. Of course, the process of choosing the right printer is going to be a bit more difficult if you don’t have clear preferences yet.

Before we delve deeper into this topic, you should choose which of the two popular 3D printing technologies is more suitable for you, as the differences can be significant:

FFF (sometimes called FDM) technology prints from a melted plastic filament, extruded from a nozzle. Imagine a large and very precise hot glue gun, carefully layering the material, that is quickly cooled down to form a solid object. It is by far the most popular 3D printing technology. 

Its main advantages are a larger print volume, easier use, and manipulation with the print material (filament) - which is available in many different colors and materials with various functional qualities.

The main disadvantage is visible print layers, which might be bothersome, especially on small and detailed prints.

SLA technology (also called MSLA or DLP - more on the terminology later in the chapter on SLA printer construction) prints from a liquid resin, hardened by a UV light source. 

The main advantage is the ability to print much smaller and more refined details than the FFF technology. The newer SLA printers are also very fast.

The main disadvantage is a smaller print volume and more difficult manipulation with the print material (sticky liquid, often with unpleasant odor). Fresh prints need some additional care - first, the uncured resin has to be washed away, and then the prints need more UV light exposure to cure completely.

More information on the basic terminology is available for example in our e-book Basics of 3D Printing. It’s available here for a free download.

SLA and FFF technology are very different from each other, therefore, we will consider them separately first. In the last few chapters, we will go through some aspects common for both technologies (price, technical support, etc.).

Choosing an FFF printer

FFF printer construction

Each FFF printer has two basic components: a print head with a nozzle that extrudes the melted filament. The extruded material builds up, layer by layer, on a print bed.

The FFF technology has more subcategories, each of them having different means of moving these two components against each other. By far the most common is the cartesian construction: the print bed usually moves forward and backward, the print head moves above the bed, sliding on vertical and horizontal axes, up-down and left-right. There are other construction types as well (named delta, corexy, polar, etc.), that have completely different patterns of movement: for example, the print bed might be static, rotating, or moving up and down.

We won’t discuss the different constructions and their pros and cons here, as it is a complicated topic worth a standalone article. At least a basic description is available in our e-book Basics of 3D Printing. If you don’t want to study this topic in detail yet, don’t worry, you can choose your new printer just fine by considering other parameters.

As for the print bed, it can be manufactured from various materials, for example from glass, but modern printers usually have a removable steel sheet with a special coating. Print bed heating is a very important feature.

As for the print head, there are two main construction variants. The first variant is called direct or direct drive, where the drive gears responsible for pushing the filament into the nozzle are located directly in the print head. The whole print head is then usually called the extruder. The second variant is Bowden, where the drive gears are placed separately (in a component called extruder). This results in a lighter print head. The filament travels between the extruder and the print head through a Bowden tube.

As for some “premium” FFF printer features, let’s mention for example:

• filament sensor, if the printer runs out of filament, the sensor lets you insert a new spool before resuming the print. Without the sensor, the printer would just continue printing empty, resulting in a failed print.
• “power panic”, i.e. protection against power loss (adds the possibility of resuming the print when the power is back on)
• various means of remote control of the printer (wifi, bluetooth, etc.)

Obviously, the appearance of the printer is going to impact our decision, the same as with any other product. Try to distinguish purely aesthetic factors from those that affect the printer’s function and ease of use. For example, a closed design (the whole printing mechanism is inside an enclosure) looks more professional, which often means more expensive (but often with worse value). However, the closed design does have an actual impact on the print quality, when printing large objects and/or special materials, because it helps maintain a stable temperature. The open design looks more “DIY”, but also makes accessing the printer’s mechanism much easier, for maintenance or possible mid-print interventions.

We will give you more examples of how the various features mentioned above affect the printer’s speed, print quality, etc., in the following chapters. 

By the way, you can customize your printer’s appearance and give it a really personalized look. If the printer is open source, usually, there are printable parts available, with various modifications shared by the community.

Print material (filament)

Now let’s look at the printer features from the aspect of print material. 

• Special materials are usually harder to print with. One of the factors is the minimal necessary nozzle temperature. In most cases, you need to reach temperatures of 200-300 °C (392-572 °F). Make sure your printer is able to meet the requirements of the materials you are planning to use.
• For most of the print materials, a heated print bed is also necessary. It decreases the risk of the printed object warping or even detaching from the print bed. The print bed surface also plays its role, as special coatings increase the adhesion.

• A closed design (enclosure) of the printer also helps to maintain a stable temperature. Even an “open” printer can be put into an enclosure, there are various DIY solutions for that, for example using a photo studio light tent, or an IKEA Lack table).
• The direct drive printers make printing of some materials (especially TPU/TPE, soft, flexible materials, often called just “flex”) much easier. These printers are also less prone to problems caused by a low-quality filament (that could get stuck in the bowden tube because of uneven diameter or bumps on its surface). On the other hand, bowden printers, thanks to a lighter print head, have more fluent movements and suffer less from vibration-induced print defects. Therefore, it is difficult to clearly say which construction solution is better.
• Some materials (for example those containing metal particles or carbon fibers) are abrasive - replacing a regular nozzle with a hardened one is recommended.

By the way, multi-color (or even multi-material) printing is possible with the FFF technology. There are various solutions, more expensive printers may have multiple nozzles or print heads (extruders).

To a certain extent, simple multi-color print is possible with almost any FFF printer - you just pause the print job and replace the filament manually. 

More information on various filament materials is available in our Knowledge Base.

Print quality

The topic can be split into these two aspects:

a) The level of “resolution”, i.e. how fine details is the printer able to render. This depends on the minimal print layer height and the nozzle diameter. Changing the nozzle (make sure this is possible with the printer of your choice) from the most common 0.4mm diameter to, for example, 0.25mm, will bring very noticeable improvement of details. However, it will also make your printer much slower - so the right choice depends on your priorities.

b) Absence of print defects, like shifted layers, uneven or “wavy” surface, etc. This is a matter of printer construction quality, both regarding the individual components and their assembly.  

• Some manufacturers claim awesome values of the minimal print layer height (as little as 0.02 mm), however, realistically, the results are also limited by the nozzle diameter and by the general character of the FFF technology (extruding hot plastic is never going to be absolutely precise).
• The choice of filament also affects print quality. Some materials don’t render details that well and/or are more prone to print defects.
• To maintain the initial advantage given by a well-built printer, regular maintenance is needed (tightening loose belts, lubricating bearings, updating the firmware, etc.) 
• 3D model optimization before printing helps a lot (even simple things, like how the model is oriented on the print bed, go a long way quality-wise).
• The appearance of the finished prints can be radically enhanced with post-processing techniques like filling, sanding, various methods of smoothing the surface, etc.

Print speed

• To a large extent, there is an indirect proportion between print quality and speed. For example, if you need simple prototypes or functional parts, you can sacrifice the details for quicker printing, by mounting a larger diameter nozzle (say, 0.6mm instead of 0.4mm) or by different software settings, for example, a larger print layer height.

• You can also directly increase the speed of the printer’s moving parts, however, this will also increase the risk of print defects. For example, faster movements will cause vibrations, filament won’t have enough time to cool down and harden, etc.
• It is difficult to compare different printers simply by stats given by the manufacturers unless you can see what quality can the printer achieve at that given speed. Also, the exact speed depends on a particular 3D model, as some printers might deal better or worse with certain shapes.
• In the end, the most effective way of speeding things up is, again, optimization before printing: not wasting time with printing unnecessary supports, too dense infill structure, etc. You can learn all the tricks later, for example from our online beginners’ courses.

Print volume

The option of large-scale printing is one of the main advantages of FFF technology.

However, when looking for a printer with a huge print volume, consider the following:

• With most materials, the maximum print size will be limited by warping caused by thermal differences between the print layers, anyway.
• Basically, the only material suitable for really large prints is PLA (i.e. the most common material, with average physical qualities - it is relatively brittle and not very heat resistant).
• To a large extent, the issues with warping can be reduced with a closed design (or placing the printer inside an enclosure), that maintains a stable temperature.
• The larger the printer, the more stable and well-built it must be to maintain print accuracy and quality.
• Usually, it is quicker (and also more reliable) to print large objects as multiple parts on more printers at once. The parts can be glued, snap-fitted, or screwed together afterwards. Therefore, the maximum print volume doesn’t have to be the most important factor when choosing your printer.

• Printing really large objects can take several days, a failed print then means a significant waste of time and material. There are two features worth gold in this regard: the filament sensor and power panic (power loss protection), both mentioned above.

Using the printer: noise, ventilation, necessary space

• If your printer will be placed in your office or living room, noise is going to be an important factor. FFF printers can be rather noisy, because of their ventilators, stepper motors, and all the movements along their axes. A good modern printer can have an average noise level of 50 dB, older or cheaper model 65 dB. It seems it’s not such a big difference, but it’s exactly over the threshold when we start to perceive the noise as really distracting when working on a computer, etc. The level of noise is also influenced by the printer settings and its maintenance (for example lubricated/worn bearings).
• Don’t forget that apart from the space occupied by the printer itself (with some leeway on all sides) you need some space for the spool holder and also for storing and manipulating all the material, tools, and finished prints.
• Some of the more advanced materials (for example ASA or ABS filaments) emit unpleasant odors during printing. Therefore, the printer should be placed in a ventilated room, but at the same time, not drafty (that would increase troubles with materials prone to warping, coincidentally, that also includes ASA and ABS).
• Keep in mind that even odorless materials (PLA, PETG) might emit plastic microparticles - in a poorly ventilated space, these could reach harmful concentrations.

Choosing an SLA printer

SLA printer construction

All SLA printers print from a liquid resin hardened by UV light. However, there are multiple subcategories of this technology, depending on the source of the UV light and the way of its distribution (so the resin hardens only at the right place and moment). We will describe just one of those subcategories, the MSLA (Masked Stereolithography). To simplify things, we refer to it only as SLA. MSLA is by far the most common subcategory of all the SLA printers and many people perceive these names as synonyms. Again, a short description of some of the other subcategories can be found in the Basics of 3D Printing. 

The basic components consist of a tank filled with liquid resin. The tank has a transparent bottom, made of an FEP foil. Underneath the tank, there is a display, with a UV reflector beneath. The display projects silhouettes of the individual print layers on the FEP foil, these act as masks letting the UV light through only where necessary. A platform travels up and down, submerging to the resin tank, so each printed layer sticks to it, detaching from the FEP foil at the same time, making the bottom of the tank ready for the following print layer. An illustrative picture is available in the Basics of 3D Printing. 

Better SLA printers also have a tilt mechanism - the print layers stuck to the platform are not detached from the FEP foil by a direct upward movement, but with a slight swing of the resin tank, which makes the process much more gentle and reliable.

Print material (resin)

• As for the printer compatibility, unlike with filaments, there are no temperature requirements, the only factor is a UV light wavelength, that causes that particular resin to harden. A vast majority of the available SLA printers (and thus the widest choice of resins) use the 405 nm wavelength.

• There is a relatively wide selection of resins with various physical properties, from basic (usually called “tough”), through flexible, high-tenacity types, to special materials used in medicine, jewelry making, etc. However, the overall choice is smaller than with filaments, resins have worse functional parameters in general (basic variants are quite brittle), and last but not least, resin costs at least twice as much per kilogram than filament.
• Multi-color or multi-material printing is not possible with SLA technology. 

Print quality

• Similar to the FFF technology, the main factor responsible for the detail quality is the print layer height setting. Another important factor is the display resolution.
• Some printers support anti-aliasing, a setting which makes the visible print layer edges smoother.
• Monochromatic display (that is slowly becoming a standard for all better SLA printers) renders sharper details. Also, it has much better longevity than a regular color (RGB) display.

• Despite being able to print much more delicate details, the SLA technology is surprisingly simpler than FFF, at least regarding the printer’s mechanics. Instead of complicated movements in all three directions, there is just a platform going up and down. Nothing has to be heated up, the print material doesn’t travel anywhere. However, to make a good SLA printer is not that easy, as the technology is much more sensitive to any minor errors and inaccuracies. In the end, the quality of construction plays an even bigger role than with FFF, to ensure pinpoint mechanical movements, uniform dispersion of the UV light all over the print area, etc.
• Again, the print quality can be enhanced by thorough preparation and optimization before printing, as for the 3D model orientation, placing print supports, etc. This preparation is more demanding than with FFF and there is a bigger risk of print defects or outright print failure.

Print speed

• First of all, the print speed depends on the choice of the print material. Various types of resin have different curing times (in the order of seconds per print layer). The basic resins of any brand need a similar time, but special materials might require twice as much or even more.

• UV reflector and display are also very important: the more UV light the reflector emits, and the more the display lets through, the faster the curing process is. Printing with a monochromatic display is much faster than with an RGB display (even 4 times faster!).
• Note that the total print time is affected also by the speed and efficiency of the mechanical movements of the printer (platform moving up and down and print layers detaching from the resin tank bottom). The earlier mentioned tilt mechanism helps a lot in this regard.
• Interestingly, because the whole bottom of the resin tank can be cured at once, the total printing time is given only by the printed object’s height, its width and length doesn't matter (as long as it fits into the print area, of course). Ten identical models would print in the same total time as just one.

Print volume

• The print volume size of affordable SLA printers currently matches the size of a tablet or a larger phone (plus approximately 15 cm of height). That means it is much smaller than with regular FFF printers.
• More affordable larger-volume SLA printers are slowly entering the market, however, there is not much competition on the market yet and some of these printers might have questionable value, with too many corners cut regarding print quality and reliability.

Using the printer: noise, ventilation, necessary space

• In general, SLA printers are quiet, only the ventilators and the platform movement might emit perceptible noise.
• Resins have odors, how strong and unpleasant depends on a particular type and brand. There are odorless (or rather low odor) variants, too. Better printers have an air filter, but don’t expect it to always be 100% efficient - ventilation is a must.

• SLA technology needs more working space around the printer. The finished prints have to be peeled off the platform, washed from uncured resin with isopropyl alcohol, and finally cured with more UV light. There are curing and washing stations available for some printers, which will make these tasks much easier.
• Make sure the printer has easy calibration and controls. 
• The platform and resin tank should be easy to remove - you will have to do this after (almost) every print. 
• Also, the display and the FEP foil should be easy to replace.
• Is the printer easy to clean in case of some resin spills (that will happen, sooner or later)? 
• Is the printer lid easy to open? Does it stay open on its own (not always the case with cheap printers)?
• Why do we list so many things that sound quite self-evident or not so important? Well, the thing is, dealing with liquid resin can be so tricky and annoying on its own, that you will really appreciate smooth operation with no extra complications caused by the printer!

Aspects common for both technologies

Safety

• The same as with any other electric appliance, there are strict safety regulations regarding cables, connectors, power source, etc. Especially the heating components of the nozzle and the print bed on the FFF printers must meet the highest standards, so they don't pose a fire hazard.
• Firmware is of the same importance as hardware. It should include various safeguards, especially against overheating. Even though it sounds absurd, there are certain cheap printers on the market with these safeguards intentionally turned off by the manufacturer (they have to be reinstalled by an update).
• However, we must add that part of the responsibility is always on the user, as for the regular maintenance - the same as with an automobile. For example, you have to check for loose or damaged power cables.

Technical support

• Of course, in the end, everything is breakable 🙂 Even a top-notch printer will need reliable, 24-7 technical support. 
• It is always better to be able to contact the manufacturer directly, instead of just a vendor.
• The printer should be user-serviceable to some extent (for example, you should be able to clean or replace a clogged nozzle yourself). Is there proper documentation and comprehensible manuals?  
• The user community is important. Keep this in mind when choosing an unusual/rare printer, you might have a hard time looking for advice later.
• Does the manufacturer support even its older printer models? Are there long-term firmware updates, bug fixes, hardware upgrades?

Professional use and/or frequent printing

Keep in mind that the most important quality of a (semi)professional printer is neither speed, superb details, or ability to print special materials, but simply its reliability. When you work with firm offers and deadlines, you can hardly tell your clients “sorry, my printer is just acting up today” or “I’ll have to charge you three times for material because I had two failed prints”.

• Are replacement parts readily available? How much do they cost? How quick a service repair would be?
• As even the most reliable printer breaks sometimes, consider splitting risks with two less expensive printers instead of one (of course, not sacrificing quality or reliability, but for example print volume), or one main printer and one smaller as a backup.
• The print preparation (calibration, preparing print bed) should be easy and not too time-consuming. Of course, this is important for all users, but twice as much if you print almost nonstop and have to meet deadlines.
• Easy controls also mean you can delegate the tasks to less experienced colleagues.
• Some options of printer remote control will be handy.

Price

This aspect is listed as the last one in this guide, on purpose - it makes no sense to consider price before you really make sure what do you need your printer for and what features and advantages it should have. 

• Make sure you know what you pay for - what features are you really going to utilize?
• Don’t forget the value of your time. When choosing between cheaper and more expensive options, it is often a question of what is more valuable for you: your time or your money. A working middle-aged person would probably see this differently than a student. Even a poor, low-quality printer can sometimes be tuned and upgraded into a half-decent machine, however, it depends on how much time and effort are you willing to invest. Sadly, in most cases, you’ll have to invest time and money, anyway, paying the cost of various upgrades and spare parts. In the end, you often spend even more, just with costs spread into a longer period.
• Note that, as with any other goods, sometimes you pay just for brand and design. There are printers on the market that cost more than 5000 USD and yet feature more obsolete solutions than printers sold for 1/10 of their price.
• You can save costs by choosing an assembly kit instead of a completely assembled printer. In such a case, you don’t have to make any concessions to quality, just do some work instead of the manufacturer. There is an added bonus, too - you’ll get to learn how your printer works, which will make later maintenance much easier. However, there is also some risk of defects caused by your own errors during assembly, therefore it is very important to choose a kit with good, thorough instructions.
• An interesting choice is picking multiple less expensive printers instead of spending the whole budget on a single machine. That means splitting the risks, and also brings an option of faster printing by splitting a large model into parts and printing them at once.
• Don’t forget the operating costs! It makes no sense to acquire an expensive printer and then feed it with a low-quality material. A cheap filament often causes clogging and various print defects. Also, keep in mind the extra cost of some special materials you might need for your projects.
• Avoid manufacturers that force their customers to use only their brand of material! Such filament or resin might cost multiples of the regular price. For example, a regular SLA printer resin is usually sold for 70-90 USD per kilogram. However, a resin of the same quality, sold in the form of a branded and chipped cartridge, costs more than 200 USD!
• A similar problem exists with spare parts. There is always a wider (and less expensive) choice for printers with an open source license.

Where to get further information?

As the amount of 3D printers on the market has grown, so did the sources of information. Here are just a few examples of popular Youtube channels and online magazines, where you can look for reviews and other 3D printer related content:

3D Printing Nerd

Thomas Sanladerer

CNC Kitchen

All3DP

3D Printing Industry

Make: Magazine

Now for some general tips from us:

• Obviously, it is optimal to rely on advice from someone you know in person, with verifiable 3D printing experience.  
• There are various workshops, labs, and maker spaces, where 3D printers are available for trying out.
• If you are considering a purchase of an Original Prusa printer, we suggest looking at a map on the PrusaPrinters.org website. You can find users in your vicinity who could help you or even show the printer at work (on the map, you can filter those offering “Show and Tell“).  
• As for the information from the manufacturer himself... obviously, everything they (or, we :-)) say could be just marketing a should be taken with a grain of salt. On the other hand, manufacturers are responsible and accountable for giving accurate information regarding technical specs, compatibility, etc.

There is a worldwide 3D printing community, made of people always eager to help. However, when sifting through all the advice, consider the following:

• Are the sources really independent and unbiased? (even with no selfish intent, someone is just an avid fan of a certain brand, etc.) 
• Do they really own that particular printer, did he try it, just theoretically consider trying it, or just repeat the opinions of somebody else? 
• How long do they own the printer? (People are most eager to share advice in euphoria just after they made their own purchase, without experience about the long-term reliability of the product, etc.)
• Have you seen their prints? (Quality is relative, what someone describes as perfect might be unacceptable for someone else.)
• “The XY printer is the best for learning the basics!”. XY usually stands for some dubious printer that needs tweaking and/or replacing most of its parts before the first successful print or hitting it with a hammer, whatever comes first. We believe that for efficient learning (unless you want to learn frustration tolerance), it’s better to choose the exact opposite: a decent, reliable printer, that lets you discern your own mistakes from the faults of the hardware, and doesn’t make you hate 3D printing right from the start... 🙂
• Another peculiar kind of advice goes like “you can buy this printer, but it won’t be any good unless you immediately replace the rods, the bearings, the firmware, use my excellent slicer profiles, etc.” Tweaking your printer is a lot of fun, for a lot of us, it’s actually more important than printing itself 🙂 However, it’s not a good idea to do it right from the start. First, give a chance to the factory settings and original components, before looking for their improvement. After all, if the printer comes from a decent manufacturer, these settings were probably tested on a much larger scale than any single user could do.