What are the best SLA 3D printers

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3D printers with DLP technology impress with their grandiose print resolution and massively fallen prices. We show which printers are worth buying from.

For tabletop figures or other small and highly detailed printed products, 3D printers that work with viscous resin are much more suitable than the widespread and even cheaper devices with filament melting technology (FDM). The reason is the very high print resolution; but you have to deal with smelly chemicals. Those who are not afraid of working with liquid resin and isopropanol can get printers suitable for beginners from 140 euros.

DLP stands for Digital Light Processing, such printers work according to a simple principle: A UV light source exposes liquid resin through a high-resolution display and hardens it in layers in the desired places. At 0.01 to 0.2 mm, the individual layers are so thin that they can hardly be seen with the eye. For comparison: Inexpensive FDM printers build models from layers between 0.1 and 0.4 millimeters of molten plastic.

The first available printers such as Elegoo Mars (test report) or Anycubic Photon (test report) use an inexpensive RGB display for exposure. The disadvantage of these displays is their short service life of just under 500 operating hours and the fact that a lot of UV light is absorbed. The exposure time for standard resins is around 6 seconds with a layer thickness of 0.05 mm. Current models, such as the Anycubic Mono X (test report) or the Elegoo Mars 2, on the other hand, work with a monochrome display. This enables a significantly shorter exposure time (1.5 to 2 seconds at 0.05 mm layer height) and is significantly more durable (approx. 2000 hours).

The catch with this printer variant: the installation space is comparatively small, so you cannot print large models. In addition, handling resin and cleaner is annoying and the printing material is more expensive than the filament rolls for FDM printers.

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Branded product or unknown manufacturer

There are only two well-known branded products in our list of SLA printers. The reason for this is the extreme price difference and the very similar features, at least on paper. At over 1000 euros, printers from Xyzprinting or Formlabs are many times more expensive than the cheap China models. As our test of the DLP printer Elegoo Mars (test report) shows, cheap doesn't have to mean bad. The 180-euro model surprised us positively, and the annoying handling of the resin is not yet completely relieved by the 1000-euro range.

The manufacturers have reacted and so there are now semi-automatic washing stations for cleaning. The already tested model Anycubic Wash & Cure-Station (test report) makes work a lot easier. However, this solution is too small for the relatively large print objects of a Mono X.

The affordable SLA printers for private users all come from mainly Chinese manufacturers such as Anycubic, Elegoo, Creality, Wanhao, Longer or Sparkmaker. Those who have already dealt with FDM printing know at least a few names of it. As is so often the case with China goods, some of the devices are also available under different product names. The Sparkmaker, for example, also appears in the price comparison under the name Fesjoy.

The following overview shows a large part of the SLA printers currently available in Germany in the entry-level and mid-range segment. Some models cannot currently be found in the price comparison because they are not marked for the German market, for example. If you are looking for something, you will find corresponding offers at Chinese shops such as Banggood or at Amazon dealers. These include, for example, new models with monochrome displays such as Anycubic Mono, Nova 3D Elfin 2, Nova3D Bene 4. The Elegoo Saturn is also only available in theory so far, as the previous offers were sold out after a few hours.

The maximum size of the print products with SLA printers is significantly smaller than with filament printers. The affordable model, the Anycubic Photon Zero, has a maximum size of just 95 × 54 × 150 mm. The Wanhao Duplicator D8 has more space at 190 × 120 × 180 mm, but it also costs significantly more. The same applies to the Anycubic Mono X (test report).

This cannot keep up with the average space available for FDM printers (between 200 × 200 × 200 mm and 400 × 400 × 400 mm). But is bigger automatically better? Ultimately, that just depends on what is to be printed. A small installation space is sufficient for model making accessories or tabletop figures, but if you want to print a pretty vase for the living room table or cutlery inserts for drawers, you won't get very far.

Print quality and speed

The layer thickness (z-axis) and the resolution of the display panel installed above the UV light source are decisive for the print quality. The layer thickness determines how long the printing process takes and how filigree the result looks along the z-axis. Print products with layer height look better, but take more time. Prints with thick layers are finished faster, but the gradations can then be clearly seen. In practice, SLA technology is also about a good compromise between print quality and time. From our own experience, a layer thickness of 0.05 mm is recommended. Our tests with the Elegoo Mars look great; the time required is manageable. The printing of the chess pieces on the USB stick (1000 layers with a layer thickness of 0.05 mm) takes just over four hours.

If you want to be particularly flexible with the layer thickness, you should take a closer look at the devices from Anycubic, Elegoo or Sparkmaker. Their finest setting allows the printing of layers with a thickness of just 0.01 mm, but also layers with a thickness of up to 0.1 mm.

The resolution of the exposure monitor is responsible for the level of detail on the x and y axes. The higher the resolution, the finer the details. While the Anycubic Photon Zero and the Longer3D Orange 10 only have a resolution of 854 × 480 pixels, the Sparkmaker FHD, for example, has a panel with 1920 × 1080 pixels. The popular printers Anycubic Photon, Elegoo Mars or Longer Orange 30 (test report) use screens with a resolution of 2560 × 1440 pixels. The new models with larger installation space, such as the Anycubic Mono X (test report), even use a 4K display with 3840 × 2400 pixels.

While this information is easy to find with the China manufacturers, the brand manufacturers are silent about it. Our inquiries about this have so far remained unanswered; the hotline couldn't help either. As soon as we have the information, we will add it.

The maximum printing speed of most SLA printers is between 20 and 40 mm / h in height. Models with a monochrome display are, at least in theory, much faster. In practice, however, this is only noticeable with thick layers and thus reduced quality.

The following time-lapse video shows what printing looks like with a resin printer.

Like most inexpensive SLA printers, the Elegoo Mars works with a wavelength of 405 nm and therefore also works with any resin that cures at this wavelength. This includes, for example, that of Anycubic. The prices for the consumables start at 25 euros for 500 ml. Brand manufacturers like Xyzprinting charge more than twice as much. The manufacturer even prevents the use of third-party resin by querying NFC tags. But those who keep their eyes open regularly get good bargains. For example, the standard resin from Elegoo is regularly available from Amazon for 19 euros per liter. The normal price is around 35 to 40 euros.

To illustrate: With the SLA printing process, just under 16 ml of resin are required for the well-known Benchy ship model. With the resin from Elegoo, the boat costs around 80 cents. With the resin from Xyzprinting, the cost of the model is over 1.60 euros. For comparison: the FDM print with filament weighs just under 15 g, which results in material costs of just 15 to 30 cents.