Makers Empire spends a lot of time testing various 3D printers from different companies. This lets us build up a database of printers and assess their suitability for primary schools. You can view our Best 3D Printers for Australian Schools and our Best 3D Printers for American Schools guides. Until now, though, these printers have all been FDM (Fused Deposition Modelling) – essentially, a computer controlled hot-glue gun.
In the past month or two, we’ve been testing a new MSLA (Masked Stereolithography) resin printer. People often refer to MSLA printers incorrectly as DLP (Direct Light Processing) printers but they are not the same. Before we get any further into this review, I’ll explain what this means.
Below you can see three of the most common resin printing techniques:
- Laser SLA uses a laser beam to draw the outlines and infill of each layer, similar to the nozzle on an FDM printer.
- DLP-SLA uses a projector to project a shape of light into the resin.
- MSLA has a UV light source which it projects into the resin, however, the layer shape is ‘masked’ via an LCD screen, similar to painting through a paper stencil.
So now that we all know what and how this resin printer works, let’s learn more about it. This new resin printer is from a company called Weistek based in Shenzhen, China. They’ve been making 3D printers for a while now, and we’ve tested and reviewed some of their older machines. Makers Empire works with Weistek in China and this printer was provided to Makers Empire by Weistek for the purposes of testing and potential review.
- Printer Type: MSLA
- Build Area: 192mm x 60mm x 120mm (HxDxW)
- Build Volume: approximately 1,300ml
- VAT Volume: approximately 120ml
- Maximum Resolution: 0.05mm layer height
- X/Y resolution: 0.042mm (that’s 24 pixels per millimetre!)
- Weight: 6kg
We’ll need to slow down for a second, and talk about materials for this resin printer. While FDM printers have filament that goes into the top of the extruder, resin printers are a little more complicated as they require a liquid resin.
We’ve been using a plant-based resin which cures when it’s exposed to UV light, which is what the printer produces. You can get these resins in a variety of colours, textures, materials and even mix colours together to get custom colours.
We mixed red and blue, to make some purple/pink prints. You can also get advanced resins that are super strong, conductive, flexible, castable and more. These resins cannot be exposed to UV light or the sun, otherwise they’ll start hardening. Thankfully they are shipped in brown bottles that stop sunlight from getting in.
The next thing to look at is the printing process itself. There’s a few types of ‘resin printers’ but this new Weistek model is a ‘MSLA’ printer. That stands for ‘Masked Stereolithography’. Essentially it uses an LCD screen to draw out each layer, and shines a UV light through the screen to cure a thin layer of resin onto the build plate.
The support structures are even different in a resin print. Because this printer is printing things upside down, it needs to account for the increasing weight of the printed model as it goes. This means that your supports at the start need to be strong enough to actually carry the entire thing. It’s a fine balance between having supports that are strong enough, and making sure they’re still easy to remove. Once you have support settings correct though, you tend not to have many failed prints.
One of the little quirks about resin printers is that there is actually a maximum print time. Each layer needs a given amount of time to cure, and you can only have so many layers within the build volume. Each layer is 0.05mm thick, the time for curing and resetting each layer is 14 seconds, meaning the maximum print time is 14 hours, 56 minutes. This is, however, restricted by the amount of liquid resin that the print vat holds.
Unfortunately, it only holds about 120ml, whereas the build volume is over 1.3 litres. For printing anything larger than 120ml, you’ll just need to keep topping up the vat as it goes.,
Print results from this printer are phenomenal. The standard layer height on this printer is 0.05mm, but it can go down to even 0.025mm. That’s around 4 times smaller layer heights than most FDM printers.
Below you can see a highly detailed print, where the ear and even the fingers look fantastic.
Here you can see a tiny hexagonal hole in the side of this part has been printed with no issues.
Below you can see a cross-comparison between one of the resin prints, and one printed on our Inventor IIS printers. The print from the Inventor IIS (the dark blue print) took about 6 hours, whereas the print from the resin printer (the light blue print) took around 11 hours.
One of the last things I tried before wrapping up this review was printing in some ‘clear’ resin. While I’d call it ‘transparent’ more so than ‘clear’, I was still impressed with how it came out. Below you can see a small cup, and a chess rook that I am pretty happy with.
- Phenomenal print detail using individual pixels.
- Ability to print very small models.
- Printing multiples doesn’t add print time.
- Low risk print process (the worst that can happen is for resin to stick to the bottom of the vat).
- Messy to use. You’ll need a sacrificial layer (e.g. cardboard) under the printer and work area, plus an apron, gloves and safety glasses. A respirator is also helpful to avoid fumes from the clean-up chemicals.
- Small build volume.
If you’re looking for fantastically smooth and detailed 3D prints then I’d recommend this resin printer.
The plastic chassis really doesn’t affect the printer in any way, and the print results speak for themselves. The ability to print in a range of third party resins is also a nice bonus over some manufacturers that lock you in to using their own brand of resin.
The downside is the mess, the smell and the chemicals needed to operate these types of printers.
If you’re happy to push through these factors, you’ll be rewarded with amazing prints.