The Elegoo MArs Pro offers incredible results from a small desktop form factor. But resin printing isn’t for everyone–it can be messy, and dangerous.
- Brand : Elegoo
- XY Resolution: 2160×1140
- Build area: 120x68x155mm
- Light Source: 50W UV 28 LED matrix
- Layer Thickness: 10 microns
- Printer Size: 195x195x405mm
Looking for one of the best resin 3D printers? The Elegoo Mars Pro offers cutting-edge MSLA technology, a carbon filter for toxic fumes, and premium build quality for around $300. For its level of detail and quality, it’s one of the best printers for those who want to produce small-format miniatures or models.
Join us as we take a closer look at the Elegoo Mars Pro, and at the end of this review, you’ll find a giveaway where you can win one for yourself!
Before explaining why the Mars Pro is a great resin 3D printer, it’s worth asking if you really need a resin printer.
SLA Resin Printers vs. FDM printers: Which Is Right for You?
Resin printers produce foul-smelling fumes, carry unknown health risks, and require tedious cleanup of unused resin. But the tradeoff is that you can pump out stunning and intricate 3D models.
But because of the health risks associated with ultraviolet-sensitive liquid resins, SLA printers aren’t for everyone.
What Is an MSLA Printer?
Masked Stereolithographic (MSLA) printers differ from regular SLA printers in a simple, but elegant, way: there’s an LCD screen that functions as a masking layer between the resin-hardening ultraviolet (UV) curing lights. The LCD mask controls how light hardens the resin. It even uses anti-aliasing or smoothing of 3D models, in order to deliver streamlined curves that not even the best FDM printers can match. Unfortunately, MSLA printing suffers from the same problems that all resin-based printers have. They smell terrible.
Resin Printers Smell Terrible, But the Mars Pro Less so
Resin printers smell something awful. Whenever you’re pouring or printing, there’s a malingering chemical odor. We’re not talking about the smell of fresh vinyl or new car smell. We’re talking something that smells like it’ll give you cancer. Whether it’s actually carcinogenic isn’t well understood by medical science.
Are 3D Resin Printers Safe?
There are few studies on the safety of 3D resin printers. While some argue that the fumes are perfectly safe, others claim that the liquid resin can cause allergic reactions, if left on exposed skin.
In my own experience, liquid resin isn’t something children should use or be exposed to. Shortly after printing out several models, a small amount of liquid resin got onto my right hand. For about a week following the exposure, I experienced shooting pains, similar to an arthritic episode. I can’t say with certainty that the resin caused the pain, but it’s worth mentioning that resin printing is messy and its health consequences, if any, are unknown.
At the very least, you must wear nitrile gloves, work in a ventilated room, and avoid direct contact of the resin with your skin.
Elegoo Mars Pro 3D Resin Printer
The Elegoo Mars Pro on paper offers the state-of-the-art in resin printing technology in the $300 price range. While its physical dimensions are the smallest of all similar printers in its price range, it still manages to squeeze in the same resolution and build volume as its competitors, with an advertised faster print speed, thanks to its array of 50-watt ultraviolet LED curing lights. Some of its standout features include:
- Front-facing USB-A port
- Print volume of 120x68x155mm
- 2K (2160×1440) resolution of 0.047mm per layer
- New MSLA technology
- Activated carbon filter and fan for removing toxic fumes from resin printing
- Grained build plate for better print adhesion
- Automatic bed leveling
- 28 UV lights at 405-nanometer wavelength rated at 50-watts per LED
- Minimum layer height of 0.01mm (10 microns)
- Chitubox 3D Slicer software
- Body dimensions of 195x195x405mm
- One-year warranty
- Comes with a MyMiniFactory membership
- 5% faster than the original Mars printer
- MSLA (Liquid Crystal Mask Stereolithography, or Mask SLA) printing technology
- Solidly built; excellent construction quality compared to cheaper products or DIY kits
Overall, the Mars Pro is a great device, comparable to its competitor, the Creality LD-002R in almost every way, with just a few exceptions.
Easy Assembly and Setup
Like most resin printers, the Mars Pro arrives mostly assembled. Users only need to attach a rubber valve around the base of the hood, screw the print bed into the vertical rail, and then load the resin. The bed leveling process isn’t difficult, either.
Unfortunately, the instruction manual included an error. It mentioned that the first step is to “move the Z-Axis position to zero”.
The correct first step is set the Z-Axis to Home. To do so, press the Tool > Manual > Home button. Fortunately, while the text itself is false, the images in the instruction contain the correct set-up steps.
The bed leveling process is the same as other resin printers. Users simply loosen up the attachment screws that connect the build plate to the Z-axis arm, drop the plate down to the base of the printer, and then use a piece of paper to set the appropriate distance from the plate to the base. You then tighten the screws of the build plate and then home and zero-it out. It takes about five minutes to calibrate it properly. And if it turns out that your prints don’t adhere to the plate or they rip off the plate too easily, you can make minor manual adjustments by moving the Z-Axis up or down.
The most difficult part of making a resin print is using Chitubox. While Chitubox is great, the problem is that the default Mars Pro settings didn’t work. None of the supports held during the early stages of the print process and so the models split apart, with half stuck to the build plate and half stuck to the tank. Fortunately, increasing the support density in Chitubox led to the model’s support not breaking. Unfortunately, I learned that 100% support density leads to solid, unremovable supports. In general, just a 10% increase in supports was enough to keep models from falling apart.
I reached out to Elegoo customer support explaining that my model continued sticking to both the build plate and the resin tank, causing the model to break off at the supports. Elegoo explained that I would need to increase support density rather than increase the lower-layer exposure times.
Printing 3D Models With the Elegoo Mars Pro
After rendering a model with Chitubox, you’re ready to print. The process is exactly the same as with an FDM printer, with one exception: resin-printed supports are trickier to pull off. Because resin is more brittle than PLA plastic used in an FDM printer, pulling off supports often can break the model itself. This is why there is a fine balance between setting support density in Chitubox and whether or not your print sticks to the build plate.
I found that larger models require a slightly 10% increase in support density. And that many miniatures stick to the plate better by removing all initial layer supports. Unfortunately, once you’re doing printing, you’ve got to clean up a smelly, sticky, poisonous mess.
Resin Cleanup Is a Smelly, Pain-Staking Affair
As with all resin printers, the worst part is cleaning up after a print, particularly a failed print. And all my early prints failed.
Cleaning a Mars Pro printer requires straining excess resin using a special funnel/filter to remove hardened plastic. You then need to wipe the tank and tray down and spray them with a 95%+ alcohol solution. If there are any chunks of print clinging to either surface, you must remove them using a scraper. The smell is atrocious and many report suffering headaches when in the same room as a resin printer.
Because of the nature of working with liquid resin, it’s also hazardous, particularly if you aren’t familiar with resin printers.
After Finishing the Resin Print
The most wasteful and irritating thing about printed resin models is that they require cleaning in order to remove the remaining liquid resin. Resin prints should only be handled in well-ventilated areas. Furthermore, you should take great pains to clean residue. The cleanup process requires that an alcohol solution of 95% be used to wipe the models down, removing liquid resin.
Many online tutorials recommend a bath in methylated spirits in a special sealable container. But in my experience, even long baths in alcohol do not fully remove residual resin from models. You would need to scrub each model with a brush in order to get most of the resin off. Because of the difficulty in cleanup, I can’t recommend resin printers unless you absolutely need such a fine level of detail in your models.
Another issue is the cost of printing. Liquid resin per kilogram costs twice as much as filament.
Elegoo Mars Pro Vs. Creality LD002R: Best 3D Resin Printer Under $300?
If you’re looking for the best $300 resin 3D printer, the Elegoo Mars Pro, and Creality LD-002R are nearly identical. However, there are a few features that distinguish each from another.
External Power Brick
The Mars Pro uses an external power brick compared to the internal power supply on the LD-002R. External bricks allow for a smaller printer and are more modular. If the power supply ever breaks, you can replace it with a standard 72-watt unit. A replacement external power brick also costs less than the internal power supply inside of the LD-002R.
Better Fume Sealing
The Mars Pro includes a rubber sealing ring around its UV hood, which improves its odor emissions.
Front-Facing USB-A Port
The Mars Pro’s USB-A port is on its face, making it easier to access. Creality’s is located on its side.
50-Watt Ultraviolet LED Lights
Elegoo claims that the Mars Pro has 50-watt ultraviolet LEDs which should offer 25% faster print speeds. However, in my estimate, the print speed is about equal to Creality’s LD-002R.
Harder to Replace Carbon Filter
The biggest failure of the Elegoo Mars Pro is its lack of an easy-to-access removable panel for its carbon filter. As you can see in our review of the Creality LD-002R (which compares favorably to the Elegoo Mars Pro), the top-deck fan intake includes a removable grill.
On the Mars Pro, I can’t see any easy method of accessing the fan assembly. That means cleaning the fan and replacing the carbon filter may take more effort and disassembly steps. While there are no published guidelines on how often you should replace the carbon filter, a good estimate is somewhere around every six months if you use the printer frequently. HakkoUSA estimates that a carbon filter on a fume hood should be replaced every 640 hours of operation.
Sightly Quieter Operation
The Mars Pro’s exhaust fan is placed at the bottom of the unit, rather than on the side. This allowed Elegoo to use a larger, slower, and quieter fan than Creality.
A minor point of concern is some of the soldering work and a stripped screw. I can see from one of the daughter boards that there are two instances where the solder was not properly flowed. And on the screws connecting the LCD to the chassis, one screw was stripped, which would complicate removal and replacement of the LCD panel.
I’ve seen plenty of stripped screws on other 3D printers though, and while this isn’t terrible, it’s not great either.
Warranty and Customer Service
Despite claiming a year-long warranty on Amazon, Elegoo terms-of-service page specifically states that it doesn’t offer a warranty. Here’s their official warranty policy:
The Service is provided to You “AS IS” and “AS AVAILABLE” and with all faults and defects without warranty of any kind.
Fortunately, Elegoo offers part replacement. For example, if you experience an issue with your printer and their customer service determines the hardware is faulty, Elegoo will ship you the damaged component. It’s up to users to replace the part, however. Fortunately, 3D printers are easy to disassemble and reassemble.
Having experienced issues with the Mars Pro, I reached out to Elegoo through email, which is their only customer service method. But I sent two emails and received responses within 24-hours. The emails were clear and included generic troubleshooting tips. After applying the troubleshooting tips, I managed to get back to printing within an hour.
The warranty policy is about equal to its competitors.
It’s also worth mentioning that if you decide to return an Elegoo product, you’re responsible for paying return shipping to China. Unfortunately, on an item as heavy as a 3D printer, the shipping cost is almost as much as the printer itself.
Reasons You Might Not Want the Elegoo Mars Pro
Unfortunately, the Elegoo Mars Pro isn’t for everyone. It has a few of the drawbacks of a resin printer, along with:
- The build plate size is only suitable for very small prints.
- The set-up documentation contains an incorrect step and is sometimes unclear because of translation issues.
- The carbon filter does not appear to be easily replaceable. There is no guidance on how to replace the filter from the manufacturer and I could see no easy way to do this from a quick disassembly.
- There are soldering flaws on one of the daughter boards and other minor workmanship issues.
- One major design flaw is that the fume fan lacks a filter-cover and sucks in air through its top, rather than through a less exposed area. Unfortunately, chunks of hardened resin can get sucked into the fan assembly. Additionally, there’s no easy way to disassemble or clean the fan.
Should You Buy the Elegoo Mars Pro Resin 3D Printer?
The Elegoo Mars Pro offers 3D resin prints in the 120x68x155mm form factor, without skimping on build or print quality. It’s comparable to Creality’s LD-002R, with better fume sealing and quieter operation. I recommend it to hardcore miniature users, such as wargamers and RPG-players, who want pristine and nearly perfect models.
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