Elegoo Saturn 4 Ultra Review: Huge Innovation in Resin 3D Printing

I have to admit, before testing the Saturn 4 Ultra, I had gotten bored with resin printers. It seemed that manufacturers didn’t know how to meaningfully improve the system without burdening the user with specialty resins and costly consumable parts. Elegoo has realized that they don’t really need to make their printers bigger, faster or with more resolution. What we need is a printer that’s easier to use.

The Saturn 4 Ultra delivers, with fast and crispy 12k prints using ordinary resin and the same PFA films we’ve seen on Saturn’s for years. The improvements are within the machine itself – it has auto leveling with built-in sensors, a print monitoring camera that can also shoot time lapses, and a vat that gently peels each layer off the film by tilting.

The vat isn’t the only thing that tilts, so does the hood. The hood – which protects the uncured resin from ambient UV exposure – is on a hinge that can be tilted back with one hand. No more grabbing the lid with two hands and trying to find a place to set it down. This may seem like a small detail, but it’s a huge help, especially when you have limited work space. 

Launching with a pre-sale price of $399 on Elegoo’s site, the Saturn 4 Ultra is an excellent deal for a high resolution, mid-size printer and one of the best resin 3D printers we’ve seen in a long time and one of the best 3D printers overall.

Specifications: Elegoo Saturn 4 Ultra

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Build Volume 218.8 x 122.8 x 220 mm (8.5 x 4.8 x 8.6 inches)
LCD Screen 10.1″ Monochrome
Light Source COB Light Source + Fresnel Collimating Lens
X/Y Axis Resolution 19x 24 microns
Normal Exposure Time 2.5 seconds
Interface 4” Touch Panel
Connectivity USB, WiFi
Machine Footprint 327.4 x 329.2 x 548 mm (12.8 x 12.9 x 21.6 inches)
Machine Weight 14.5 kg (32 lbs)

Included in the Box: Elegoo Saturn 4 Ultra 

(Image credit: Tom’s Hardware)

The Elegoo Saturn 4 Ultra includes everything you need to get started as soon as you unbox the printer. You get a metal scraper for the build plate, a plastic scraper for the release film, paper funnels, disposable gloves, disposable masks, a set of Allen keys, a power cord with adapter and a printed manual. It also comes with a cheap plastic drip tray.

Also in the box is a USB thumb drive preloaded with Chitubox slicing software, a PDF of the manual and presliced test prints.

Printing Safety with Elegoo Saturn 4 Ultra

(Image credit: Tom’s Hardware)

The Elegoo Saturn 4 Ultra requires the same safety precautions as other resin printers. Uncured resin is dangerous, and the solvents used to clean your prints can be irritating to the skin. Use gloves and safety glasses when pouring resin and handling uncured prints.

Make sure the room you use your resin printer in is well-ventilated to avoid inhaling fumes. Spilled or dripped resin should be immediately cleaned with 99% isopropyl alcohol. After printing, make sure to wipe down your printer and bottles to remove smudges of uncured resin. Always keep your resin tightly sealed and safely stored out of reach of pets and children.

Assembling the Elegoo Saturn 4 Ultra

(Image credit: Tom’s Hardware)

The printer comes fully assembled. You only need to remove the packing materials, and you’re good to go.

Calibrating the Build Plate on the Elegoo Saturn 4 Ultra

Unlike other resin printers, the Saturn 4 Ultra doesn’t require manual calibration. It has a mechanical sensor that detects how well the plate and glass are fitting together and can adjust accordingly.

Design of the Elegoo Saturn 4 Ultra

(Image credit: Tom’s Hardware)

The Saturn 4 Ultra is a mid-sized resin printer with a very modern feel. It has an all-black shell with Elegoo’s stripe pattern on the hood, and futuristic angles built into the design. The screen is off centered, and set up portrait style. All the buttons and ports are on the right-hand size, which is nice as this printer is a good 30 pounds and not something you want to spin around to find the off switch.

The most noticeable difference is the hinged UV hood. Most printers are still using a lift-off box type hood, which is unhandy at best – and also requires having a good chunk of empty counter space nearby. This hood swings upward with one hand. It’s a huge improvement, but I’d still like to see a handle on the lid. I’m often opening or closing the lid after handling uncured resin, which can leave ugly smudges on your machine if you fail to clean them in time.

It’s a “smart” printer with several auto features to assist you. When you turn it on, it will run through a checklist to make sure all the components are working. It has sensors to make sure you have enough resin, and it can also tell if bits of a failed model are still stuck to the vat to prevent damage.

(Image credit: Tom’s Hardware)

The AI camera is a mixed bag – it can detect an empty plate, but only once the plate is above the vat, which is around 50mm. Likewise, it can’t create time lapses on anything shorter than 50mm. It has “warp detection” but it has to be very obvious – no alarm was sounded on the print below which started to peel off the bed.

(Image credit: Tom’s Hardware)

The camera is very handy for monitoring your prints, but it needs Chitu Manager switched on for it to work, which is not explained in the directions.

The printer also auto levels itself, so there’s no fumbling around with a piece of paper and a hex key. We’ve long had auto leveling on the FDM side of 3D printing, it’s wonderful to see this feature in resin.

The Saturn 4 Ultra has 12K resolution (11,520 x 5120) on a 10.1-inch monochrome LCD screen. This overwhelming number of pixels achieves a 19 micron accuracy on the X axis, which is incredibly crisp, especially when you consider that a human hair averages 70 microns. We’ve reached a point of resolution where layer lines simply disappear.

The build plate on the is laser-etched, which holds prints well while still being fairly easy to scrape off. The top of the plate isn’t quite sloped enough to get all the resin back into the vat, and the large block between the plate and the latch makes cleaning it unhandy. On the plus side, the machine comes with a drip tray you can wrap around the vat to contain resin droplets, and the vat has an excellent no-drip pour spout for getting resin back into the bottle.

(Image credit: Tom’s Hardware)

A scratch resistant screen protector is taped over the LED glass at the factory.

The touch screen is similar to other Elegoo resin printers and is well thought out and easy to use.

Slicers Compatible with the Elegoo Saturn 4 Ultra

(Image credit: Tom’s Hardware)

The Elegoo Saturn 4 Ultra ships with a free copy of ChituBox Basic, which does everything you need. It handles supports automatically, has tools for hollowing the model and adding a drainage hole so you can conserve resin.

The Saturn 4 Ultra is not yet supported by LycheeSlicer.

Washing and Curing Your Prints

(Image credit: Tom’s Hardware)

Before you can admire your prints, you’ll need to wash them with Isopropyl alcohol and cure with UV light. I like to give prints a 30-second hand rinse in a container of 95% Isopropyl alcohol, then a 2-minute rinse in the Elegoo Wash and Cure station, which is sold separately, and is currently on sale for $159 on Amazon

Completely dry the print with a hair dryer on cool – IPA left on the print will turn white. You can also let the print air dry in a place away from sunlight.

Supports are easier to remove before curing because they are softer. Clip the supports off with side cutters and use tweezers to remove stubborn supports. Remember to always wear gloves while handling uncured prints.

Then place the print in a UV curing station for a few minutes, or outside in bright sunlight for a few hours.

Your IPA should never be flushed down the drain, especially after being contaminated with uncured resin. Instead, keep using the resin until it’s too dirty, then leave the container open to evaporate. The remaining sludge can be cured with UV light or the sun before being thrown away.

Supports should also be cured before being thrown away.

Sample Prints on the Elegoo Saturn 4 Ultra

Wekster’s Rocket bust (Image credit: Tom’s Hardware)

I’ve been using the same model – Wekster’s Rocket – when I test resin printers, so I have something consistent to compare. This was printed in Elegoo 8K Standard resin using the default Chitubox settings, a .05 mm layer height, and a 3.5 second layer exposure time. This print took 3 hours and 13 minutes, which is pretty average. The results are excellent, with clean and clear details around the teeth on Rocket and the vines on Baby Groot. 

For comparison, this same model was printed in one hour and 31 minutes on the Anycubic M5s, a true high speed printer, using similar resin.

Vork and Codex by FeliciaDay3D (Image credit: Tom’s Hardware)

I loaded the Saturn 4 Ultra with Phrozen’s Aqua Grey 8K to see how it would do with a different brand of resin, and I was happy to see the Saturn had no trouble at all. This D&D miniatures printed very clean with beautiful details. These printed in 2 hours and 12 minutes using a 3.5 exposure time and a .05 mm layer height.

Cinderwing3D Rose Dragon (Image credit: Tom’s Hardware)

I’ll admit that I’ve been printing a lot of dragons lately, so I was curious how a Cinderwing dragon would do in resin with the Saturn 4 Ultra. I picked the Rose dragon, which has extremely delicate flower petals all around the body – which the Saturn printed without any issue. I didn’t bother hollowing it, and I also printed it flat on the plate without supports. It came off the bed with just a little bit of chisel persuasion. This is printed with Inland’s budget priced Standard bright red resin. I didn’t have to make any adjustments to the print settings, and it printed with a .05 layer height, using a 3.5 exposure time in one hour and 21 minutes. 

For comparison, a Bambu Lab P1P on its finest setting and using 99 walls to achieve a similar thickness, would take 12 hours and 42 minutes to print this same model. 

Bottom Line

The Elegoo Saturn 4 Ultra is an astounding machine with a remarkable level of detail and generous build volume. At 19 microns of resolution, we’ve hit a wall on the amount of detail we can appreciate with the naked eye. Elegoo finally made a choice to improve the printer itself and not just the light source, giving us a built-in camera, convenient hinged hood and a tilting vat that increases print speed without the need to get extra fine (and expensive) resin. 

Priced at $399, the Elegoo Saturn 4 Ultra is a reasonable price for a feature rich machine that has ample build volume and loads of resolution. By pairing up with an established slicer software, the Saturn 4 Ultra is incredibly simple to use for anyone starting out with a resin machine.

If you’re not ready for a next level machine and want to try something more basic, check out our Best for Beginners Anycubic Photon Mono 2 for $259. If you want a smaller printer for crafting miniatures, check out the Mars 3 Pro which is practically a steal at $184. 

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