Elegoo Neptune 3 Max

The Elegoo Neptune 3 Max is the biggest machine in the Neptune 3 family and one of the few affordable ways to print a half-metre part in one piece: a 420×420×500 mm build, direct drive, open frame. It's discontinued and listed out of stock in Elegoo's store. All3DP named it a budget pick among large printers in 2023.

The plate is 430×430 mm, rated speed 30–180 mm/s with 60 mm/s recommended, layers 0.1–0.4 mm. The 0.4 mm brass nozzle reaches 260 °C and the PEI sheet 100 °C, drawing 420 W of the 480 W supply. A direct extruder with a 3:1 reduction and SUS303 gears runs PLA, PETG, ABS, ASA and TPU. Z uses two lead screws, two motors and two tie rods, with 63-point leveling. The printer occupies 658×632×740 mm, and the moving bed needs nearly a metre of depth.

Pros

• 88 litres of build volume for $350: helmets, enclosures and life-size parts come out whole, with no gluing
• The bed heats evenly: a 25-point survey showed only 0.5 °C of spread, which maps straight onto warping on big parts
• Direct drive with a 3:1 reduction pulls TPU confidently and feeds reliably through long prints
• Quiet for its size: measured under 40 dB on average against a rated ≤50 dB
• Assembly takes 15–20 minutes, and 63-point leveling gets the first layer down without paper shims
• LED lighting, a removable 4.3-inch screen and a pull-out tool drawer in the base — a Max-only touch

Cons

• The print head is the same one used on the 3 Pro and 3 Plus: it lacks flow for a 420×420 mm bed, so owners fit a 0.6 mm nozzle right away
• 260 °C is a hard firmware ceiling: one owner swapped the hotend, thermistor and heatbreak and still couldn't go higher, so ABS and ASA mean moving to Klipper
• Tall models wobble: a half-metre print can fail in the final centimetres
• A base warped by shipping is an acknowledged defect, and Elegoo itself says the 3 Plus and 3 Max need re-leveling before nearly every print
• It needs about 980 mm of front-to-back clearance, and since firmware 1.2.5.1b the Z-offset drifts 0.3 mm with room temperature

The Neptune 3 Max suits people who need the size above all: cosplay props, life-size figures, enclosures, large jigs. Speed and precision are middling, but a half-metre part prints in one run. It's a poor first printer: manual tramming and the 260 °C ceiling assume you'll get into the hardware.

Bottom line: the cheapest ticket into large-format printing circa 2023, where the volume is paid for with a stock hotend and manual calibration. It isn't sold new — the direct replacement today is the Elegoo Neptune 4 Max with a 420×420×480 mm volume, Klipper and a claimed 500 mm/s.

Reviews

• Tom's Hardware — Elegoo Neptune 3 Max Review
• 3DPrinterBee — Elegoo Neptune 3 Max Review (bed temperature and noise measurements)
• DIY Machines — Elegoo Neptune 3 Max Review