Elegoo Neptune 4 Max

The Elegoo Neptune 4 Max is the biggest machine in the family: an open-frame bed slinger with a 420×420×480 mm build volume and Klipper preinstalled. You buy it to print a helmet, a housing or a life-size prop in one piece. Tom's Hardware scored it 3 out of 5: the size and speed come bundled with buggy firmware.

Build volume is 420×420×480 mm on a 430×430 mm PEI plate; the machine weighs 18.1 kg at 658×632×740 mm. The nozzle reaches 300 °C, but the bed stops at 85 °C — the smaller Neptune 4 Plus does 100 °C. Rated speed is 500 mm/s at 8,000 mm/s², while reviews settle at 200–300 mm/s. Accelerometers sit on the X and Y axes.

Pros

• The volume swallows helmets, housings and signage whole, and the printer still fits through a doorway
• Klipper tunes Input Shaper off those accelerometers and clears ringing off the walls, no extra hardware needed
• Tom's Hardware measures it twice as fast as its predecessor, the Neptune 3 Max
• Wi-Fi, LAN and USB: 3DWithUs keeps printer and PC in different rooms and sends jobs over the network
• 121-point auto leveling held for months of use at iXBT after a single run
• 5.2:1 direct drive, titanium heatbreak, 60 W ceramic heater: PETG runs steady even on big vases

Cons

• The bed caps at 85 °C and takes 13 minutes to get there (iXBT). ABS barely sticks that low: 3DWithUs had a bracket tear off mid-print
• Flatness over 420×420 mm is the weak spot: 0.2 mm of corner deviation at iXBT, 0.3 mm for a 3DToday owner, and bed play means pulling the platform
• Firmware is rough: Tom's Hardware set Z through Klipper's web interface because screen leveling wouldn't hold, and homing long slammed into the stops
• 18.1 kg plus a moving bed that size shakes furniture — 3DWithUs put the printer on the floor to save print quality

It makes sense for people who keep hitting the size ceiling: cosplay and props, enclosures, models, signage, big functional parts. PLA and PETG are the working materials; ABS and ASA are listed, but an 85 °C bed and an open frame warp large parts. Tom's Hardware won't recommend it to beginners.

Bottom line: the cheapest route to a 420×420 mm plate with Klipper and Wi-Fi, if you can live with the 85 °C ceiling, a long setup and firmware with a temper.

Reviews

• Tom's Hardware — Elegoo Neptune 4 Max Review: Bigger, Buggy and a Bit Faster (3/5)
• 3DSourced — Elegoo Neptune 4 Max: Hands-On Review
• 3DWithUs — Elegoo Neptune 4 Max Review: Testing, Settings, Tips