Elegoo Neptune X

The Elegoo Neptune X is a 2021 FDM machine and the only cube-frame model in the Neptune line. The bed never moves in X or Y, it only drops down layer by layer while a gantry carries the hotend overhead — the same idea as the Creality Ender 5, but cheaper. Build volume is 220×220×300 mm, the extruder is an MK8 running bowden, and leveling is manual.

Elegoo rates it at 30–180 mm/s, 60 mm/s recommended. The hotend reaches 260 °C and the 250 W bed hits 100 °C in about five minutes, enough for PETG and ABS. Inside are POM V-slot wheels, silent drivers, an STM32F407 board and a 3.5-inch color touchscreen. Files arrive by USB stick or USB cable only — no Wi-Fi, no camera. The bed is a removable flexible magnetic sheet, it weighs 10.5 kg, and it ships as a partially assembled kit.

Pros

• Stationary bed: the part isn't accelerated along with the platform. Andrew Sink (3DWithUs) notes this is why tall TPU parts print fine here while a bedslinger topples them
• 250 W bed: it hit 100 °C in five minutes in the 3DWithUs test — PETG and ABS need no warm-up tricks
• Quiet: an owner review on 3DJake says it barely vibrates and prints unattended all night
• Rigid CNC-machined aluminum frame with braces under the bed — Amazon buyers say it doesn't feel cheaply built
• Out-of-box quality: the bundled Buddha file and a Cali-Dragon came out nearly defect-free at 3DWithUs, and a sailboat bridging test printed at 0.3 mm layers
• The filament runout sensor works: the print pauses and picks up from the same spot after reloading

Cons

• Power loss recovery is on the spec sheet, but in the 3DWithUs test the printer stopped extruding after the cord was pulled — no attempt ever finished
• No auto leveling: four thumbscrews and a five-point routine with A4 paper, no live Z adjustment. The board has a BL-Touch header and Elegoo has firmware for it, but you buy and fit the probe
• Assembly is heavier than a typical i3 — about an hour and a half of careful motion-system alignment, and the reviewer calls the wiring harness sloppy
• From Amazon reviews: swapping filament without pulling the idler is nearly impossible, some units shipped with bubbles under the magnetic bed adhesive, and replacement flex sheets are hard to source

The Neptune X suits anyone printing tall or flexible things: TPU, vases, thin towers — the stuff a moving bed topples. It's an intermediate machine: you build the frame and dial the bed by hand, but after that it runs predictably on PLA, PETG and ABS.

It's discontinued and out of stock on Elegoo's own store, so today it's a secondhand find. Want the same build area without the manual fiddling — take the Neptune 4 with auto leveling and Klipper, or the Neptune 4 Plus and Neptune 4 Max for bigger parts.

Reviews

• 3DWithUs — Elegoo Neptune X Review and Testing
• 3D Printing Geek — Neptune X vs Creality Ender 5 Pro (video)
• 3DJake — Neptune X owner reviews, 3.8 out of 5
• Amazon — customer reviews, 4.2 out of 5 from 28 ratings