Elegoo Neptune 4 Max

Only the SV08 Max, at three times the price, prints a part wider than this, and at $389 the Neptune 4 Max costs less than most 256 mm cubes. Eighty-five litres is roughly five times a P1S and nearly twice the Prusa XL's, for a tenth of the XL's price. The caveats scale with the bed: a 420 mm platform moving in Y has enormous inertia, the 121-point mesh is doing serious work to keep a plate that size flat, and a print filling the volume runs for days on an open frame with no camera to watch it. Warping is the real enemy at this scale — a part 400 mm long shrinks measurably as it cools, which is why the 110 °C bed matters more here than anywhere else. For signage, cosplay shells and full-size props in PLA or PETG, it has no competition on price.

Approx. price: ~$389
Build volume: 84.7 L
Per litre: $5
True multi-material price: No changer offered

Real speed ceiling

Not published

Elegoo does not publish a volumetric flow rate for the Neptune 4 Max, so its 500 mm/s claim cannot be checked against what the hotend can actually melt. We do not estimate one.

LAN-only modeKlipper firmware

Best forFull-size props, signage and cosplay shells printed in one piece rather than glued together.

Specifications

Build volume: 420 × 420 × 480 mm
Volume: 84.7 L
Motion: bedslinger
Max speed: 500 mm/s
Acceleration: 8,000 mm/s²
Max flow: Not published
Hotend max temp: 300 °C
Bed max temp: 110 °C
Enclosure: Open frame
Extruder: direct drive
Auto level: probe
Hardened nozzle: No
Input shaping: Yes

Materials, control and build

Multi-material: None offered
Firmware: Klipper
LAN-only mode: Yes
Cloud: Optional
Camera: No
Assembly: Partly assembled
Weight: 21 kg
Footprint: 675 × 660 × 745 mm

Features

420 × 420 × 480 mm — 84.7 litres, second only to the SV08 Max
110 °C bed across the full platform
121-point automatic levelling
Klipper with input shaping
Dual Z lead screws with a reinforced gantry

What it does well

84.7 litres at $389 — the cheapest litre of build volume in this catalogue
110 °C across a 420 mm bed is what keeps big parts from lifting at the corners
Klipper, input shaping and a dense levelling mesh on a machine this cheap
Prints in one piece what almost every other printer here needs cut into sections and glued

Where it gives ground

A 420 mm bed moving in Y has huge inertia — real speeds are a fraction of the 500 mm/s claim
Open frame, so large parts in anything but PLA and PETG will warp
Multi-day prints with no camera and no enclosure to protect them
675 × 660 mm of desk and 21 kg, plus partial assembly
No published flow rate to size the throughput of very large prints

The points above are read off published specifications, not from owner reports.

What owners report

Drawn from owner discussions in 3D-printing communities, not from our own testing — this site has no test lab.

What owners like

Owners name it directly when asking which large-format printer offers the best value, and the answers largely agree
The build volume genuinely enables projects that otherwise need sectioning and gluing, and owners post substantial designed-from-scratch work made on it
Klipper underneath means the tuning levers that matter on a machine this size are all available
Cheap enough that the size-per-dollar argument overrides most of its faults

Common complaints

Ripple banding is the characteristic complaint, reported as worse on the X axis than the Y and appearing in a regular repeating pattern
Owners describe working through full bed levelling and tilt-screw calibration without resolving print problems, to the point of losing confidence in the process entirely
A bed this large slinging in Y is the hardest possible case for ringing, and the banding reports are consistent with that
No enclosure, so 85 litres of anything but PLA and PETG will warp
No camera on a machine whose prints routinely run for days

The Neptune 4 Max is bought for one number and owner discussions confirm it: nothing else prints a 420 mm part for this money, and when people ask which large-format printer is the best value, this is the answer that comes back. Owners post substantial original work made on it, including designed-from-scratch pieces that simply would not fit elsewhere.

The characteristic problem is ripple banding, described as a regular repeating pattern and specifically worse along the X axis than the Y. That is consistent with the physics of the machine — a very large, heavy bed reversing direction on every layer is the worst case for resonance — and it is the reason its practical speed is far below its rating on anything tall.

The more discouraging reports come from owners who have done everything correctly. Full bed levelling, tilt-screw calibration, methodical work through the documented procedures, and still not getting acceptable results is a pattern that appears more than once, in one case to the point of the owner questioning filament printing generally. Buy it for size, budget time for tuning, and keep expectations for surface finish modest.

Questions owners ask

+What causes the ripple banding?

Owners report it as a regular repeating pattern, worse on X than Y. On a bed this size the most likely contributors are frame resonance from the large moving mass and belt tension. Lowering acceleration and speed helps more here than on smaller machines, because the inertia being managed is genuinely larger.

+Is it the best value large-format printer?

On volume per dollar, owners largely agree that it is — nothing else prints a 420 mm part at this price. The qualifications are that it is an open frame, so the materials list is short, and that surface finish on tall parts takes tuning that smaller machines do not need.

+Can it print ABS or ASA at size?

No. There is no enclosure, and a large part in ABS or ASA will contract unevenly as it cools and lift off the plate or split along a layer line. The larger the part, the worse it gets — which is unfortunate given that size is the entire reason to buy this machine.

+I've calibrated everything and prints still fail. What now?

Owners have reached exactly that point after full bed levelling and tilt-screw calibration. The things worth revisiting are frame squareness, belt tension, and whether the printer is on a surface rigid enough for a bed this heavy — a flexing table will reproduce banding no amount of calibration fixes.