Elegoo Neptune 4 Plus build volume: 320 × 320 × 385 mm — what fits, and how to print what doesn't
Quick answer: the Elegoo Neptune 4 Plus prints objects up to 320 × 320 × 385 mm (X × Y × Z, that is width × depth × height) — 39.4 litres, which ranks #27 of 152 printers in the dataset. The largest cube is 320 mm; a thin flat part can reach about 443 mm along the bed diagonal. Anything bigger is split into pieces with connectors — the splitter has a Elegoo Neptune 4 Plus preset.
What the numbers mean for your model
Build volume is quoted as the box the nozzle can reach, X × Y × Z. A model fits whole when it fits that box in some orientation, which is more forgiving than it sounds: a long flat part can lie diagonally across the 320 × 320 mm bed (diagonal 453 mm, so about 443 mm usable once a margin is left for the brim), and a tall part can stand up to 385 mm if its footprint fits. The splitter checks every orientation before it decides a model needs cutting, and reports "already fits" when it does.
When it does not fit, the number of pieces depends on which axis overflows. If only the longest dimension is too big, this is what a Elegoo Neptune 4 Plus needs, allowing a 2 mm margin per piece:
| Model's longest side | On the Elegoo Neptune 4 Plus | Piece length |
|---|---|---|
| 250 mm | fits whole | — |
| 300 mm | fits whole | — |
| 400 mm | 2 pieces | 200 mm each |
| 500 mm | 2 pieces | 250 mm each |
| 600 mm | 2 pieces | 300 mm each |
| 800 mm | 3 pieces | 267 mm each |
Pieces along the printer's longest axis (385 mm). A model that overflows two axes needs the product of the two counts — the splitter plans that automatically, and usually finds a layout with fewer pieces than the naive grid by rotating the model first.
Elegoo Neptune 4 Plus notes
The Neptune 4 Plus is the 320 × 320 × 385 mm member of the family — 39 litres, enough for most helmets whole. Its 385 mm Z is taller than most printers in its price class, which makes it a good target when a split model has one long piece to stand up.
Printers with a similar build volume
| Printer | X × Y × Z (mm) | Litres | Rank |
|---|---|---|---|
| Anycubic Kobra 2 Plus | 320 × 320 × 400 | 41.0 | #25 |
| Elegoo Neptune 3 Plus | 320 × 320 × 400 | 41.0 | #26 |
| Snapmaker 2.0 A350 | 320 × 350 × 330 | 37.0 | #28 |
| FLSun V400 | 300 × 300 × 410 | 36.9 | #29 |
| Sovol SV08 | 350 × 350 × 345 | 42.3 | #24 |
| Bambu Lab H2D | 350 × 320 × 325 | 36.4 | #30 |
Other Elegoo printers in the dataset: Elegoo Centauri Carbon, Elegoo Neptune 2, Elegoo Neptune 3, Elegoo Neptune 3 Max, Elegoo Neptune 3 Plus, Elegoo Neptune 3 Pro, Elegoo Neptune 4, Elegoo Neptune 4 Max, Elegoo Neptune 4 Pro.
Split a model for the Elegoo Neptune 4 Plus
- Open splicestl with the Elegoo Neptune 4 Plus preset selected and drop the STL, 3MF or OBJ on the page. Nothing is uploaded.
- The split runs by itself to 320 × 320 × 385 mm minus a margin, on all three axes at once. Drag a cut handle to move a seam; Shift-click the model to mark a spot a seam must avoid.
- Pick connectors — pegs by default; dovetails, finger joints, magnet pockets, dowel holes, screw joints or your own — and download the zip: one file per piece lying flat, the connectors, a README and an assembly sheet.
Frequently asked questions
What is the build volume of the Elegoo Neptune 4 Plus?
320 × 320 × 385 mm (width × depth × height), which is 39.4 litres. That is the manufacturer's stated printable volume as used by splicestl's Elegoo Neptune 4 Plus preset; the physical bed may be a few millimetres larger.
What is the largest object you can print on the Elegoo Neptune 4 Plus?
A 320 mm cube fits outright. A flat part can be longer by lying on the bed diagonal: up to about 443 mm long if it is narrow and under 385 mm tall. A tall part can stand 385 mm high if its footprint is within 320 × 320 mm. Anything that exceeds these in any orientation has to be split.
How do I print something bigger than the Elegoo Neptune 4 Plus's build volume?
Split it into pieces that each fit, add connectors at the cuts, print the pieces and join them. The free browser splitter at splicestl.com has a Elegoo Neptune 4 Plus preset: load the STL, 3MF or OBJ, choose the preset, and the model is cut on all three axes to fit 320 × 320 × 385 mm with pegs, dovetails or magnet pockets placed at every cut. Download gives one file per piece plus an assembly sheet.
Related
Source and changes. Dimensions are the manufacturer's published specification as recorded in the splicestl build-volume dataset (CC BY 4.0; the tool's preset table, read 13 October 2026). Derived figures (litres, diagonal, rank, piece counts) are computed from those three numbers by tools/build-printer-pages.py. Page published 31 October 2026. If the manufacturer has changed the specification, tell us and the dataset, the preset and this page change together.