Auto Split is Meshy's automatic model-splitting feature that splits a 3D model into separate, printable parts in about 40 seconds — each cut auto-capped watertight and auto-arranged on the build plate, printable and easy to fit back together. It's built to simplify one of the trickiest steps in 3D printing: turning a whole model into parts you can actually print and assemble.
Generating a model was never the hard part — turning it into printable parts was. A whole model rarely prints well in one piece: it may be too big for the plate, or need multiple colors, or come out cleaner when separated at the seams. Auto Split solves this by segmenting the model along its natural structure, sealing every cut into a solid part, and laying the parts out on the plate for you — no hopping between separate mesh-editing and slicing tools to cut, cap holes, and re-align by hand.
ℹ️ Availability: Auto Split currently works on untextured (draft) models. Textured models aren't supported for splitting yet.
What Is Auto Split?
Auto Split analyzes a model's geometry and detects the natural boundaries between its parts — limbs, props, accessories, and other functional components — then separates them into distinct pieces. When it finishes, the model is shown as color-coded blocks, where each color is a separate part.
Three things make the parts genuinely usable:
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Smart Cuts — cuts follow the model's natural structure, placed at flat, clean boundaries so parts can be bonded or pinned back together.
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Auto-capped watertight — every cut face is automatically sealed into a closed, solid part, so it slices without errors.
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Built to assemble — parts are auto-arranged on the build plate to fit your printer and designed to fit back together.
Because segmentation is automatic, you never select faces or draw split lines by hand. And unlike a simple planar cut — which can only slice through a single flat plane — Auto Split separates the model along its natural part edges, so cuts fall at sensible part boundaries rather than straight across a surface. Read the Auto Split launch post for more background.
Why Split a 3D Model into Parts? 3 Common Use Cases
Splitting is what turns a print-ready AI 3D model into something a real printer can actually handle. The three most common reasons to do it:
3D Printing Large or Oversized Models
Most home printers have a build volume of roughly 200–260 mm per side. A large figure, helmet, or vase is often bigger than that, so it simply won't print as a single piece. Auto Split breaks it into plate-sized parts you can print in batches and assemble afterward — the practical answer to how to split a 3D model for printing.
Multi-Color Printing Without Waste
On multi-color FDM, every filament change burns purge waste — often more material than the model itself. Splitting the model by color so each part prints in a single filament cuts both waste and time dramatically.
Fewer Supports, Cleaner Surfaces, Higher Success Rate
Overhangs and outstretched parts — an extended arm, a flowing cape — need a lot of support material when printed whole, and removing that support leaves scars that are hard to sand. Splitting those parts off so each can be printed flat or at a better angle means fewer supports, cleaner surfaces, and a higher print success rate.
How to Split a 3D Model into Parts with Meshy Auto Split? (7 Steps)
Here's the complete workflow — from a model to printed, assembled parts. The Meshy side takes just a few clicks: no manual mesh editing, no cutting or hole-capping in a separate 3D tool, no third-party splitting software.
Before you start: you need an untextured (draft) model. Textured models can't be split yet.
Step 1: Generate or open a 3D model
Create a 3D model with Meshy — from a text prompt (text-to-3D) or a reference image (image-to-3D) — or open one you've already made. Use the untextured "white model" (draft) version — that's the input Auto Split needs, so don't apply textures before splitting. You'll work with it in the Print workspace, where you can orbit, zoom, and inspect it before splitting. Starting from a photo? See How to Convert a Photo to a 3D Printable Model.
Step 2: Click Auto Split
There are two ways to reach Auto Split:
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In the Print workspace — click Auto Split in the top-left of the screen.
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While generating a model — tick the Auto Split option in the generation settings, so an untextured model comes out already split, with no need to open the Print workspace afterward.
Step 3: Wait for the split to complete (about 40s–1min)
Auto Split analyzes the geometry and separates the model into parts. This takes about 40 seconds to 1 minute. When it finishes, the model is displayed as color-coded blocks — each color is a separate part. Open the right-hand panel to see the parts list — each part, its color, and the total count.
You don't need to select faces, draw cut lines, or set seams — segmentation is fully automatic, and every cut is sealed watertight for you.
Step 4: Inspect the split with the slider and views
Take a moment to review the result before exporting:
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Drag the slider at the bottom to watch the parts separate and come back together, layer by layer — a quick way to see how the model comes apart.
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Switch views:
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Assemble — the assembled view, to check the parts fit back together.
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On Plate — Meshy automatically arranges the parts on the build plate, so what you download is already laid out for printing. Check that the part count looks right and nothing overhangs the plate.
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🔁 Not happy with the split? Click Re-split to run it again. ⚠️ Each split costs 10 credits (Re-split included) — it is not the same as a free model-generation Retry.
Step 5: Export your parts
When you're happy with the split, export the parts — the format depends on which view you're in:
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From the On Plate view (parts laid out for printing), download as 3MF, STL, OBJ, or GLB.
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From the Assemble view (the assembled model), download into any of Meshy's eight export formats.
Step 6: Send the parts to your slicer
Load the downloaded parts into your slicer. Auto Split is designed to hand off in one click to slicers like Bambu Studio and others. Because every cut is auto-capped watertight, each part is a solid, sliceable body — orient each one for minimal support and slice as usual. See How to 3D print with Meshy for a full walkthrough.
Step 7: Print and assemble
Print the parts and fit them back together along the natural seams. Because Auto Split cuts along the model's part edges and caps each cut, the pieces line up and assemble cleanly.
How to Get Clean and Accurate Auto Split Results?
Auto Split runs automatically, but a few habits get you cleaner parts and fewer re-splits:
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Start with an untextured (draft) model. It's the required input — textured models can't be split yet.
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Pick models that split well. You'll get the best results on:
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Humanoid figures and characters — clear limbs, without too many small surface accessories
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Props — already multi-part by nature, so the split logic is clean
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Small landmark pieces and cartoon / game-style models
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Figures on a detailed base or diorama
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Be cautious with tricky geometry — these are more likely to produce bad results:
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Models with windows or enclosed openings
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Densely intertwined detail — chains, hair, or mesh-like surfaces
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Highly abstract forms with no clear part boundaries
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Review before exporting. Use the slider and the Assemble view to confirm the parts fit back together, and check the parts list on the right.
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Switch to On Plate before downloading so the parts arrive already arranged for printing.
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Re-split if the result isn't right — note that each split (including Re-split) costs 10 credits, so it's worth reviewing before you re-run. A cleaner, less tangled model usually splits better.
FAQ
How do you split a 3D model into multiple parts?
Use Meshy Auto Split: open an untextured (draft) model in the Print workspace and click Auto Split. It separates the model into color-coded parts in about 40 seconds to 1 minute, seals each cut watertight, and arranges the parts on the build plate for you to download and print.
Can I split an STL file into parts online for free?
Auto Split runs online in the Meshy Print workspace — there's nothing to install. It splits untextured (draft) models generated in Meshy, not arbitrary uploaded files, so it isn't a general "upload-any-STL" splitter. It also isn't free: each split costs 10 credits, and every Re-split costs another 10.
What file formats does Auto Split support?
The input is an untextured (draft) model in Meshy (textured models aren't supported yet). The download formats depend on which view you export from:
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On Plate (parts laid out for printing) — 3MF, STL, OBJ, and GLB
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Assemble (the assembled model) — all eight of Meshy's export formats: FBX, OBJ, USDZ, GLB, STL, BLEND, 3MF, and DXF
STL, OBJ, and 3MF cover the common 3D-printing slicers like Bambu Studio.
How to create a multi-part 3MF file for multi-color printing?
3MF is a modern format that stores multiple parts — along with their color and part data — in a single file, which makes it ideal for multi-color 3D printing. To create one with Meshy, split your model with Auto Split, then download it as a 3MF from the On Plate view (which also supports STL, OBJ, and GLB). Because Auto Split separates the model into individual parts, the resulting 3MF keeps every part together in one file, ready to assign colors in your slicer.
How long does Auto Split take?
Auto Split usually produces a full split preview in about 40 seconds to 1 minute, depending on model complexity. If you're not happy with the result, you can Re-split (this consumes credits).
Splitting vs. Cutting a 3D Model — What's the Difference?
A manual planar cut can only slice straight through the model along a single plane. Meshy's Auto Split instead cuts along the model's natural part edges, following the color and part boundaries — so the pieces reassemble more neatly with fewer visible seams.
