Frequently asked questions

Load the STL into the tool at the top of this page, pick your printer (or set the maximum size each piece may have — usually the build volume minus a few millimetres of margin), and download the ZIP. You get one STL per piece, with connectors already in place, ready to slice.

An STL splitter cuts a 3D model file (STL, 3MF or OBJ) into smaller pieces that each fit on a printer's build plate, usually adding connectors — pegs, dovetails, magnets — so the pieces go back together after printing. Typical uses: printing a model that is too big for the printer, splitting a multicolor 3MF with its colors intact, printing pieces in parallel on several printers, and breaking a model up for shipping.

Drop the file into splicestl, set the piece size, and pick a connector in the joinery panel: square pegs (press-fit, default), dovetails (slide-together, single-axis splits), tenon/mortise, finger joints, magnet pockets or dowel holes. Connectors are placed on every cut face automatically, with adjustable size, count and tolerance. Download the ZIP and print.

For one straight cut, the Cut tool already in Bambu Studio, OrcaSlicer or PrusaSlicer is free and needs no extra software; all three add Plug/Dowel/Snap connectors or a dovetail. For a model that needs cuts on more than one axis, automatic fitting to your build volume, finger/magnet/tenon joinery, interlocking cut surfaces or a print-farm split, splicestl is free and runs in the browser. Paid desktop splitters are Split3r (€60–95 one-time) and LuBan3D ($30/month to $750 permanent); see the hands-on comparison.

Yes. splicestl runs entirely in your browser: no signup, no upload, no account, no watermark, no server-side processing. Your file never leaves your computer.

In current Cura that command comes from the Mesh Tools plugin, and it only separates meshes that are already disconnected shells inside one file — it does not cut geometry. Cura has no cutting-plane tool. splicestl cuts a continuous model along axis-aligned planes and adds joinery between the pieces; load the pieces into Cura afterwards to slice. Details in the Cura guide.

Those Cut tools cut one plane per operation and offer Plug, Dowel and Snap alignment connectors plus a dovetail cut mode. They do not plan a multi-axis grid, fit pieces to a build volume automatically, offer finger, magnet, tenon or peg joinery, or produce wave/zigzag/brick/pyramid surfaces. splicestl does those; the slicers remain the quickest option for a single straight cut. See the Bambu Studio and OrcaSlicer guides.

Autodesk stopped developing Meshmixer in September 2021 and no longer supports it; the last release was in 2018. splicestl covers the "plane cut + connectors" workflow it was most used for, in a browser with no installation. Blender, MeshLab and your slicer cover its sculpting, repair and support-generation workflows — the Meshmixer alternatives guide maps each one.

Default press-fit square pegs work for almost everything. Use dovetails for thin-walled pieces, where pegs would split the wall (single-axis splits only). Use finger joints on long flat cuts where you want maximum glue surface. Use magnet pockets for an assembly you want to take apart. Use dowel holes when you want to align pieces with a separate rod that is stronger than printed plastic.

Flat for most cases. Wave or zigzag when you want the seam to look less machine-cut. Brick or pyramid when you want the cut itself to lock the pieces without pegs — pyramid locks in both directions, brick in one. Sawtooth when you want a one-way ratchet that resists motion in a single direction.

Switch to "N pieces per axis" mode and set the count to 2 on the axis you want to split. Alternatively, set that axis's maximum dimension to half the model's size and leave the other axes unconstrained. Either way you get two STLs with matching connectors.

Rule of thumb: PLA 0.15–0.2 mm clearance per fit gives a firm press-fit that still comes apart; PETG needs 0.3–0.4 mm and ABS 0.4–0.6 mm because they shrink more. splicestl's default of 0.2 mm is tuned for PLA on a 0.4 mm nozzle. Print one peg-and-socket test before committing to a 30-piece split — flow calibration and slicer settings shift the effective fit by around ±0.1 mm.

Four approaches, in rough order of strength: press-fit pegs (no glue, can be taken apart — splicestl's default), glue plus alignment dowels (strongest permanent bond — cyanoacrylate or epoxy on the mating faces), magnets (snap-together, removable — magnet-pocket mode), or screws into printed bosses. For shear resistance without any insert, use the brick or pyramid cut shape.

Most often, filament shrinkage exceeds the tolerance gap — try 0.3 mm for PLA or 0.4 mm for PETG. Next most common: over-extrusion makes everything about 0.1 mm oversize; calibrate flow. Third: stringing or elephant's foot at the cut face is blocking the seam; clean both faces with a deburring tool. The tolerance setting in the joinery panel regenerates the same split with a wider gap without starting over.

Yes. If the model has open edges, T-junctions, duplicate triangles or inverted winding, a banner offers one-click repair: vertex weld, degenerate-triangle removal, duplicate-face removal, small-hole close, winding fix. The mesh is re-verified manifold before splitting. If you dismiss the banner, repair still runs automatically before a split when it is needed.

Not the silicone itself. You print the rigid mold box, pour liquid silicone into it around your master, and peel the box off after cure — the silicone is the finished mold, ready to cast resin, plaster or wax. splicestl/mold generates the printable box, with presets for silicone, resin, plaster and wax.

Yes, with splicestl/mold. Load an STL, OBJ, 3MF, GLB or PLY master; it repairs the mesh and builds a silicone shell (a printed two-part mother mold that hugs the master, so the silicone mold takes a fraction of the silicone), a two-part block you cast straight into, or a one-part open mold with a flat back. It maps undercuts and can fill them in one click. Everything runs in the browser.

Yes. If the size limits require several cuts on any axis, the tool generates all of them in one pass — 4, 8, 27 or more pieces depending on the model and the limits. Print farm mode then assigns those pieces across your printers.

No. splicestl is a static HTML page. Splitting, joinery, repair, mold generation and manifold verification all run in your browser with JavaScript and WebAssembly. The only network traffic is loading the page and its libraries.

splicestl is a set of free 3D-printing tools that run in your browser, made by one person, Ned Walsch. The name is "splice" plus STL, the 3D-model file format. It is not a St. Louis business and has nothing to do with the Splice music platform.

Yes. Every tool is free, with no account, no paid tier and no watermark. The site shows no display ads (the banner ads were switched off on 6 November 2026). It earns a small commission when someone buys through its Amazon affiliate links, and the code is MIT-licensed.

Every tool has an automated test suite that runs in a headless browser before each release. The splitter's suite runs 23 scenarios (pegs, dovetails, tenons, finger joints, magnets, dowels, seven cut shapes, a repaired open mesh, a multi-part Bambu 3MF) and checks that every piece is a closed solid and that every connector was placed. Other suites decode each 3D QR code with a QR reader and check the calculators against worked examples. There is no independent audit or published review yet; the benchmark page shows timings on 200,000- and 1-million-triangle models.

Yes. Choose a printer preset (152 printers) or type the largest size a piece may be on X, Y and Z, and splicestl plans the cuts on all three axes and splits the model by itself — no planes to place. The cut handles stay draggable if you want to move a seam, and Pro settings add seam-aware placement, manual cuts and seven cut-surface shapes.

Yes. splicestl reads 3MF (and OBJ) as well as STL, including project files saved by Bambu Studio, OrcaSlicer and PrusaSlicer: painted regions and per-part filament assignments load with their colours, and the pieces can be written back as 3MF — one file per piece, one per build plate, or a single Bambu / Orca project with every plate laid out. See the 3MF splitter page.