Cut oversized models and rejoin them with connectors A Blender add-on that splits big STL models into printable parts along their natural joints, with pegs, dovetails or magnet pockets that fit, and tells you which pieces fit your printer. Finds the parts. Slide to choose how many. The split follows the shape: neck, shoulders, joints. Cuts you can edit. Every seam is a curve you drag until you commit. Nothing is cut before that. Joints that mate. Rectangle, round, D or dovetail pegs, or magnet pockets, sized in real millimetres. New in 1.3 Seam From Loop. Hover a ring round an arm or a leg and click to lay a seam; G follows the groove. Peg profiles. Rectangle, round, D that fits only one way, or dovetail. Your printer and Print View. Pick your printer, see which pieces fit, each on its own plate. One 3MF. Every piece in one file, laid flat on its cut or in its print pose. See it in action Before / after: one model in, a printable kit out Miniatures, mechs, creatures, vehicles, busts, props and AI-generated meshes. Wargaming miniature · Mech · Sculpted character · Vehicle Why not just bisect it by hand? You can. Bisect gives you a flat cut and two loose halves. Then you align the pins by eye, boolean them in one at a time, and find out the fit was wrong after a six hour print. Cleave keeps the cut editable until you commit, fits the joints for you, and lets you check they seat before anything reaches your slicer. Shape-aware parts. It finds where the model wants to come apart, instead of you placing planes. Curved, editable seams. A cut can follow a collar or a sleeve, not just a flat plane. A fit check. Reassemble puts the pieces back from their cut faces, so you see the joints seat before printing. The workflow: one sidebar tab, six steps 1. Analyse: pick how many parts, watch it split Press Scan Model, then drag the Parts slider. Cleave paints the model into coloured parts that follow its shape: a figurine breaks at the neck and shoulders, not across the face. Nothing is cut yet. 2. Refine: fix any part by hand Merge parts, repaint a boundary with the brush, lasso or box, split one part again, or plant a part the analysis missed. Subsplit A Part re-analyses one part and leaves the rest alone, and Snap To Creases pulls each boundary onto the real creases. Restore Original takes you back to the uncut model at any time. Brush · Lasso · Box Add A Part · Merge · Subsplit A Part 3. Seam: turn a boundary into an editable cut Propose All Seam From Part draws the cut path as a curve. Drag its points, add or drop one, and preview the cut surface before anything is cut. Flatness and Tilt U/V pull a seam onto a flat mating plane, which prints and glues better. Or use Draw Seam Line: draw across an arm, get a seam. New in 1.3: Seam From Loop. Hover a ring round an arm or a leg and click: Shift+Wheel turns it, Ctrl+Shift+Wheel leans it, G makes it follow the groove under the cursor so the seam hides in the relief, and S snaps it onto a nearby groove. Auto propose seams Seam From Loop Follow the groove (G) Edit the curve · Preview the cut · Draw Seam Line 4. Cut: commit, and the joints are already there Press Cut Seam. Parts were only a proposal: now they become real, separate pieces, and default connectors appear on every cut. 5. Connect: set every joint in real millimetres Pick a connector per joint: a peg, in four profiles (rectangle, round, D or dovetail), or magnet pockets, then its size and clearance. Every joint is listed, one row per mated pair. Select one and it grows handles on a cut's joints: slide it, turn it, resize it. No need to Apply: preview connectors are baked into the pieces on export either way. Fill Cut With Connectors covers a whole cut in one click, Flip swaps which half carries the peg, and Presets save your settings for the next model. Auto Scale is off by default; either way the panel warns when a connector does not fit. 6. Check and export: prove the fit, then export for your slicer Exploded View pulls the pieces apart, Reassemble puts them back from the cut faces. Then export one STL per piece or one 3MF, in millimetres, named by a template, each piece laid flat on its cut, or in its print pose once you choose a printer. Undo Last steps back one cut, and everything is saved in the .blend. Connectors: pegs, magnets, or a plain seam Real Cleave cuts on one cube: the peg in its four profiles, magnet pockets, or a plain seam. Peg, rectangle A tapered pin on one piece, the matching socket on the other, pushed straight home. Peg, round A cylinder or a cone, in a matching round socket. Peg, D Round with one flat side, so it fits only one way. Peg, dovetail Tapered on two sides, straight on the other two. A push fit too. Magnet pockets A matching pocket in each face for disc magnets from 5×2 to 10×3 mm, or your own size. None A plain flat seam, for parts you glue or that sit on their own. Your printer: know which pieces fit before you slice New in 1.3: pick your printer once, and every piece tells you whether it fits its plate. Your printer. Over 120 models built in, or your own build volume, chosen in the preferences. Fits or not. Each piece shows whether it fits. Export names any piece too big for the printer. Print View. Each piece on a plate of its own, in its print pose. Nothing in the scene moves. Print View Performance: it does not choke on a real sculpt Measured on a 414,000 face model: about 6.5 s to analyse, 2 s to propose a seam, 3.3 s to cut. Tested up to 2 million faces. The panel quotes the expected time on your own machine, and Esc stops a long scan, propose, cut or split. AI-generated models: made for Meshy, Tripo and the like Generators fuse arms, armour and props into one shell. That is exactly what the automatic analysis is for: it finds where an arm meets a torso even inside one merged mesh. Checked up front. The panel tells you whether the mesh is solid before you start. Repaired in one click. Make Manifold welds open seams and fills holes before you cut. Split by shape. The parts follow the model, not the way the generator merged it. Print ready: every piece, laid out like a kit Made for: miniatures and wargaming, busts and statues, mechs and vehicles, cosplay props, terrain, AI-generated models (Meshy, Tripo), resin and FDM. Compatibility Blender 4.2 LTS and newer, as an extension Windows, macOS and Linux Pure Python with the numpy Blender ships, no internet needed What you get The add-on as a .zip archive Full Python source, GPL-3.0 or later Free updates for the 1.x line Best-effort support through the store Good to know Cleave stops at the file, STL or 3MF, laid flat where it can be. Slicing, hollowing and supports stay in your slicer. If it will not cut your model, message me through the store before you give up on it. Everything it does Automatic parts detection Shape-aware parts. Redrawn live as you slide. Snap To Creases. Pulls each boundary onto the real creases. Merge, brush, lasso, box. Repaint any boundary by hand. Through and Fill Gaps. Paint the faces hidden behind the model without X-ray, and the ones a stroke missed. Add A Part. Plant a part the analysis missed. Subsplit A Part. Re-analyse the torso, leave the rest alone. Seams Editable curves. Drag, add and drop points in the viewport. Flatness and Tilt U/V. Pull the seam onto a flat mating plane. Prints and glues better. Detail. Keep the boundary's natural wander, or smooth it. Draw Seam Line. Draw across an arm, get a seam. Seam From Loop. Hover a ring round an arm, click, get a seam. Shift+Wheel turns it, Ctrl+Shift+Wheel leans it. Follow groove. G makes the ring follow the fold under the cursor, so the seam hides in the relief. Snap to groove (S) pulls it onto a nearby groove. Connectors Peg and socket. True millimetres. A push fit, straight home. Peg profiles. Rectangle, round (cylinder or cone), D that fits only one way, or dovetail, tapered on two sides and straight on two. Magnet pockets. 5×2 to 10×3 mm, or your own. Fill Cut With Connectors. A whole cut in one click. Auto Scale. Off by default. Turn it on to keep each one inside both pieces; either way the panel warns when one does not fit. Viewport handles. Slide, turn, scale, or size one axis, on a cut's joints. Flip. Swap which half carries the peg. Presets. Save your own, apply them anywhere. Printer Your printer. Over 120 models built in, or your own build volume. Each piece shows whether it fits. Print View. Each piece on a plate of its own, in its print pose. Nothing in the scene moves. Check and export Explode and Reassemble. The check that proves the joints seat. One STL per piece, or one 3MF. Millimetres, with a filename template. Lay flat on the cut. Each piece written resting on its cut, or in the pose Print View shows. Export names any piece too big for the printer. Make Manifold. Welds open seams and fills holes before you cut. Hollow models stay hollow. Undo Last, Restore Original. Esc stops a long scan, propose, cut or split. Saved in the .blend. Reopen tomorrow and carry on, uncut seams included. Rename, duplicate, separate or join pieces and their connectors follow. FAQ Which Blender versions does it work with? Blender 4.2 LTS and newer, as an extension. Install by dragging the zip into Blender, or Preferences, Add-ons, Install from Disk. Developed and tested on 4.2 LTS and 5.2 LTS. Does it work on AI-generated models? Yes. The panel tells you up front whether the mesh is solid, and Make Manifold welds open seams and fills holes before you cut. Fused parts are what the automatic analysis is for: it finds where an arm meets a torso even when the generator merged them into one shell. Does it work on macOS and Linux? Yes. It is pure Python and uses only the numpy that ships inside Blender. Nothing to compile, nothing to install, no internet connection needed. Does it slice, hollow, or generate supports? No. Cleave stops at the file, one STL per piece or one 3MF, with each piece laid flat on a cut face where it can be. Hollowing, supports and slicing stay in your slicer, where they belong. What connector types are there? Three: peg and socket, magnet pockets, and None for a plain seam. The peg comes in four profiles: rectangle, round (a cylinder or a cone), D, which fits only one way, and dovetail. Can I undo a cut? Yes. Undo Last steps back one, Restore Original goes back to the uncut model. Applying a connector edits both facing pieces, so that is one row, one undo, and both pieces come back with the connector live again. Can I sell what I print with it? Yes. Cleave's licence covers the add-on, not your models or your prints. What you may do with a model depends on that model's own licence, not on this one. Refunds? All sales are final, no refunds. If Cleave will not cut your model, message me through the store first and I will help you sort it out. Support & Updates Support is best-effort, I answer as I can. Free updates for the 1.x line. Report a bug or ask for a feature with a message through the store. (Include your Blender version, your OS, and what the panel header said for bugs.) More models Setup Download the Cleave .zip. Drag it into Blender, or Preferences, Add-ons, Install from Disk. Open the Cleave tab in the 3D Viewport sidebar (N). New to Cleave? Watch the walkthrough first. Every tool, step by step, on a real figure: watch on YouTube.