Split a large model to fit your printer bed
When a model does not fit on the printer bed, you split it into parts sized to the build volume and print it in pieces, then assemble. BunnySplit does this automatically: it cuts the model to your bed size and places snap-fit joints on the cut faces so the pieces come together without glue. Upload a large model — get a set of printable parts with connectors.
How it works
The engine looks at the model's bounding size and your bed, finds where to cut so each piece fits, and splits the geometry. Along each cut it builds tenon-and-mortise joints, so after printing the pieces align by their own keys and snap together.
- Upload a model that does not fit on the bed.
- Set your printer's bed size (or take a safe common size of ~250 mm).
- The engine breaks the model into printable pieces and adds joints on the cuts.
- Download the 3MF, print the pieces in turn, then assemble.
Which bed size to target
The build volume of consumer FDM printers varies, so split for your own bed:
- Bambu Lab X1C / P1S / P1P / A1 — 256 × 256 × 256 mm.
- Creality Ender-3 (V2/V3/S1) — 220 × 220 × 250 mm.
- Prusa i3 MK4 / MK3S+ — 250 × 210 × 220 mm.
- Prusa XL — 360 × 360 × 360 mm (for genuinely large parts).
If you would rather not tie it to one model, take ~250 mm per side as a safe ceiling for a single part — a piece that size fits both the Ender-3 and the Bambu Lab.
So the pieces come back together
Splitting is only half the job — the pieces must meet. BunnySplit engine defaults for assembly:
- Joints on the cuts: tenon-and-mortise with a 0.30 mm per-side fit by default plus material shrinkage compensation (PLA 0.3%, PETG 0.5%, ABS 0.7%), so the male half enters the female after cooling.
- Seam orientation: the cut and joint are rotated so the working load runs along the layers; across layers an FDM part is weaker (Z strength is roughly 40–80% of in-plane strength), and a seam along the layer bond would fail first.
Hands-on tips for printing big models in pieces are in printing a large model on a small printer; how the joints on the cuts are built is in snap-fit joint types.