After installation, you will need to activate the software.

Launch Split3r, the activation window will open automatically.

If you need to return to this page later, you can access it from the menu: Help > Registration.

Enter the email address and name exactly as provided in the activation email you received, then click “Validate”.
These credentials are strictly confidential and must not be shared with third parties.

Activation – Troubleshooting

If the activation process does not complete successfully, please check the following points:

Make sure your computer is connected to the Internet.
Verify that the system date and time of your computer are correct. An incorrect date can prevent license validation.
Ensure that your firewall or security software is not blocking Split3r or its network access.

After correcting any of these points, restart Split3r and try the activation again.

Split3r is organized around four main working modes that structure your workflow from start to finish.
Use them in sequence : PREPARE → PRE-SPLIT→ SPLIT→ EXPLODE, to move from model preparation to plane setup and final result review.

PREPARE

: Import and prepare your model (repair, scale, shell) inside a tracked Workzone. The Active file here is the one used for the next steps.

PRE-SPLIT

: Position and adjust the cutting planes; use hotkeys and X/Y/Z controls to fine-tune the split configuration.

SPLIT

: is the operation that runs after PRE-SPLIT and before you review results in EXPLODE. It takes the Active file and your current plane configuration, computes the partitions, and writes the output to a new results folde

EXPLODE

: Inspect, filter, and organize the resulting parts, manage visibility and bulk actions from the parts tree.

If you discover an issue, e.g., mispositioned cutting planes or very small parts that could have been avoided, switch back to PRE-SPLIT, adjust the planes’ positions and sizes, then run SPLIT again.

Switch between PREPARE, PRE-SPLIT, SPLIT and EXPLODE modes from the top bar. The 3D viewport shows the active model, the left panel changes per mode

PREPARE MODE

WORKZONE TREE : HOW IT WORKS

Top folders = Split results.
The folders shown above the files (e.g., results_<active-file>.stl) contain the parts generated by Split. You can keep multiple results to compare iterations.

.s3r project file = Workzone settings.
The .s3r file stores Workzone parameters: selected printer, plane positions, UI options, and other session data for this project.

VISIBILITY LOGIC.

Checked = the part/file is visible in the 3D view.
Unchecked but selected (clicked in the tree) = the part/file is shown transparent, for quick inspection without full visibility.

ACTIVATE / DELETE.

Activate STL: Right-click an STL in the tree and choose Activate to make it the Active file or double clic on it (used for PRE-SPLIT and SPLIT). Only one file can be Active at a time. Active file is displayed in Bold
Delete: Right-click and choose Delete to remove unneeded files/folders results from the Workzone.

REPAIR (Beta)

Repairs the active mesh to improve printability (fixes holes, self-intersections, non-manifold edges, flipped normals, tiny stray shells).

Input: Active file (e.g., Demo.stl).
Output: Demo-Rep.stl added to the Workzone and shown in the tree.
Status: Beta, may still fail or under-repair in some cases; your original file is kept as a backup in the Workzone.
Known quirk (first launch): You may need to click Repair twice to trigger the action.
Best practice: If the result looks wrong, delete the repaired file.

SCALE

Scales the active model before splitting (useful to match target size or compensate for shrink).

Input: Active file (e.g., Demo-Rep.stl).
Output: Demo-Rep-Sca.stl added to the Workzone.
Modes: Percentage (%), Absolute dimension (X/Y/Z ) or Factor : eg :1.5 .
Safety: Non-destructive; creates a new step in the pipeline.
Project behavior: The current Pre-Split setup is automatically disabled before scaling, you’ll confirm the change if the scale factor is very large (> 20×).
Tip: Verify the new scaled file is Active before proceeding.

HOW IT WORKS

Input format: Enter a value with factor, unit or %, so the app can compute correctly.
Percentage: 150%
Millimeters: 855mm IMPORTANT do not forget to add mm after the value 855mm not 855
Factor (unitless): 1.5 (leave unit empty)

Per-axis inputs (X, Y, Z): You can fill 1, 2, or 3 fields.

One value only: The other axes are computed automatically to keep proportions (no deformation). (Most common case.)

Two values: The specified axes are scaled independently; the unspecified axis does not change.
Example: X=120%, Y=130%, Z= (empty) → deform X and Y, keep Z unchanged.

Three values: The part is scaled/deformed independently on each axis using the three inputs.

Mixing units is allowed:
Example: X=120%, Y=568mm, Z=1.6 (factor)

TIPS & NOTES:

Use percent for relative growth/shrink, mm for targeting a precise dimension, or factor for quick ratios.
Very large factors (> 20×) trigger a confirmation.
After scaling, a new file (e.g., *-Sca.stl) is added to the Workzone, make sure it is Active before PRE-SPLIT.

AUTOSHELL

Creates a printable shell (hollowing) on the active model with a specified wall thickness.

Input: Active file (e.g., Demo-Rep-Sca.stl).
Output: Demo-Rep-Sca-She.stl added to the Workzone.
Use cases: Reduce material, speed up print, enable lightweight parts while keeping exterior shape.
Beta note: Included in the Beta, part numbering inside AutoShell may be unavailable initially.
Workaround: If you need identification, mark parts manually after printing (pen/labels).

THICKNESS GUIDELINE

Recommendation: Avoid creating shells thinner than 15 mm to preserve enough space for tenons and tolerances.

Why: Thicker shells provide reliable tenon seating, reduce breakthrough risk, and improve bonding area.

Tip: If your tenon template is large or includes fillets/chamfers, consider ≥18–20 mm shell thickness. Adjust tenon spacing and offsets accordingly before running Split.

Of course, avoid trying to create an autoshell on small parts that are smaller than the thickness of the shell!

Position and adjust the cutting planes; use hotkeys and X/Y/Z controls to fine-tune the split configuration.

PURPOSE

PRE-SPLIT is where you configure how the model will be divided: you pick the printer constraints, define cut sizes, position the cutting planes, and (optionally) set up tenons. The resulting configuration is applied when you run Split.

1) PRINTER SELECTION

Choose the target printer profile used for this Workzone.
Sets the usable build volume (X/Y/Z) proposed in the UI.
Prevents plane positions that would generate parts larger than the printer’s capacity.
Saved in the .s3r project file so you can reopen with the same constraints.

2) CUT SIZES

Define the cut size parameters that guide how large each part can be after splitting.
Typical fields: maximum part size per axis (X, Y, Z) and optional margins.
Use these values to keep parts printable on the selected printer.
Changing cut sizes updates the recommended plane layout (you can still fine-tune manually).

3) MOVE STEP

Set the Move step (distance increment) used by the plane controls and hotkeys.
All plane moves use this step value.
Adjust it for coarse moves (large step) versus precise placement (small step).

4) TENON TYPE & TEMPLATE

Configure mechanical connectors added during Split.
Type: e.g., round, rectangular, dovetail (depends on available options).
Template: a preset with dimensions/tolerances/spacing.
You can reuse your own templates; their paths are stored in the Workzone (see .s3r).
Tenons are applied at Split time; verify clearances and wall thickness first.

5) CONTROLS & HOTKEYS

Use buttons or hotkeys to place planes exactly where you want:
Buttons: X-, X+, Y-, Y+, Z-, Z+ move the active plane along the selected axis by one Move step.
Hotkeys (numpad):
X- = 4 / X+ = 6
Y- = 2 / Y+ = 8
Z- = 3 / Z+ = 9
G (Ghost view): toggles a semi-transparent ghost display to help you see through the model and align planes/tenons more easily.

6) TYPICAL WORKFLOW

Select the printer profile.
Set cut sizes to keep parts within the printer volume.
Choose the Move step.
Position planes with X± / Y± / Z± (or hotkeys).
Pick Tenon type and Template if needed.
Run Split to generate parts (results are written to a new results_* folder).

NOTES & BEST PRACTICES

PRE-SPLIT always works on the Active file from PREPARE. Confirm it’s the one you want.

If the EXPLODE review shows issues (misplaced planes, tiny avoidable fragments), come back to PRE-SPLIT, adjust positions/sizes/templates, then run Split again.

On low-power PCs and large meshes, prefer the buttons over holding hotkeys to avoid key repeat backlogs.

Split is the operation that runs after PRE-SPLIT and before you review results in EXPLODE. It takes the Active file and your current plane configuration, computes the partitions, and writes the output to a new results folder in the Workzone folder.

Input: Active file from PREPARE + plane positions from PRE-SPLIT.
Output: A folder named like results_<active-file>.stl containing the generated parts.
Non-destructive: Your original and intermediate files remain untouched, each SPLIT is attached to the active part.
Repeatable: Adjust planes and run SPLIT again.
Performance: Split time depends on mesh complexity, number of planes, and available CPU/RAM.

Best practice: Verify the correct Active file in PREPARE, then run PRESPLIT to adjust plane position

SPLIT once you’re satisfied with plane placement.

PERFORMANCE & PARALLELISM

CPU usage: The number of cores/threads used during Split depends on your PC’s capabilities and your Parameters configuration.

Check Core: By default, Split3r set to 5 threads, you can override this in Parameters if needed. Check the number of thread available and enter the maximum number of core you want ot use.

Trade-offs: More threads can speed up computation but increase RAM usage and system load. On low-RAM or thermally constrained machines, use fewer threads for stability.

Tip: Close heavy background tasks before running Split3r to avoid contention and throttling.

Inspect, filter, and organize the resulting parts, manage visibility and bulk actions from the parts tree.

TREE MANAGEMENT

Checked = Visible. The part is shown normally in the 3D view.
Unchecked = Hidden. The part is not rendered.
Selected (in the tree) = Ghost. If a part is unchecked but selected with the mouse, it appears in a semi-transparent “ghost” display for quick inspection.

To-check folder. Contains suspicious, very small fragments automatically filtered during Split. These usually come from model geometry that produces tiny, non-useful pieces. Review and delete if not needed.

MULTI-SELECTION & CONTEXT MENU

Multi-selection in the tree

Use Ctrl-click (add/remove one item) and Shift-click (range) to select multiple parts.
Actions apply to all selected items (e.g., Delete, Check/Uncheck).

Visibility rule with selection:

Checked = Visible
Unchecked = Hidden
Unchecked but selected = Ghost (semi-transparent) for quick inspection.

Right-click on a tree label

Right-click on the text label of any item (not just the checkbox) to open the context menu.

Menu actions (as shown bellow):

Delete = remove selected file(s) from the Workzone.
Invert folder checkboxes = flip checked/unchecked for items in the current folder.
Check all = check all items in the current folder.
Check all except selection = check everything except the currently selected items.
Uncheck all except selection = uncheck everything except the currently selected items.

Tip: Combine multi-selection + right-click to perform fast bulk curation (hide tiny fragments, keep only candidates, or clean a results folder).

BUTTONS & SHORTCUTS

E = Explode. Toggles/animates the exploded view to separate parts spatially for inspection.
T = Tighten. Brings parts closer together (reverse of explode) to check fit and grouping.
L = Label displays. Shows/hides labels for parts (IDs/names) to help identification.
R = Reset to view all. Resets the camera/visibility context to show all parts clearly.

Once processing is complete, Split3r automatically saves all generated parts inside your project’s WorkZone.

Output location

Each split creates a subfolder inside the WorkZone. The subfolder is named after the STL file used for the split, with operation tags appended.

Example: results_Lambo+Rep+Sca+She

Multiple splits per WorkZone

You can run several splits from different STL files within the same WorkZone. Each run will create its own results_<STL name + tags> subfolder, so outputs remain separated and easy to identify.
<YourWorkZone>\

Lambo.stl

Lambo+Rep+Sca+She.stl
Lambo+Rep+Sca+She.s3r

results_Lambo+Rep+Sca+She\

0.0.0_1.stl

0.0.0_2.stl

...

results_Lambo\