> ## Documentation Index
> Fetch the complete documentation index at: https://docs.3dpreppro.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Advanced settings
> Fine-tune every aspect of the repair process
Click **Advanced Settings** in the repair dialog to reveal additional controls. If you're not sure about a setting, leave it at the default — the defaults work well for most models and printers.
**Default: 1.0 mm**
Sets the minimum wall thickness. Any walls thinner than this value are automatically thickened during repair.
**Recommended values:**
* FDM printers: 1.0–1.5 mm
* SLA/resin printers: 0.5–1.0 mm
* Full-color (Mimaki): 0.7–1.0 mm
Setting this below 0.5 mm may result in walls that break during printing or post-processing.
**Default: 1.5 mm** (Character 1.5, Vehicle 1.0, Mechanical 0)
Gaps between surfaces narrower than this distance are filled and fused into the output. Larger values fuse more — good for posed figures where fingers, sleeves, and props touch. Smaller values preserve narrow gaps, and 0 turns fusing off.
**Default: 0 (solid)**
Creates a hollow interior with the specified shell thickness. Set to 0 to keep the model solid.
* Saves material and reduces print cost
* 2–3 mm shell thickness works well for most full-color printers
* Make sure the shell is at least as thick as the Wall Thickness setting
Very thin shells (under 1 mm) may not be strong enough to hold their shape.
**Default: 0 (off)**
Automatically fills holes in the mesh surface up to this perimeter size. Larger values close bigger holes. Set to 0 to skip hole filling. The recommended value comes from the analyzer and is seeded automatically when you use the **Recommended** model type.
Small holes (under 10 mm) are usually modeling artifacts — close them freely. Large holes may be intentional (like the bottom of a vase).
**Default: On**
When on, the repair keeps the analyzer's recommended polygon count. Turn it off to set a custom target with the **Target Faces** slider.
The Target Faces slider ranges from **1K to 5000K** (1,000–5,000,000 faces). When you turn Smart Polygon Count off, it's seeded from the analyzer's recommendation, or an estimate based on the model's current polygon count if none is available. Reducing polygons makes smaller files that slice faster, but may lose fine detail.
* 100,000–500,000 faces is plenty for most prints
* Below 50,000 may lose visible features
**Default: On** (the Vehicle preset turns it off)
Cuts away geometry hidden behind transparent textures. Useful for VRoid hair and clothing, and for character models exported from game engines that have transparent hair cards or glass effects.
**Default: Off**
Blends textures from multiple material slots into a single unified texture. Useful when your model has many separate materials that your printer can't distinguish.
**Default: Off.** Smoothing softens the repaired surface. The master **Smoothing** toggle is off by default, so the fix keeps maximum detail. Turning it on reveals three controls and applies their recommended values; turning it back off restores the fully detailed result. The built-in Character, Mechanical, and Vehicle presets all ship with Smoothing off — it's a separate opt-in, and the **Recommended** model type (available once your model has been analyzed) turns it on automatically.
Some smoothing happens **before** the fix and some **after** it, and the two aren't interchangeable: before-the-fix smoothing relaxes your *original* model so the fix rebuilds from a softer shape (this reduces faceting everywhere, but can round genuine edges), while after-the-fix smoothing relaxes only the *rebuilt* surface (the safest, most-used control).
```mermaid theme={null}
flowchart LR
A([Your model]):::model --> B{{Pre-smoothing}}:::before
B --> C[The fix
rebuilds a clean surface]:::fix
C --> M{{Clearance smoothing}}:::during
M --> D{{Post-construct smoothing}}:::after
D --> E([Repaired model]):::model
classDef model fill:#e0e7ff,stroke:#6366f1,stroke-width:2px,color:#1e1b4b
classDef before fill:#cffafe,stroke:#06b6d4,stroke-width:2px,color:#083344
classDef during fill:#fef9c3,stroke:#eab308,stroke-width:2px,color:#422006
classDef after fill:#dcfce7,stroke:#22c55e,stroke-width:2px,color:#052e16
classDef fix fill:#f1f5f9,stroke:#94a3b8,stroke-width:2px,color:#0f172a
```
**Pre-smoothing — before the fix.** Default **Off** (turns on automatically when you enable Smoothing). Softens your *original* model before it's repaired, reducing faceting across the whole result — but it also affects edges you might want to keep. Turn it **on** for organic models (characters, figures, scans); **off** for mechanical / CAD parts. .vrm files always use the character pipeline regardless of this toggle.
**Clearance smoothing (0–256) — during the rebuild.** Default **128** (when Smoothing is on). Rounds off detail on the solid while the fix is rebuilding it; higher values remove more bumps and noise, **0** keeps the finest detail.
**Post-construct smoothing (0–50) — after the fix.** Default **8** (when Smoothing is on). Relaxes the rebuilt surface after the fix — the most commonly used control. **0** keeps fine detail; higher values give a smoother surface but soften or erase small features (wrinkles, engraving, thin relief). For medical (DICOM) models, this is raised to 30 automatically when left at 0.
**Choosing by model type**
* **Mechanical / CAD parts** — Smoothing off (or Post-construct 0–2), Pre-smoothing off.
* **Characters / figures / organic** — Smoothing on, Post-construct 8.
* **Noisy scans** — a little Clearance smoothing, plus Post-construct 8.
**Troubleshooting**
* *Too blocky or stair-stepped* — turn on Pre-smoothing and/or raise Post-construct smoothing.
* *Fine detail disappeared* — lower Post-construct and Clearance smoothing; consider turning Pre-smoothing off.
* *Sharp edges got rounded* — turn Pre-smoothing off and keep Post-construct smoothing low.