---
title: Rounding & Blending
order: 5
---

Chisel uses the same five-profile system everywhere fillets exist: primitive edge rounding, boolean blends, mirror seams, array seams, prism bevels, emboss inner corners. Pick the profile, set the radius, done.

## What's the difference?

**Rounding** is the radius applied to the edges of a *single primitive*. Set it on the primitive and every applicable edge softens.

**Blending** is the radius applied at the *seam where two shapes meet*: booleans, mirrors, arrays, emboss/engrave. Set it on the modifier and the join becomes a smooth fillet.

Both use the same five profiles and the same numeric range. The only difference is whether they live on the primitive or on the modifier.

**Smooth** is the third layer: one [Smooth modifier](../modifiers/smooth.md) sets a radius for the *whole model*. Every join, edge and bevel sharper than it rounds up to it, and anything you already made rounder keeps its own value.

## Topics

- **[Profiles](profiles.md)**: the five fillet shapes (Round / Sharp / Soft / Tight / Chamfer) explained
- **[Rounding](rounding.md)**: primitive edge rounding workflows and parameters
- **[Blending](blending.md)**: modifier-seam blending across booleans, mirrors, arrays

## Where each setting lives

| Surface | Setting |
|---|---|
| Primitive edges | Object Properties → SDF → *Rounding* + *Profile* |
| Ngon corners | Object Properties → SDF → per-point *Rounding* + *Profile*, or the orange gizmo handles |
| Boolean seam | Modifier panel → Boolean → *Blend Radius* + *Blend Profile* |
| Carve edge | Modifier panel → Carve → *Blend* + *Outer* + *Profile* |
| Bisect cut edge | Modifier panel → Bisect → *Blend*, or the orange ring gizmo |
| Bisect polyline corners | Modifier panel → Bisect → *Corner Blend* per plane, or the orange corner dots |
| Mirror plane | Modifier panel → Mirror → *Mirror Blend* |
| Array seam | Modifier panel → Array → *Smooth* |
| Emboss outer seam | Modifier panel → Emboss → *Blend Radius* + *Profile* |
| Emboss inner corner | Modifier panel → Emboss → *Inner Radius* + *Inner Profile* |
| Sweep path corners | Modifier panel → Sweep → per-point *Rounding*, or the orange gizmo handles |
| Prism / Trapezoid / Oblong vertical edges | Object Properties → SDF → *Bevel* + *Bevel Profile* |
| The whole model | Modifier panel → [Smooth](../modifiers/smooth.md) → *Radius* + *Profile* |