# ⚙️ Blender Workspace and Real-World Scale for Jewelry

## Learning Objectives

By the end of this 20 minute lesson you will be able to:

- Identify the main areas of the Blender interface and what each one is for.
- Set the scene units to millimeters and explain why jewelry modeling needs them.
- Adjust viewport clipping so a 1 mm prong does not disappear while you work.
- Configure snapping to a fixed millimeter increment and read exact object dimensions.
- Save a jewelry-ready startup file that you will reuse for the capstone piece.

## Quick Review: What You Already Bring

You do not need any Blender experience for this lesson. The only thing you need to remember is the finish line: a photorealistic render of your capstone jewelry piece for a portfolio or a shop listing. Everything we set up today exists to make that render accurate and repeatable.

## Theory: Units, Viewport, and Precision

### The workspace in one minute

When Blender opens, you see five areas that matter right now:

| Area | Where it is | What you use it for |
| --- | --- | --- |
| 3D Viewport | Center | Modeling and inspecting your jewelry |
| Toolbar | Left edge of viewport (toggle with `T`) | Move, rotate, scale, add objects |
| Sidebar / N panel | Right edge of viewport (toggle with `N`) | Exact dimensions, clipping, cursor values |
| Outliner | Top right | List of every object in the scene |
| Properties editor | Bottom right | Scene settings, units, modifiers, materials |

The default startup scene contains a cube, a camera, and a light. You can delete all three later; for now they are useful for testing scale.

> [!NOTE]
> If you prefer the shortcut layout used by other 3D programs, choose **Edit ▸ Preferences ▸ Keymap ▸ Industry Compatible**. This lesson uses the default Blender keymap, so stick with the default until you are comfortable.

### Set the unit system to millimeters

Open **Properties ▸ Scene Properties (the printer icon) ▸ Units** and set:

- **Unit System:** Metric
- **Length:** Millimeters
- **Unit Scale:** 1.0

Now ==1 Blender unit equals 1 millimeter==. That is the single most important setting in this lesson, because in jewelry you will constantly type values like 0.8 mm for a prong tip or 16.5 mm for a ring's inner diameter. In the default meter setup those become 0.0008 and 0.0165, which is slow to type and easy to mistype.

Leave **Unit Scale** at 1.0. It is a scene-wide multiplier, not a scale tool. Changing it here will silently break any measurement you already trusted.

### Fix the viewport clipping

Blender stops drawing geometry that is closer than **Clip Start**. The default is 0.01 m, which is 10 mm. In a scene measured in millimeters, you will zoom in toward a 0.8 mm prong, and the front of the object will vanish. That is not a modeling error, it is clipping.

Fix it once, per scene:

1. Press `N` to open the sidebar.
2. Go to the **View** tab.
3. Set **Clip Start** to `0.001 m` (1 mm) and **Clip End** to `10 m`.

> [!WARNING]
> Do not set Clip Start to 0.000001 or similar. Very small clip values cause depth flickering and z-fighting when surfaces are close together, which is exactly the situation inside a stone setting.

### Snap with real values

Press `Shift+Tab` to toggle snapping on and off. In the snapping menu at the top of the viewport, the useful options for jewelry are:

- **Increment:** moves in fixed steps. Set the step in **Viewport Overlays ▸ Snap ▸ Move Increment** (for example 0.25 mm) so a prong can be nudged by exactly a quarter millimeter.
- **Absolute Grid Snap:** snaps to grid intersections rather than to steps measured from where you started dragging. Use this when you want mirrored parts to land on the same coordinates.
- **Vertex / Edge / Face:** snaps to existing geometry. This is how you seat a bail flush against a pendant body in a later lesson.

### Overlays that matter for small objects

Press `Shift+Alt+Z` to toggle all overlays. Inside **Viewport Overlays**, turn on:

- **Statistics:** shows vertex and face counts, useful for keeping a printable model lean.
- **Text Info:** shows your object's name and current transform in the corner.
- **Cursor Location:** shows where the 3D cursor sits.

Two more habits: `Numpad 1 / 3 / 7` gives you front, side, and top orthographic views, and `Numpad 5` switches between orthographic and perspective. `Numpad .` frames the selected object. In a millimeter scene, that last shortcut is how you get back after zooming into a prong.

## Worked Examples

### Example 1: Verify that one unit is one millimeter

Add a default cube, press `N`, and look at **Item ▸ Dimensions**. After the unit change it reads 2 m, meaning 2000 mm, which is far too big for jewelry. Type `6.5 mm` into the X dimension, then `6.5 mm` in Y and `3 mm` in Z, pressing `Enter` after each. The cube is now the size of a 6.5 mm round gemstone blank. If your dimensions show something else, your Length or Unit Scale setting is wrong.

### Example 2: Confirm clipping is fixed

Zoom toward the cube until you are inside it. If the near surface stays visible, Clip Start is correct at 0.001 m. If the surface tears open and you see through the back, lower Clip Start.

### Example 3: Snap a prong position exactly

Turn on snapping with `Shift+Tab`, choose **Increment**, and set Move Increment to 0.25 mm. Select an object, press `G` then `X`, and drag. The object now moves in quarter-millimeter steps, so the readout in the sidebar shows numbers you can trust instead of 2.8834.

## Guided Practice: Set Up Your Capstone Workspace

This is the first step of your project thread. Today you are not modeling the piece yet; you are building the workshop you will model it in.

```steps
1. Open Blender, go to Scene Properties ▸ Units, set Metric, Millimeters, Unit Scale 1.0.
2. Open the N panel, View tab, set Clip Start to 0.001 m and Clip End to 10 m.
3. Set snapping to Increment and Move Increment to 0.25 mm.
4. Turn on Overlays: Statistics, Text Info, Cursor Location.
5. Select the default cube and set its dimensions to 16.5 mm x 16.5 mm x 1.6 mm. This matches a typical ring's inner diameter and band thickness.
6. Check that the dimensions read correctly in the sidebar, then delete the cube.
7. Save your setup with File ▸ Defaults ▸ Save Startup File so every future session begins in millimeters.
```

<details><summary>Click to reveal the check answers</summary>

- **A ring band thickness of 1.6 mm** should appear as 1.6 mm in the Dimensions field, not 0.0016.
- **If your cube looks enormous and the grid is unusable**, you almost certainly left Length on Meters. Recheck Unit Scale too.
- **If part of the cube vanishes when you zoom in**, Clip Start is still at 0.01 m.
- **If snapping jumps in whole units**, Move Increment is at its default of 1.0, not 0.25.

</details>

```glossary
[
  { "term": "Unit Scale", "definition": "A scene-wide multiplier applied on top of the unit system. Keep it at 1.0 for jewelry work." },
  { "term": "Clip Start", "definition": "The distance from the camera at which the viewport stops drawing geometry. Lower it to 0.001 m for millimeter scenes." },
  { "term": "3D Cursor", "definition": "The placement point for newly added objects. Move it with Shift+Right-click or the Shift+S snapping menu." },
  { "term": "Move Increment", "definition": "The step size used when snapping is set to Increment, for example 0.25 mm." },
  { "term": "Absolute Grid Snap", "definition": "Snaps to grid intersections instead of steps measured from the drag start point." },
  { "term": "N panel", "definition": "The sidebar holding exact transforms, dimensions, viewport clipping and cursor coordinates." }
]
```

## Expert Corner

- **Type values instead of dragging.** Click a dimension field and type `0.8 mm`. Dragging is for composition, typing is for accuracy.
- **Apply scale before you detail.** Select an object and press `Ctrl+A ▸ Scale` before adding bevels or modifiers, otherwise a bevel width of 0.3 mm will not be 0.3 mm.
- **One scene, one unit system.** Mixing a millimeter scene with a meter-scale imported asset is the most common cause of a ring that is suddenly a meter wide.
- **Save the startup file after every preference change**, not just once. It costs two seconds and saves a re-setup every session.
- **Avoid sub-millimeter grid work.** If you find yourself needing 0.05 mm precision to see a shape, you are usually over-detailing a form that will be smaller than a pixel in the final render.

## Summary and Next Steps

You now have a workspace that thinks in millimeters: scene units set to Metric and Millimeters at Unit Scale 1.0, clipping lowered so tiny prongs stay visible, snapping set to a 0.25 mm step, and a saved startup file you will reuse for the capstone. That combination is what separates a jewelry model that renders accurately from one that looks approximately right.

In the next lesson, **The Hard-Surface Toolkit: Loop Cuts, Bevel, Subdivision**, you will use this calibrated workspace to cut clean loops into a ring band and bevel edges to a real-world 0.3 mm radius.

```flashcard
[
  { "front": "Which settings change Blender's scene to millimeters?", "back": "Scene Properties ▸ Units: Unit System Metric, Length Millimeters, Unit Scale 1.0." },
  { "front": "Why model jewelry in millimeters instead of meters?", "back": "Real values like 0.8 mm prongs and 16.5 mm ring diameters are typed and read directly, with no tiny decimals." },
  { "front": "What must Unit Scale stay at for jewelry work?", "back": "1.0, because it is a scene-wide multiplier that silently changes every measurement." },
  { "front": "Which viewport setting makes a 1 mm prong invisible when you zoom in?", "back": "Clip Start. Lower it to about 0.001 m in the N panel ▸ View tab." },
  { "front": "Shortcut to toggle snapping on and off?", "back": "Shift+Tab." },
  { "front": "Where do you type an exact object dimension?", "back": "N panel ▸ Item ▸ Dimensions." },
  { "front": "Which shortcut frames the selected object in the viewport?", "back": "Numpad period (Numpad .)." },
  { "front": "What does the 3D cursor do, and how do you move it?", "back": "It is the insertion point for new objects; move it with Shift+Right-click or the Shift+S menu." },
  { "front": "Shortcut to open the sidebar with dimensions and clipping?", "back": "N. The toolbar on the left is T." },
  { "front": "Shortcut to toggle all viewport overlays?", "back": "Shift+Alt+Z." },
  { "front": "What does Ctrl+A ▸ Scale do, and why apply it before detailing?", "back": "It bakes object scale into the mesh so bevel widths and modifiers are uniform and true to size." },
  { "front": "What is the difference between Increment and Absolute Grid Snap?", "back": "Increment moves in fixed steps from the drag start; Absolute Grid Snap locks to grid intersections." },
  { "front": "What three objects are in Blender's default startup scene?", "back": "A cube, a camera, and a light." },
  { "front": "How do you make your millimeter setup the default for every new file?", "back": "File ▸ Defaults ▸ Save Startup File." }
]
```

```cloze
In Scene Properties ▸ Units, set Unit System to {{c1::Metric}} and Length to {{c2::Millimeters}}, keeping Unit Scale at {{c3::1.0}}.
To keep a 1 mm prong visible while zooming in, lower the viewport Clip Start to about {{c4::0.001 m}}.
Pressing {{c5::Shift+Tab}} toggles snapping, and the step size for Increment snapping is set under Viewport Overlays ▸ Snap ▸ Move Increment.
Before adding bevels, press {{c6::Ctrl+A then Scale}} so that the mesh carries no leftover object scale.
```