Protractor Tool

Use the Protractor Tool to measure angles and create angled guide lines. Activate the Protractor Tool from the Construction Toolbar or the Tools menu.

Measuring an Angle

Measure an angle when you want to duplicate that angle elsewhere in your model or create plans, such as for a woodworking project. To measure and an angle:

1. Select the Protractor Tool. The cursor will change to a protractor, aligned to the red/green plane and with its center point fixed to the cursor.
2. Place protractor's center at a vertex of the angle (where two lines meet).

3. Click to set the vertex of the angle you will measure. The following image shows the protractor being placed at the angle's vertex.

4. Move the cursor in a circle until it is touching the start of the angle (one of the lines). The following image shows the first line in the angle (from the vertex out along to the red square).

5. Click to set the start of the angle.
6. Move the cursor in a circle until it is touching the end of the angle (other line). Notice that the protractor has marks, indicating 15 degree increments, on its edge. The angle will snap to these tick marks when the cursor is close to the protractor while moving around the protractor. Conversely, angle will move in more precise (smaller) increments when your cursor is farther from the center of the protractor while moving around the protractor.

Note - Press the Esc key at any point during the operation to start over.

7. Click to measure angle. The angle's measurement will appear in the VCB. The value displayed in the VCB is referred to as the angular rotation value. The following image shows the second line in the angle (from the vertex out along to the red square). The angle measures 120 degrees.

Note - Set the angle manually by entering a value in the VCB, and pressing Enter. The value can either be in decimal degrees, such as 34.1,  or slope, such as 1:6. This value can be changed any number of times before proceeding to the next command.

Creating Angled guide lines

Angled guide lines are useful to draw angled geometry such as a roof slope. To create an angled guide line:

1. Select the Protractor Tool. The cursor will change to a protractor, aligned to the red/green plane and with its center point fixed to the cursor.
2. Place protractor's center at a vertex of the angle.
3. Click to set the vertex of the angle you will measure. The following image shows the protractor being placed at the angle's vertex.

4. Move the cursor in a circle until it is touching the start of the angle (one of the lines). The following image shows the first line in the angle (from the vertex out along to the red square).

5. Click to set the start of the angle.
6. Press and release the Ctrl key.
7. Move the cursor in a circle until the guide line is at the desired angle. Notice that the protractor has marks, indicating 15 degree increments, on its edge. The angle will snap to these tick marks when the cursor is close to the protractor while moving around the protractor. Conversely, angle will move in more precise (smaller) increments when your cursor is farther from the center of the protractor while moving around the protractor.

Note - Press the Esc key at any point during the operation to start over.

8. Click to create the guide line. The following image shows a guide line created at a 45 degree angle so that a profile of a roof can be drawn.

Entering Exact Angular Values

The degree of rotation you have indicated appears in angular degrees in the VCB while creating guide lines using the Protractor Tool. You can also manually enter in angular rotation or slope values directly into the VCB while measuring an angle and setting a guide line.

Entering an Angular Rotation Value

To specify an exact angle in degrees, type a decimal value into the VCB while rotating the cursor around the protractor. For example, typing in 34.1 will give you an exact 34.1 degree angle. Negative values will move angle in a counter-clockwise direction. You can specify an exact angular value either during or immediately after your rotation operation.

Entering a Slope Value

To specify a new angle as a slope, type in the two values separated by a colon in the VCB, such as 8:12. Negative values will move angle in a counter-clockwise direction. You can specify an exact angular value either during or immediately after your rotation operation.

Note - SketchUp can handle up to 0.1 of a degree of angular precision.

Locking the Protractor Tool to its Current Orientation

Press and hold the Shift key, before you click on an entity, to lock the operation to that orientation.