Constraints are rules that you can define between sketches and for a sketch itself. They will help you create accurate and precise sketches.

**Using constraints**

In Shapr3D you only have to keep yourself to a small set of rules to use our constraints efficiently:

**Just start sketching:**You can access the constraints in the**Sketch**menu, just select any sketch or tap on**Sketch**and the Menu will appear.**Always pre-select**: Select the lines, points, arcs, circles first and only then add the constraints. Simple as that.**Dimension & Auto-lock:**Tap on any line, circle or combination of points and give them length, radius or create a distance between them. These dimensions will be auto-locked.

**TIP: Create a rough sketch first and only then add constraints. This workflow will make your job easier!**

**Edge - sketch constraints**

You can define constraints between edges of bodies and sketches

**How can I delete constraints?**

- Select the sketch you want to modify
- Tap on the constraint icon you want to delete
- Tap on the "X"

**List of available constraints:**

**Parallel: **It makes 2 or more lines parallel to each other.

**Perpendicular: **It creates a 90**° **connection between 2 or more lines. The lines don't have to share a common point or intersect with each other.

** Tangent: **You can make a circle&circle; line&circle and a line&line tangent to each other.

**Concentric: **It makes two or more circles share their center point.

**Horizontal / Vertical: **This command will make your lines parallel to the X or Y axis of the sketch plane, whichever takes fewer adjustments.

**Equal: **Makes your lines the same length and your circles having the same radius.

**Lock: **It locks your points. Select any number of lines, circles or points and this tool will lock all the points related. Locking a single point can be achieved by selecting the point and tapping on the lock icon on top of it.

**Symmetry: **Makes your lines, circles or points symmetric to each other, in relation to a given axis.

- Lines: The vectors will be mirrored to a given axis
- Circles: The radius will remain the same, and the center point will be on the same imaginary line, perpendicular to the axis of symmetry.

**Dimensions **

There are multiple dimensions you can select by simply tapping on the sketch you want to change, and entering chosen dimension. Here are the options you have:

- length: select a line, tap on the annotation and enter the value

- radius: select a circle or an arc, tap on the annotation and enter a value

- angle: you can set the angle between two connected curves. You can modify the angle by selecting the two lines/arcs, tapping on the annotation and entering the final angle.

- point-to-point distance: Define the distance between two points by selecting them, and entering the desired length. 3 different distances are available:

- Absolute
- Horizontal
- Vertical

- point-to-line distance: Define the length between a point and a line

**Tutorial**

In this video you can learn how to use all the tools mentioned in this article, and learn finishing up your sketches with constraints.