Defining Additional Constraints for an Arc

Access: Invoke the Sketcher, define the sketch plane and then invoke this function from one of the following locations:

Click the Arc button in the Sketcher toolbar.
Right-click the graphics area and select Arc from the popup menu.

Create an arc.

As you create a new arc, you can relate the arc to additional entities in the graphics display area. For example, you can create a new arc that is tangent to existing entities, or you can create a copy of an arc that is also tangent to another existing arc. After this is done, all the entities are mutually constrained.

First, define the image of a new arc as described in step 1 below.
Then, define an additional constraint for the new arc as described in steps 2 to 4.
Click to define the arc. (If the arc is fully constrained, it is defined automatically.)

Note: If you want to constrain arcs to entities that are not in the current sketch, you must add the entities to the sketch as reference entities.

To define additional constraints on a new arc:

Create a new arc using any of the Arc options (Center, Pt, Diameter or Tangent). An image of the new arc appears in the graphics display area. You can now constrain the new arc relative to an existing entity.

Right-click to display the popup menu and choose a drawing option.
Click an existing entity in the graphical display area.

The new arc will be constrained to the entity selected in step 3, according to the option selected in step 2.

You can repeat steps 2 and 3 to define additional constraints.
Click to define the new arc.

For example, you can create an arc that is tangent to three entities, as follows:

Right-click and choose Tangent. Create the new arc tangent to an existing line. An image of the new tangent arc appears.

Right-click and choose Tangent again to constrain the new arc (by making it tangent to another existing arc).
Select an existing arc.

The new arc is now tangent to the line selected in step 1 and tangent to the existing arc selected in step 3.

Define a third constraint: Right-click and choose Tangent. Then, select a line (line 3).

The new arc is now tangent to three entities.

Note: Because the new arc is fully constrained, the arc is defined automatically.

Note: When you define additional constraints, the new entity will be constrained to an existing entity, a mutual constraint relationship is created with the existing entity. If required, you can subsequently break an entity's constraints to make it independent of all other entities and the XY axis.