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Tangent arcs

Use the TangentLineA straight line, arc, or spline drawn in Sketch mode or on a layout plane. Lines have length but no area. When you pull a sketch into 3D with the PullTool used to distort or deform geometry. Use the Pull tool to offset, extrude, revolve, sweep, draft, and blend faces; or to round, chamfer, or extrude edges. When converting a sketch to 3D, pulling a line creates a surface and pulling a surface creates a solid. tool, lines become edges. that touches a curve (arc or circle) at only one point, without crossing over, and is perpendicular to the radius at the point of tangency. You can sketch a line tangent to a curve or you can sketch an arc tangent to a line or curve. ArcCurved line of constant radius; part of a circle. See Sweep arc, Three point arc, Tangent arc. tool to sketch an arc that is tangent to a curve or line in your design. This arc will become an edge when you pull your sketch into 3D with the Pull tool.

The sketch grid must be visible in the workspace before you can draw.

To draw a tangent arc

1. Click Tangent Arc in the Sketch group.

   The tool is disabled if there are no curves or lines in the sketch plane.

2. Click the line or curve you want to draw tangent to.

   This is usually done at the end point of a line, arc, or spline, but it can be on the line. If two lines share an end point, use the scroll wheel to set tangency to the other line.

3. (Optional) Dimension the radius and chord angle.

4. Click to set the end point of the arc.

   The arc cannot end on its start point to make a circle or end on the same line as its start point.

To draw a tangent arc between points in 3D

1. Click Tangent Arc in the Sketch group.

2. Switch to 3D mode:

   • If a sketch plane is not active, press Esc.
   • If a sketch plane is active, click 3D ModeThree ways of designing: Sketch, Cross-section, or 3D. You can switch between modes at any time. in the Mode group or press D.

3. Click to set the first point of the arc.

   This can be any point on an object in your design.

   The tangency indicator shows you how the new arc will be tangent with existing geometry if you click on the current cursor location.

4. Click to set the end point of the arc.

To edit a tangent arc

Drag the arc to edit it. When you drag a tangent arc, it increases its radius while maintaining its chord angle.

Options

The following options are available for every sketch tool:

• Cartesian dimensions: Select a point in a sketch and then click this option to see Cartesian dimensions from the point. Cartesian dimensions show you the X and Y distances from the point you select. If you don't have a point selected, it shows you the X and Y distances from the origin.

• Polar dimensions: Select a point in a sketch and then click this option to see Polar dimensions from the point. Polar dimensions show you an angle and a distance from the point you select. If you don't have a point selected, it shows you the angle and distance from the origin.

• SnapConstrain to objects, angular and linear increments, or grid points while you are sketching or editing solids. You can customize the snapping behavior in File>Options. Pressing Shift while dragging snaps the tool based on your snap settings. You can use the Snap to grid tool to constrain or lock all drawing to grid points only. to grid: Select this option turn snapping on or off while sketching. The cursor will snap to the minor grid spacing increment while you sketch. The defaults are 1mm for Metric and 0.125in for Imperial units. See Units options to change the minor grid spacing.

• Snap to angle: Select this option to turn angle snapping on or off while sketching. The cursor will snap to the angular snap increment while you sketch. The default is 15 degrees. See Snap options to change the angular increment used for snapping.

• Create layout curves: The sketch curves are created as layout curves. If you move the design to a drawing sheet, with Sketch modeMode for drawing in two dimensions using the sketching tools on the sketch grid. A sketch is a collection of lines and other 2D objects on a sketch grid. Sketching creates regions that can be pulled into 3D. When you pull your sketch into 3D with the Pull tool, regions formed by intersecting lines will become solids and lines will become edges. selected you must select the Create layout curves checkbox again in the Sketch Options group of the Options panelArea of the user interface that enables you to modify functions specific to tools. in order to create layout curves on the drawing sheet. See Layout Curves.

• CurveIn 3D, any line in space. Fitter Options: If the Sketch plane passes through a Mesh objectObjectAnything recognizable by the tools. 3D objects include vertices, edges, faces, surfaces, solids, layouts, planes, axes, and origins. 2D objects include points and lines. created by importing an STL fileFile format native to the stereo lithography CAD software created by 3D Systems. You can export parts and assemblies (.stl).See Stereo lithography. lightweight (facets only). Mesh objects have the ability to snap to the facets., the system will fit curves through the facet points. Lines are displayed green and arcs are displayed blue. The following options apply to the system-generated curves.

  • Fit curves - Uncheck this option if you do not want the system to fit curves through the points.

  • Tolerance - Determines how many points will be found, which also determines how many curves will be created. The smaller the tolerance, the more points will be found and the curves will be generated.

  • Auto-merge - When checked On, the system will merge lines and arcs to form splines. Splines are displayed pink.

Examples

Arc sketched tangent to two circles

Editing a tangent arc maintains its connections