Arc & Full Circle

Arcs and full circles are available for placement in both the PCB and PCB library editors. 

• In the PCB editor:
  • Choose Home | Place | Arc from the main menus then select the required placement mode from the sub-menu.

• Choose Home | Place | Full Circle from the main menus to place a full circle.

• In the PCB library editor:
  • Choose Home | Place | Arc from the main menus then select the required arc mode or Full Circle from the sub-menu.

• Right-click in the design space then choose Place » Arc (Center), Arc (Edge), Arc (Any Angle), or Full Circle.

The way in which an arc is placed depends on the particular method of placement that you have chosen to invoke. Four different methods of arc placement are supported:

• Arc (Center) – this method enables you to place an arc object using the arc center as the starting point.
• Arc (Edge) – this method enables you to place an arc object using the edge of the arc as the starting point. The arc angle is fixed at 90°.
• Arc (Any Angle) – this method enables you to place an arc object using the edge of the arc as the starting point. The angle of the arc can be any value.
• Full Circle – this method enables you to place a 360° (full circle) arc.

Placing an Arc Starting at the Center

After launching the command, the cursor will change to a cross-hair and you will enter arc placement mode. Placement is made by performing the following sequence of actions:

1. Click or press Enter to anchor the center point of the arc.
2. Move the cursor to adjust the radius of the arc then click or press Enter to set it.
3. Move the cursor to adjust the start point for the arc then click or press Enter to anchor it.
4. Move the cursor to change the position of the arc's endpoint then click or press Enter to anchor it and complete placement of the arc.
5. Continue placing further arcs or right-click or press Esc to exit placement mode.

Placing an Arc Starting at the Edge

After launching the command, the cursor will change to a cross-hair and you will enter arc placement mode. Placement is made by performing the following sequence of actions:

1. Click or press Enter to anchor the start point for the arc.
2. Move the cursor to change the position of the arc's endpoint then click or press Enter to anchor it and complete placement of the arc.
3. Continue placing further arcs or right-click or press Esc to exit placement mode.

Placing an Arc Starting at the Edge (any angle)

After launching the command, the cursor will change to a cross-hair and you will enter arc placement mode. Placement is made by performing the following sequence of actions:

1. Click or press Enter to anchor the start point for the arc.
2. Move the cursor to adjust the radius of the arc then click or press Enter to anchor the center point.
3. Move the cursor to change the position of the arc's endpoint then click or press Enter to anchor it and complete placement of the arc.
4. Continue placing further arcs or right-click or press Esc to exit placement mode.

Placing a Full Circle 

After launching the command, the cursor will change to a crosshair and you will enter arc placement mode. Placement is made by performing the following sequence of actions:

1. Click or press Enter to anchor the center point of the circle.
2. Move the cursor to adjust the radius of the circle then click or press Enter to set it and complete placement of the circle.
3. Continue placing further circles or right-click or press Esc to exit placement mode.

Additional Placement Actions

Additional actions that can be performed during placement are:

• For all methods (except full circles), press the Spacebar before defining the arc's endpoint to render the arc in the opposite direction.
• Press the L key to flip the arc to the other side of the board. Note that this is only possible prior to anchoring the arc's start/center point.
• Press the + and - keys (on the numeric keypad) or use the Shift+Ctrl+Wheelroll shortcuts to cycle forward and backward through all visible layers in the design to change the placement layer quickly.
• Press the Tab key to open the Arc mode of the Inspector panel in which properties for the arc can be changed on-the-fly. When this is done, interactive editing will pause so that the panel can be used, click the pause button () that appears in the center of the design space to return to the interactive arc placement mode or press Esc.

Graphical Editing

This method of editing allows you to select a placed arc/full circle object directly in the design space and graphically change its size, shape or location.

When an arc/full circle object is selected, the following editing handles are available:

• Click and drag A to adjust the radius.
• Click and drag B to adjust the endpoints (start and end angles).
• Click anywhere on the arc/full circle away from editing handles then drag to reposition it. Alternatively, click and drag on the arc/full circle center point. While dragging, the arc/full circle can be rotated or mirrored:
  • Press the Spacebar to rotate the arc counterclockwise or Shift+Spacebar for clockwise rotation. Rotation is in accordance with the value for the Rotation Step, defined on the PCB Editor – General page of the System Preferences.
  • Press the X or Y keys to mirror the arc along the X-axis or Y-axis.

Non-Graphical Editing

This method of editing uses the Inspector panel to modify the properties of an Arc object. 

During placement, the Arc mode of the Inspector panel can be accessed by pressing the Tab key. Once the Arc is placed, all options appear.

After placement, the Arc mode of the Inspector panel can be accessed in one of the following ways:

• If the Inspector panel is already open, select the Arc object.
• With the arc selected, choose View | PCB | Inspector from the main menus.   

PCB Editor object properties are definable options that specify the visual style, content and behavior of the placed object.

Location  

The lock icon to the right of this region must be displayed as  (unlocked) in order to access these fields. Toggle the lock/unlock icon to change its lock status.

• (X/Y) 
  • X (first field) - this field shows the current X position of the center of the arc relative to the current origin. Edit the value in the field to change the position of the arc relative to the current origin. The value can be entered in either metric or imperial; include the units when entering a value whose units are not the current default. Default units (metric or imperial) are determined by the Units setting in the Other region of the Inspector panel in Board mode (accessed when no objects are selected in the design space), and are used if the unit is not specified. 
  • Y (second field) - this field shows the current Y position of the center of the arc relative to the current origin. Edit the value in the field to change the position of the arc relative to the current origin. The value can be entered in either metric or imperial; include the units when entering a value whose units are not the current default. Default units (metric or imperial) are determined by the Units setting in the Other region of the Inspector panel in Board mode (accessed when no objects are selected in the design space), and are used if the unit is not specified. 

Properties

• Net - use the drop-down or click  to select the net to which this arc belongs. All nets for the active board design will be listed in the drop-down list. Note that if object placement commences at the same location as an existing object that is already connected to a net, then the Net property of the new object is automatically assigned to that net. Select No Net to specify that the arc is not connected to any net. The Net property of a primitive is used by the Design Rule Checker to determine if a PCB object is legally placed. Alternatively, you can click  to select a specific net in the design space.
• Layer - displays the layer to which the arc is currently assigned. Arcs can be assigned to any available layer. To change the assigned layer, click the field then select a layer from the drop-down. 
• Width - displays the width of the arc line. Enter a different value for the width if required.
• Radius - displays the radius of the arc measured from the center point to the center of the arc line. Enter a different value for the radius if required.
• Start Angle - displays the start angle of the arc measured from the X-axis in the first quadrant (plane geometry). Enter a different value for the start angle if required.
• End Angle - displays the end angle of the arc. Enter a different value for the end angle if required.
• Propagation Delay - displays the time it takes for a signal to propagate along that route. 

Paste Mask Expansion

• Rule - select to have the paste mask expansion for the arc follow the defined value in the applicable Paste Mask Expansion design rule. The associated expansion value will be disabled if this option is chosen.
• Manual - select to override the applicable design rule and specify the paste mask expansion value for the arc in the field below. 

Solder Mask Expansion

• Rule - select the checkbox to have the solder mask expansion for the arc follow the defined value in the applicable Solder Mask Expansion design rule. The associated expansion value will be disabled if this option is chosen.
• Manual - select the checkbox to override the applicable design rule and specify the solder mask expansion value for the arc in the field below.