Stock Offset Point (SOP)

A Stock Offset Point (SOP) allows a routing path, made up of connected segments, to change according to the value of an expression string. This expression string may include a special routing variable standing in for the diameter of the largest stock that is assigned to that path. The path updates in response to changes to stock diameter or any other parameter included in the driving expression string.

A stock offset point (SOP) is similar to a regular offset point except that the offset distance can also be driven by stock diameter. A stock offset point is defined by an offset vector and an offset distance (expression string), relative to an origin point. An SOP is not displayed. Use the standard Point and Vector Tools to define the origin point and offset direction respectively.

The offset distance expression may include a special variable — MAX_PATH_STOCK_DIA — that takes the value of the diameter of the largest stock, including overstock, assigned to any segments passing through or ending at the SOP. For non-circular stock, the diameter value used is the value of the DIAMETER characteristic assigned to the stock. The value of the special MAX_PATH_STOCK_DIA variable is maintained automatically by Routing for each SOP.

There is no stock from which to derive a distance for the SOP until stock is assigned to a path through it. This may result in the offset distance being equal to zero, in which case the SOP position is simply coincident with its origin point. However, you can avoid this circumstance by defining the distance expression so that it always has a non-zero value. For example, using standard expression syntax:

if (MAX_PATH_STOCK_DIA>0) (MAX_PATH_STOCK_DIA/2) else (2)

This results in the distance being equal to half the stock diameter when that diameter is greater than zero, but equal to 2 when the stock diameter is zero.

Port SOP definition

Any port (fitting, fixture, or a multiport) may have its position defined in terms of an SOP. This allows the size of the stock(s) assigned to a segment routed to or through the port to determine the position of the port. Since a path segment may be defined in terms of the port (by selecting the port during a Create Linear Path or Heal Path operation), the path itself updates when the port position updates.

Example: a simple clip (typically taped onto a wire bundle) defines the position of the clip's fixture port in terms of an SOP. You must place the component into the routing assembly by a Place Part operation — Place Part performs the necessary functions to maintain the relationship between the Port position and its SOP according to the Distance Expression of the SOP. You can select the displayed port to create path segments (either through Simple or Heal Path methods). When stock is assigned to that path, the port changes position accordingly (provided MAX_PATH_STOCK_DIA is included in the Distance Expression of the SOP) and the path changes to follow the port to the new position.

Related topics

• Stock, Recreate Inaccessible Stock Components, Upgrading pre-NX 10 stock, Merge Stocks, Space Reservation, Overstock, Overstock on Fittings, Stock Style, Edit Stock Characteristics, Convert stock features to component objects, Align Stock
• Removing stock, Replace Stock