Creating Hatch Pattern

Hatch patterns can be created from a wide range of existing drawing entities. In addition, advanced formatting options let you control the pattern resolution and spacing between each pattern repetition.

• Draw an approximation of your pattern, using standard AutoCAD draw commands. This can include Line, Pline, Point, Arc, Circle, Ellipse etc – even blocks!
• Select the Create button under the Hatch Descriptions heading from the main display.
• Next, specify the pattern Lower Left Corner and Upper Right Corner. This forms a crossing selection (a rectangular area drawn to select objects fully or partly within its borders) – also see explanation of Clip Object Extents option below.
• From the Create New Pattern dialog, enter a name and description for the hatch pattern.

You can control the spacing between each repetition of the hatch pattern with Hatch Spacing. Setting the value to 1 will generate a space equal to the size of the pattern, applied to all four sides. The range is limited to 0-255 and is set to 0 by default (no spacing). Values within the range can also be set to one decimal point e.g. 0.5.

The Clip Object Extents option relates to the way entities you select are processed during hatch pattern generation. If this option is on, the selection rectangle you specified in point 3 above, will be re-sized (if necessary) to the precise extents of the entities selected. This simplifies entity selection and means you do not have to manually locate and snap to the entity extents yourself. Alternatively, with the Clip Object Extents option turned off, any free space between the selection rectangle you specify and the entities will be used to determine the hatch spacing between each pattern repetition.

You can also increase or reduce the Curve Steps by moving the slider – this option relates to the way in which curved entities such as arcs, circles and ellipses are represented within the hatch pattern. Increasing this value can create shapes that are more accurate representations of the selected curved entities.

• Click on the OK button and wait for the hatch pattern definition to be generated – this may take a few seconds.
• Next, a dialog is displayed prompting for the Preview Image Scale. If you are satisfied with the image click Accept. Otherwise, pick Define Image Scale, enter an alternative numerical value (non-zero) in the text box and click Retry. You can repeat this process until you are satisfied with the preview image.

Hatch Manager will automatically generate the pattern and zoom in around the selected objects to create the preview image.

Notes

• AutoCAD currently does not support Spline or Text entities for hatch pattern creation. Curved entities increase processing time, please be patient as this can take some moments.
  
• All entities selected for hatch pattern creation must lie in the current UCS plane. Blocks must be uniformly scaled.

Troubleshooting

• The file size of hatch patterns can increase substantially when derived from entities where circles and/or arcs are present. To reduce pattern file size, replace circles and/or arcs with short line segments where possible.
  
• When hatching boundaries that are located a long distance from the current UCS origin, patterns may appear to ‘break apart’. This is a known issue within AutoCAD. In order to avoid this, temporarily set the UCS origin close to the proposed boundary by typing UCS followed by MOVE at the AutoCAD Command line. You can then set the UCS origin back to its default location once the pattern has been successfully generated.
• Occasionally, the default pattern scale of 1.0 in the AutoCAD Boundary Hatch dialog generates the error message 'Hatch spacing too dense, or dash size too small'. This can be remedied by changing the AutoCAD HPSCALE system variable from its default value of 1.0 to an alternative value such as 0.1.