To Change a Part's Position and Orientation

Equate Alignment dialog box for Part moved on machine

For Equate Alignment to function properly, the features referenced in your new alignment must be measured after you move your part. Those features must reside in the measurement routine below the commands that are executed in the part's original position and orientation (including the original alignment). Additionally, you should reference all of the features for your new alignment in a single alignment block. The new alignment should be fully constrained.

This command works with both regular alignment blocks (START_ALIGN/END_ALIGN pairs) and external recalled alignments. The external alignment must be recalled using the RECALL/ALIGNMENT, EXTERNAL command before it becomes available for use in the dialog box.

Equate new alignment:

This list allows you to select the new alignment you are equating with your original created alignment.

With original alignment

This list allows you to select a the previously created original alignment to which you are equating the new alignment.

For example, to measure a dimension that references features on two sides of the part that are not accessible from a single part orientation:

  1. Measure the alignment features on the first side of the part.

  2. Create the original alignment.

  3. Measure all required features that can be reached from the first orientation of the part.

  4. Move the part to its new position.

  5. Measure the new alignment features. The origin must be the same and the axis must be in the same direction as the axis of the alignment to which you are equating. It is easiest to understand this if you imagine that the original origin and axes' arrows are glued onto the part before moving it. The new alignment places the origin and axes' arrows in the same position with respect to the part.

  6. Select the Insert | Alignment | Equate menu option. The Equate Alignment dialog box appears.

  7. In the Equate Type area, select Part moved on machine. Note that when editing an existing Equate alignment command, the Equate Type area is disabled.

  8. In the Equate new alignment list, select the new alignment.

  9. In the With original alignment list, select the original alignment.

  10. Click the OK button to insert the new EQUATE alignment command into the measurement routine. The CAD model won't move relative to the alignment axes, but the measured values will move once PC-DMIS executes the equate alignment.

The Edit window command line for this option reads:

EQUATE/"name1"TO ALIGNMENT,"name2"

Note about Clearance Planes

After equating the new alignment, any existing clearance planes continue to use the same "relative" plane from the previous alignment. This means after you've moved your part, you should define new clearance planes to avoid incorrect clearance plane moves.