#### Setting Boundary Points Using the CAD Data Method

PC-DMIS allows the selection of boundary points using both wire frame and surface data.

When using CAD surface data:

1. Make sure that you have imported solid CAD data.

2. Make sure that the Draw Surfaces icon is selected from the Graphics Modes toolbar.

3. Select a boundary point by clicking on the desired location in the Graphics Display window.

The selected surface will be highlighted. PC-DMIS will then automatically update the value of the Boundary point that is currently selected in the boundary list. The focus will then move to the next boundary point (if any are available). In the case of a PATCH scan, an extra boundary point will be added automatically if the current point is the last point in the list.

When using CAD wire frame data, there are two modes of selecting Curve elements:

Wire Frame Data Mode 1
Depth Curve

A Depth Curve is used by PC-DMIS during FindNoms operations to form a plane using two curves. Ideally, the Depth Curve is normal to the other Curves selected so that PC-DMIS can cross the two vectors (vector of the Depth Curve and vector of any other selected curve) and form a plane from which it can find the nominals.

To indicate a Depth curve, check the Depth check box and then select a curve. Only one Depth curve is to be selected and this should be done after other curves have been selected.

1. Make sure that the Curve mode icon is selected from the Graphics Modes toolbar.

2. Select the Select check box.

3. Select the Depth check box.

4. Select a curve.

5. Indicate the two CAD edges that are normal to each other.

6. Clear the check box.

7. Click on the part.

If a Depth curve is provided, PC-DMIS will form a plane by crossing the vector of each edge with the vector of the depth curve and piercing that plane to create a point.

Wire Frame Data Mode 2
No Depth Curve

1. Check mark the Select check box.

2. Indicate the two CAD edges that are normal to each other.

3. Deselect the check box.

4. Click on the part.

If a depth curve is not selected PC-DMIS simply drops the selected point onto the curve.

Note: Only LINEAROPEN, LINEARCLOSE and PATCH scans can use wire frame data.